January 12, 2026
Notable earthquakes and events:
The geomagnetic storm which began late on January 10, 2026 (see previous issue for a summary)
continued today on January 11. A period of time from 18:00 to 22:00 UT was the
most intense with high latitude Kp reaching 6 for nine hour and Planetary
KP reaching 5.3 around 21:00 UT. Middle latitude Kps also were elevated, with the
daily Kp of 20. The last time the middle latitude Kp exceeded 20 was on December 4, 2025 with Kp 24.
Earthquakes of M 5.1 and M 5.6 in the Kuril Islands occurred during the height
of this geomagnetic storm and may have been triggered by it.
The strongest earthquake of the day was an M 5.6 in the southern Kuril Islands.
NEIC reported it was probably felt with intensity up to II in the area of Kuril'sk, Russia.
This event occurred within minutes of local solar noon and was probably
promoted by tidal and/or geomagnetic stresses which maximize near this hour.
It is consistent with the regional forecast for this area made in an earlier
issue of this forecast for this time which read:
"In the past several issues, this summary has followed the continuing activity
in Northern Japan with interest. This is a continuing series which began
on November 9, 2025 (M 6.8) with ensuing events on December 8, 2025 (M 7.6)
and December 31, 2025 (M 6.0). A further strong earthquake in this series is possible
but unlikely (unless a major unexpected solar flare occurs) around January 6-8, 2026 in the northern Honshu to Hokkaido area.
These events have been associated with major solar flares of high M-class to X-class and appear to be related to a sunspot
group rotating with the sun. If this continues a second time for another such event
would be around January 23-27, 2026. This would be most likely to the northeast
of the current series in the Southern Kuril Islands. ..." (January 4, 2026)
This earthquake in the Kuril Islands also occurred during a strong M3.3 class
solar flare. This flare occurred on the solar rim and had a major Coronal
Mass Emission associated with it. The sunspot region will continue
to rotate reaching an area directly in the center of the sun as seen from
earth around January 20-21. A major flare at that time from this sunspot
group could trigger additional seismicity. This will occur with the new
moon of January 18 (UT) which will see areas of coastal California at
local solar noon at its completion. The combination could promote a moderate
to strong earthquake in the currently active region near San Ramon, California.
This summary will keep readers advised on this possibility. SWPC data for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9370 2153 2314 0031 M3.3 (January 11, 2026) 2.1E-01
9370 2153 2314 0200 M3.3 (January 11, 2026) 2.1E-01 *
Southern Peru M 4.2 21:51 UT
San Francisco M 2.5 21:44 UT
Ryukyu Is. M 4.7 23:50 UT
Banda Sea M 4.3 23:53 UT
Baja California M 4.0 23:54 UT
Fox Is. M 4.1 00:06 UT
Hokkaido M 4.8 00:50 UT M 4.1 00:48 UT M 4.3 00:58 UT
Argentina M 4.4 00:57 UT
*indicates modified reading from NOAA GOES Graph
The M 5.6 epicenter in the Kuril Islands today is located at the fourth node (90 degrees)
from TC Dudzai and at the eighth node (45 degrees) from Mindanao and may have
been promoted by energy from those sources.
O: 12JAN2026 01:52:57 47.7N 147.4E MW=5.6 EMSC NORTHWEST OF KURIL ISLANDS
The earthquake of M 5.6 in the Kuril Islands was not alone among moderate earthquakes
today in the area from Hokkaido, Japan to Kamchatka. A series of such events
occurred with the flare and geomagnetic storm which coincided.
Other events occurred in northern Honshu, Japan (M 4.1); the southern Kurils
(M 4.7, 4.4); Hokkaido, Japan (M 4.8, 4.1, 4.3); northwest of the Kuril Islands (M 5.6);
the northern Kurils (M 4.9, 5.1, 4.2, 4.9 and 4.4); Kamchatka (M 4.9, 4.2, 4.6, 4.5, 5.0)
and in northern Kamchatka M 4.9, 4.4). These events show that the entire
subduction zone from northern Honshu through Kamchatka was activated
simultaneously - probably by the combination flare and geomagnetic storm.
That this happened piecemeal with approximiately 200 km between each
outburst without a corresponding strong to major
event is highly unusual and suggests that the locked segments between those
activated today are tightly locked may prevent a mega-thrust earthquake from happening
soon.
O: 12JAN2026 03:14:30 38.3N 141.8E ML=4.1 EMSC NEAR EAST COAST OF HONSHU,
O: 11JAN2026 17:35:56 43.3N 147.9E MB=4.7 EMSC KURIL ISLANDS
O: 11JAN2026 17:14:42 43.5N 147.1E mb=4.4 EMSC KURIL ISLANDS
O: 12JAN2026 00:50:16 45.1N 142.2E MB=4.8 EMSC HOKKAIDO, JAPAN REGION
O: 12JAN2026 00:48:30 45.0N 142.2E ML=4.1 EMSC HOKKAIDO, JAPAN REGION
O: 12JAN2026 00:58:30 45.0N 142.2E ML=4.3 EMSC HOKKAIDO, JAPAN REGION
O: 12JAN2026 01:52:57 47.7N 147.4E MW=5.6 EMSC NORTHWEST OF KURIL ISLANDS
O: 11JAN2026 07:29:50 49.2N 156.0E MB=4.9 EMSC KURIL ISLANDS
O: 11JAN2026 19:37:55 49.3N 156.1E mb=5.1 EMSC KURIL ISLANDS
O: 12JAN2026 03:46:50 49.3N 156.2E mb=4.2 EMSC KURIL ISLANDS
O: 11JAN2026 18:27:50 49.5N 156.1E mb=4.9 EMSC KURIL ISLANDS
O: 11JAN2026 16:13:18 50.0N 156.9E mb=4.4 EMSC KURIL ISLANDS
O: 12JAN2026 05:00:42 51.9N 158.5E MB=4.9 EMSC NEAR EAST COAST OF KAMCHATKA
O: 11JAN2026 19:16:29 51.3N 159.9E mb=4.2 EMSC OFF EAST COAST OF KAMCHATKA
O: 11JAN2026 09:02:48 51.5N 160.1E mb=4.6 EMSC OFF EAST COAST OF KAMCHATKA
O: 11JAN2026 10:38:06 51.7N 159.4E mb=4.5 EMSC OFF EAST COAST OF KAMCHATKA
O: 12JAN2026 06:21:44 52.8N 159.3E MB=5.0 EMSC OFF EAST COAST OF KAMCHATKA
EMSC reported these earthquake were lightly felt in Russia at Yelizovo and Petropavlovsk-Kamchatsky.
O: 12JAN2026 05:04:07 56.0N 162.8E MB=4.9 EMSC NEAR EAST COAST OF KAMCHATKA
O: 12JAN2026 05:35:22 55.6N 162.6E mb=4.4 EMSC NEAR EAST COAST OF KAMCHATKA
Activation of seismicity was not limited to the Pacific Northwest quadrant. In the
U.S. and Mexico a series of earthquakes including an M 4.0 occurred near the
U.S./Mexico border in Baja California. These were closely associated with
the M3.3 solar flare as well as the day's geomagnetic storm and were
likely triggered by them. NEIC reported they were likely felt with intensity
up to II in the epicentral area near Maneadero, Baja California, Mexico.
These epicenters are at 60.0 degrees (node 6) from the North Geomagnetic
Pole and from Kamchatka and at 102 degrees from Taiwan and were likely
promoted by constructive interference of energy from those sources.
O: 11JAN2026 10:37:13 31.4N 115.6W ML=3.2 EMSC BAJA CALIFORNIA, MEXICO
O: 11JAN2026 22:35:41 31.4N 115.2W ML=3.0 EMSC BAJA CALIFORNIA, MEXICO
O: 11JAN2026 22:18:13 31.5N 115.7W ML=3.3 EMSC BAJA CALIFORNIA, MEXICO
O: 11JAN2026 23:54:23 31.6N 115.8W ML=3.9 EMSC BAJA CALIFORNIA, MEXICO
O: 12JAN2026 05:02:06 31.6N 115.7W ML=3.1 EMSC BAJA CALIFORNIA, MEXICO
O: 11JAN2026 08:12:51 32.8N 115.8W ML=2.7 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.1 in Central California was felt with intensity up to II-III in the area(s) of Central California with III in Caliente, Frazier Park and II in Los Angeles, Tehachapi and Bakersfield.
This epicenter is located at 104 degrees from Mindanao and may have been promoted
by energy from that source.
O: 12JAN2026 07:02:46 35.1N 119.0W ML=3.1 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.2 in eastern France near the Italy/Switzerland border occurred today. NEIC reported it was felt with intensity IV in Chamonix-Mont-Blanc, Rhone-alpes, France.
EMSC reported hard shaking in Courmayeur, Italy and in France at Les Contamines-Montjoie, La Bathie and in Troistorrents, and Les Avanchets, Switzerland.
This is the strongest earthquake within about 200 km of this French epicenter
northwest of Turin, Italy since an M 4.5 on March 12, 2022. At the time this
summary noted:
"A moderate earthquake of M 4.5 was widely felt in the French Alps today. NEIC reported maximum intensity IV in France in the Rhone-Alpes at Pallud, Cesarches, Tournon, and II-III in Faverges, Plancherine, Queige, Saint-Jorioz, La Balme-de-Thuy, Annecy and Villaz.
A lightly felt aftershock of M 3.8 also occurred about 18 minutes after the mainshock
Several light foreshocks of M 2.4 and 2.1 occurred prior to the mainshock beginning
atou three hours earlier. The last earthquake of M>=4.4 occurred as an M 4.4
on October 24, 2016, but the last of larger magnitude was an M 4.7-4.8 on April 7, 2014." (March 12, 2022)
Like the earthquake in Central California (See above) this epicenter is located
at 104 degrees from Mindanao and at the fourth node (90 degrees) from TC Dudzai and Taiwan
and may have been promoted by energy from those sources.
O: 12JAN2026 06:28:50 45.9N 6.8E ML=4.2 NEIC FRANCE
O: 12JAN2026 06:28:50 45.9N 6.8E ML=3.6 EMSC FRANCE
NEIC reported an earthquake of M 4.2 in Hindu Kush, Afghanistan was felt with intensity up to II-III in the area(s) of Hindu Kush, Afghanistan in Dushanbe, Tajikistan.
This epicenter is at the seventh node (52 degrees) from TC Dudzai and the North Geomagnetic Pole
and at the sixth node (60 degrees) from Mindanao and Kamchatka and may have
been promoted by energy from those sources.
O: 12JAN2026 03:18:16 36.5N 68.3E MB=4.2 EMSC HINDU KUSH REGION, AFGHANISTAN
NEIC reported an earthquake of M 3.2 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Chugiak.
O: 11JAN2026 23:37:21 61.7N 149.6W ML=3.2 EMSC SOUTHERN ALASKA
NEIC reported an earthquake of M 2.6 in San Francisco, California was felt with intensity up to II-III in the area(s) of San Francisco, California in Alameda, Antioch, Stockton and Brentwood.
This was likely triggered by the M3.3 solar flare today (see above).
O: 11JAN2026 21:44:25 38.0N 121.8W MD=2.5 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 4.7 in Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Mindanao, Philippines in Dumlan.
O: 11JAN2026 17:28:01 7.3N 126.3E MB=4.7 EMSC MINDANAO, PHILIPPINES
NEIC reported an earthquake of M 2.5 in Northern California was felt with intensity up to II-III in the area(s) of Northern California at Placerville.
O: 11JAN2026 17:23:11 39.5N 120.3W MD=2.5 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.8 in Western Iran was felt with intensity up to II-III in the area(s) of Western Iran with IV in Iraq at al-Haritlah, al-Basrah; III in Abu al-Hasib and in Kuwait in Hawalli.
EMSC reported it was felt with strong shaking in Iraq at Al Harithah, Al Basrah al Qadimah, Basrah, Al Madinah and in Kuwait at Kuwait City, As Salimiyah, Hawalli, Al Mahbulah, Ad Diwaniyah, Kasnazan.
This is an unusual earthquake, the largest recorded within about 150 km of
this epicenter in at least 35 year. Most such regional events occur about 150 km
to the north and east of today's epicenter. The last of these was an M 5.1 on February 16, 2025
about 150 km to the north of today's epicenter on February 16, 2025.
At the time this summary noted:
"NEIC reported an earthquake of M 5.1 in Western Iran was felt with intensity up to IV in the area(s) of Western Iran at Ahwaz Khuzestan; II in Araq Markazi and possible in Kuwait.
EMSC reported moderate shaking in Iran at Dorud County, Ilam, Esfahan.
A foreshock of M 4.4 was reported lightly felt in Iran in Dorud County and in Hamadan." (February 16, 2025)
The last earthquake of significantly larger magnitude in western Iran occurred
on December 5, 2024 with M 5.6 and was noted in this summary as:
The strongest earthquake in the world today was an M 5.6 in Khuzestan, Iran. NEIC reported it was felt with intensity V at Masjed Soleyman and Khurramabad, Lorestan withi IV felt in Ahwaz, Bandar-e Mah Shahr, Desful, Shushter, Khuzestan. It was also felt with intensity III in Kuwait at Salmiya, Abu Hulayfah, al-Manqaf, and Subhan Mubarak.
NEIC reported an aftershock of M 5.0 in Iran was felt with intensity up to II in the area(s) of Iran at Ahwaz, Khuzestan.
The mainshock was followed by aftershocks of M 4.9 and 5.0 - both of which were
felt in the same epicentral area. The last earthquake of M>=5.6 within about
250 km of today's epicenter was an M 5.7 on July 8, 2019. At the time this
summary noted:
"The second largest earthquake of the day was an M 5.7 in Western Iran. NEIC reported maximum intensity VII in Iran at Khuzestan and lesser shaking within abotu 200 km of the epicenter,
It was accompanied by several moderate aftershocks. The last earthquake within about
250 km of this epicenter with M>=5.7 was an M 6.2 and aftershocks on August 18, 2014." (July 8, 2019)
Today's unusual epicenter located at the sixth node (60 degrees) from
the North Geomagnetic Pole; the fourth node (90 degrees) from Yukon, Canada
and the fifth node (72 degrees) from Honshu, Japan and may have been promoted
by energy from those sources.
O: 11JAN2026 17:02:39 31.0N 48.1E MB=4.9 EMSC WESTERN IRAN
EMSC reported an earthquake of M 4.9 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar in Idia at Imphal, Dimapur, Bokajan, Lumding Railway Colony, Sibsagar, Tezpur,Naharlagun, Tinsukia, amd Guwahati.
O: 11JAN2026 20:15:40 24.8N 95.1E MB=4.5 EMSC MYANMAR
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE DUDZAI (14S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC DUDZAI 2026-01-12 00:00 UT 16.6S 77.8E 125 kts South Indian Ocean
Tropical cyclone Dudzai continued today as a major storm in the South Indian Ocean with winds up to 125 kts. It is expected to track to the south and turning to the west over the next several days. Regional seismic enhancement in the Indian Ridge systems is possible at this time. The antipode at 17N 103W is in Jalisco, Mexico. Seismicity. Watch for enhanced seismicity in western Mexico in the next several days. The Revillo Gigedo Island group will be antipodal to TC Dudzai around January 17. This active region could see further enhancement at that time.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 11, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9270 1409 1418 1421 C3.0 (January 11, 2026) 9.7E-04
9370 2153 2314 0031 M3.3 (January 11, 2026) 2.1E-01
Southern Peru M 4.2 21:51 UT
San Francisco M 2.5 21:44 UT
Ryukyu Is. M 4.7 23:50 UT
Banda Sea M 4.3 23:53 UT
Baja California M 4.0 23:54 UT
Fox Is. M 4.1 00:06 UT
Hokkaido M 4.8 00:50 UT M 4.1 00:48 UT M 4.3 00:58 UT
Argentina M 4.4 00:57 UT
9370 2153 2314 0200 M3.3 (January 11, 2026) 2.1E-01 *
Kuril Is. M 5.6 01:53 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: Major storms January 12 active January 13-14, 2026. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies: global: 31, high: 46, mid-latitude: 20, time of max AP: 18:00 to 22:00 UT; Max AP: 6; Sunspot Number: 84; Radio Flux: 111
The geomagnetic storm which began late on January 10, 2026 (see previous issue for a summary)
continued today on January 11. A period of time from 18:00 to 22:00 UT was the
most intense with high latitude Kp reaching 6 for nine hour and Planetary
KP reaching 5.3 around 21:00 UT. Middle latitude Kps also were elevated, with the
daily Kp of 20. The last time the middle latitude Kp exceeded 20 was on December 4, 2025 with Kp 24.
Earthquakes of M 5.1 and M 5.6 in the Kuril Islands occurred during the height
of this geomagnetic storm and may have been triggered by it.
A strong Gamma Ray Burst was recorded by SWIFT on January 4, 2026 at 05:37:02 UT (#260104A). A preliminary UVOT Magnitude was not assigned to this GRB by SWIFT.
A strong Gamma Ray Burst was recorded by SWIFT on January 1, 2026 at 00:56:30 UT (#260101A). A preliminary UVOT Magnitude of V>16.17 was assigned to this GRB by SWIFT.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 11, 2026
Notable earthquakes and events:
A geomagnetic storm began on January 10 around 14:00 UT when electron flux started
a steep increase. The A-index for the day of 32 is the highest A-value
since December 3, 2025 when it also reached 32-33. The storm reached Kp at
high latitudes of 6 around 15:00 and Planetary KP of 6.0 between 1800 and 2100 UT.
GOES magnetometers show a near doubling of field strenght at the start o
the major storm at about 20:00-20:15 UT. Longitudes most likely to
see a seismic increase are at local solar noon and include areas near
120 West, including much of California. This appears to be the strongest geomagnetic storm since planetary Kp
reached 6.6 on December 3, 2025. Sudden commencement storms such as this
can trigger immediate enhanced seismicity near the geomagnetic equator
and at high latitudes and such an event, especially in Indonesia which was
at local solar midnight when this storm initiated seems likely in the
current circumstances. Additional seismic enhancement is possible in
South America and the Caribbean with this storm.
Earthquakes in the San Ramon series in northern California east of San Francisco
showed a surge late on January 10 and early on January 11 (UT) with the
geomagnetic storm (see above). These included earthquakes up to M 3.0 which
NEIC reported were felt with intensity IV in Danville and San Ramon, California and III in Dublin with II in Livermore, Alamo, Menlo Park, Union City, Pleasanton, San Francisco.
EMSC reported moderate shaking in San Ramon, Blackhawk, Dublin.
These epicenters are located at 102 degrees from Mindanao, Philippines and
at the fifth node (72 degrees) from Hokkaido, Japan and may have been
promoted by energy from those sources.
O: 11JAN2026 04:10:25 37.8N 122.0W ML=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 11JAN2026 04:21:07 37.8N 121.9W MD=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 11JAN2026 06:01:59 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 11JAN2026 06:43:52 37.8N 121.9W MD=2.4 EMSC SAN FRANCISCO BAY AREA, CALIF.
The strongest earthquake of the day was an M 6.4 in the Talaud Islands of Indonesia.
NEIC reported it was felt with intensity IV in Mindanao at Silway with III in Davao, and II in Buayan, Barra, Kinamayan, and IV in Manado, Sulawesi, Indonesia.
BMG (the local Indonesian network) reported this earthquake with M 7.1 was felt with maximum intensity VI in the Talaud Islands at Kararuan, Damau, Lirung, Melonguane, Salibabu, Kalonga, Pulutan, Moronge, Beo, Rainis, Essang, Gemeh. Lesser shaking was reported with intensity III in Kab. Sangihe, Siau, Halmahera, Morotai and II in Minahasa, Manado, Bitung, Ternate.
PHIVOLCS reported it with M 6.4 was felt in the Philippines with intensity II in Glan, Sarangani; Tupi, South Cotabato and lightly in Don Marcelino, Jose Abad Santos, and Sarangani, Davao Occidental; Bagumbayan, Sultan Kudarar; Cith of General Santos; Alabel, Malapatan, Maitum, Sarangani and Lake Sebu, South Cotabato.
This the strongest earthquake near the Talaud Islands within about 200
km of today's epicenter since an M 6.6 on April 9, 2024. At the time this
summary noted:
"The strongest earthquake in the world today was an M 6.6 in Talaud, Indonesia. NEIC reported it was felt with intensity up to IV in Tobelo, Indonesia.
PHIVOLCS reported this earthquake of M 6.5 in Talaud, Indonesia was felt with intensity up to II in the area(s) of Saranagani, City of Davao at Malungon and Glan.
BMG reported intensity IV in Ibu, Halmahera, Barat, Maluu; III in Kat Sangihe, Talaud, Siau, Halmeahera, Pulau Morotai, Tidore and Ternate among others,
This is the strongest earthquake in the Molucca Sea and Talaud within about
200 km of this epicenter since an M 7.0 on January 18, 2023 and may be
an aftershock of that event. At the time this summary noted:
"The strongest earthquake in the world today was an M 7.0-7.2 in the Molucca Sea, Indonesia. NEIC reported it was felt with intensity II in Mandao, Sulawesi and in Southern Mindanao, Philippines in General Santos City, Panabo, San Jose, Carpenter Hill, Rotonda and Davao.
PHIVOLCS reported it was felt with intensity II in Mindanao at Glan, Maaim and Malungon, Sarangani; Banga, City of Koronadal, Polomolok, Tampakan and Tupi, South Cotabato, City of General Santos, Kalamansig, Palimbang, and President Qirino, Sultan Kudarat and with
intensity I in Lake Sebu and Surallah, South Cotabato, Columbio, Sultan Kudarat.
While BMG did not expect a tsunami with this earthquake, PTWC suggested a minor tsunami is possible with this earthquake and tsunami warnings were made by BMG.
In Manado the capital of North Sulawesi and in Melonguane the quake was felt strongly and forced
many people to run from buildings. Residents reported feeling disoriented and dizzy in the area
of Gorontalo and that it lasted a long time. The earthquake was also felt in the Maluku Islands.
No major damage has been reported at this time. This earthquake occurred
at the end of a C3.0 class solar flare (see flare listing below) near local solar noon and may have
been promoted by tidal and/or SFE.
...
The last strong earthquake in the Molucca Sea occurred with M 6.3 on July 10, 2021." (January 18, 2023, April 9, 2024)
Today's earthquake occurred near local solar midnight as the strong geomagnetic
storm (see above) was beginning its sudden commencement. This was activity
which was considered possible with this storm as reported in the previous
issue of this summary:
"A geomagnetic storm began on January 10 around 13:00 UT and reached Kp at
high latitudes of 6 around 15:00 and Planetary KP of 4.33 about the same
time. This appears to be the strongest geomagnetic storm since planetary Kp
reached 5.0 on December 21, 2025. Sudden commencement storms such as this
can trigger immediate enhanced seismicity near the geomagnetic equator
and at high latitudes and such an event, especially in Indonesia which was
at local solar midnight when this storm initiated seems likely in the
current circumstances." (January 9-10, 2026)
These epicenters are at the fourth node (90 degrees) from Yukon, Canada and
at the seventh node (52 degrees) from TC Dudzai and may have been promoted
by energy from those sources.
O: 10JAN2026 14:58:23 3.7N 127.0W ML=6.4 NEIC TALAUD ISLANDS, INDONESIA
O: 10JAN2026 14:58:25 3.6N 127.0W ML=7.1 BMG TALAUD ISLANDS, INDONESIA
O: 10JAN2026 14:58:21 3.4N 127.0W ML=6.4 PHIV EAST OF BALUT ISLAND, PHILIPPINES
O: 10JAN2026 14:58:26 3.7N 127.0E MW=6.5 EMSC KEPULAUAN TALAUD, INDONESIA
O: 10JAN2026 15:15:15 3.7N 127.0E mb=5.2 EMSC KEPULAUAN TALAUD, INDONESIA
O: 10JAN2026 19:40:52 3.7N 127.1E ML=4.0 EMSC KEPULAUAN TALAUD, INDONESIA
An earthquake of M 3.8 shook Azerbaijan three minutes before the Talaud earthquake.
This is not enough time for seismic wave interaction but both may have
been triggered by the start of today's geomagnetic storm.
This epicenter is located at the sixth node (60 degrees) from TC Dudzai and from
Taiwan and may have been promoted by energy from those sources.
O: 10JAN2026 14:55:50 40.7N 48.6E MB=3.8 EMSC AZERBAIJAN
NEIC reported an earthquake of M 5.2 in northeastern Honshu, Japan was felt with intensity up to II-III in the area(s) of northeastern Honshu, Japan in Yamoto, Miyagi and Hamamatsu, Shizuoka.
This epicenter is at the sevent node (51 degrees) from Yukon, Canada
and at 103 degrees from the South Geomagnetic pole and may have been
promoted by energy from those sources.
O: 11JAN2026 04:15:37 39.6N 141.7E MB=5.2 EMSC EASTERN HONSHU, JAPAN
NEIC reported an earthquake of M 4.1 off the west coast of Lebanon was felt with intensity up to II-III in the area(s) of Lebanon with III in Jabal Lubnan at B'abda, Juniyah and Beirut.
EMSC reported strong shaking in Lebanon at Ra's Bayrut, Beirut, Baabda. Jdaidet el Matn, Sidon, Jounieh among others.
This earthquake occurred within minutes of local solar midnight and was likely
promoted by tidal and/or geomagnetic stresses which maximize near this hour.
This epicenter is located near the sixth node (60 degrees) from the North
Geomagnetic Pole and from TC Dudzai and may have been promoted by constructive
interference of energy from those sources.
O: 10JAN2026 21:50:20 34.0N 34.8E MC=3.4 EMSC CYPRUS REGION
NEIC reported an earthquake of M 4.3 in Northern Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Northern Mindanao, Philippines in Sapao, Caraga.
EMSC reported light shaking in General Luna and Siargao.
This epicenter is located near the seventh node (52 degrees) from Kamchatka
and from TC Dudzai and may have been promoted by constructive
interference of energy from those sources.
O: 10JAN2026 14:29:18 10.1N 126.0E MB=4.4 EMSC LEYTE, PHILIPPINES
NEIC reported an earthquake of M 2.7 in Southern California was felt with intensity up to II-III in the area(s) of Southern California at Hemet, Idyllwild, Menifee, Winchester, Palm Springs, Beaumont.
O: 10JAN2026 12:48:41 33.7N 116.8W ML=2.7 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 2.6 in Southern Idaho was felt with intensity up to II-III in the area(s) of Southern Idaho at Lowman.
O: 10JAN2026 11:31:23 44.4N 115.0W ML=2.6 EMSC SOUTHERN IDAHO
NEIC reported an earthquake of M 2.7 in Northern California was felt with intensity up to II-III in the area(s) of Northern California at Redding.
O: 10JAN2026 11:08:44 40.8N 122.5W MD=2.6 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.4 south of Bali, Indonesia was felt with intensity up to II-III in the area(s) of south of Bali, Indonesia with III in Kuta and Denpasar.
EMSC reported a quick tremor in Bali at Pecatu, Kangin, Jimbaran, Bualu, Kelanabian, Nusa Dua, Jabajero, Kuta, Legian, Banjar Gunungpande, Denpasar, Banjar Medura, Banjar Kertajiwa, Klumbu, Banjar Pegeringsingan, and Banjar Kedisan.
O: 10JAN2026 09:34:05 9.2S 114.7E MB=4.4 EMSC SOUTH OF BALI, INDONESIA
NEIC reported an earthquake of M 2.8 in the Texas Panhandle was felt with intensity up to II-III in the area(s) of the Texas Panhandle at Amarillo and Clerendon.
O: 10JAN2026 08:33:59 35.3N 101.7W ML=2.8 EMSC TEXAS PANHANDLE REGION
NEIC reported an earthquake of M 5.5 in Kamchatka was felt with intensity up to II-III in the area(s) of Kamchatka in Petropavlovsk,- Kamchatsky with intensity up to IV.
O: 10JAN2026 14:38:06 52.9N 160.7E MB=5.1 EMSC OFF EAST COAST OF KAMCHATKA
O: 10JAN2026 15:34:09 51.6N 158.6E mb=5.1 EMSC NEAR EAST COAST OF KAMCHATKA
O: 10JAN2026 11:31:09 52.8N 160.9E Mw=5.3 EMSC OFF EAST COAST OF KAMCHATKA
O: 10JAN2026 07:57:46 52.9N 160.9E Mw=5.5 EMSC OFF EAST COAST OF KAMCHATKA
EMSC reported an earthquake of M 4.1 in Southern Peru was felt with intensity up to IV in the area(s) of Southern Peru in Mollendo, Ciudad Satelite, Arequipa.
O: 10JAN2026 19:44:27 17.1S 72.0W ML=4.0 EMSC NEAR COAST OF SOUTHERN PERU
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE KOJI (13P)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC KOJI 2026-01-11 00:00 UT 20.1S 147.7E 45 kts North of Eastern Australia
Tropical cyclone Koji (13P) continued north of eastern Australia today. This system is currently located at 20S 148E with winds up to 45 kts. It is expected to track to the south today and to make landfall in Australia on January 11, 2026. The antipode is at 20N 32W off North Africa in the Atlantic Ocean and is not a seismic region.
TROPICAL CYCLONE DUDZAI (14S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC DUDZAI 2026-01-11 00:00 UT 15.0S 77.0E 70 kts South Indian Ocean
Tropical cyclone Dudzai formed today in the South Indian Ocean with winds up to 70 kts. It is expected to track to the southeast over the next several days. Regional seismic enhancement in the Indian Ridge systems is possible at this time. The antipode at 15N 103W is south of Jalisco, Mexico. Seismicity on the East Pacific Rise in this area has been known to be affected by Indian Ocean Cyclones. Watch for enhanced seismicity and western Mexico in the next several days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 10, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8960 0804 0814 0817 C1.1 (January 10, 2025) 5.6E-04
Kuril Is. M 5.0 08:05 UT
Kamchatka M 5.5 07:58 UT
Greece M 3.9 08:15 UT
9050 1753 1807 1816 C1.0 (January 10, 2025) 1.2E-03
Jan Mayen M 4.5 18:00 UT
Gulf of California M 4.4 18:25 UT
9070 1848 1854 1857 C1.1 (January 10, 2025) 5.1E-04
9100 1931 1942 2000 C2.1 (January 10, 2025) 2.5E-03
Southern Peru M 4.0 19:44 UT
Talaud M 4.0 19:40 UT
9110 2001 2014 2024 C3.8 (January 10, 2025) 3.8E-03
9130 2208 2232 2252 C2.0 (January 10, 2025) 4.6E-03
Western Texas M 2.5 22:08 UT
Guerrero M 4.1 22:19 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: Minor storms January 11 active January 12-13, 2026. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies: global: 32, high: 40, mid-latitude: 15, time of max AP: 18:00 UT; Max AP: 6; Sunspot Number: 65; Radio Flux: 114
A geomagnetic storm began on January 10 around 14:00 UT when electron flux started
a steep increase. The A-index for the day of 32 is the highest A-value
since December 3, 2025 when it also reached 32-33. The storm reached Kp at
high latitudes of 6 around 15:00 and Planetary KP of 6.0 between 1800 and 2100 UT.
GOES magnetometers show a near doubling of field strenght at the start o
the major storm at about 20:00-20:15 UT. Longitudes most likely to
see a seismic increase are at local solar noon and include areas near
120 West, including much of California. This appears to be the strongest geomagnetic storm since planetary Kp
reached 6.6 on December 3, 2025. Sudden commencement storms such as this
can trigger immediate enhanced seismicity near the geomagnetic equator
and at high latitudes and such an event, especially in Indonesia which was
at local solar midnight when this storm initiated seems likely in the
current circumstances. Additional seismic enhancement is possible in
South America and the Caribbean with this storm.
A strong Gamma Ray Burst was recorded by SWIFT on January 4, 2026 at 05:37:02 UT (#260104A). A preliminary UVOT Magnitude was not assigned to this GRB by SWIFT.
A strong Gamma Ray Burst was recorded by SWIFT on January 1, 2026 at 00:56:30 UT (#260101A). A preliminary UVOT Magnitude of V>16.17 was assigned to this GRB by SWIFT.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 10, 2026
Notable earthquakes and events:
A geomagnetic storm began on January 10 around 13:00 UT and reached Kp at
high latitudes of 6 around 15:00 and Planetary KP of 4.33 about the same
time. This appears to be the strongest geomagnetic storm since planetary Kp
reached 5.0 on December 21, 2025. Sudden commencement storms such as this
can trigger immediate enhanced seismicity near the geomagnetic equator
and at high latitudes and such an event, especially in Indonesia which was
at local solar midnight when this storm initiated seems likely in the
current circumstances.
NEIC reported an earthquake of M 5.5 in Kamchatka was felt with intensity up to II-III in the area(s) of Kamchatka in Petropavlovsk,- Kamchatsky with intensity up to IV.
This epicenter is at the fourth node (90 degrees) from TC Jenna and at
the seventh node from Mindanao, Philippines and may have been promoted by
energy from those sources.
O: 10JAN2026 07:57:45 52.8N 161.0E MB=5.5 EMSC KAMCHATKA
NEIC reported an earthquake of M 5.1 in the Ionian Sea, Italy was felt with intensity up to II-III in the area(s) of the Ionian Sea, Italy in Sicily, Italy at Syracuse, Catania, Montagnareale, Francavilla di Sicilia and in Malta at Sliema, Qrendi, Dingli, San Giljan, Melliena and Msida.
EMSC reported it was felt with moderate to strong intensity in Italy at Ferruzzano, Locri, Pellaro, Terreti, Reggio Calabria, Bagnara Calabra, Sambatello, Villa San Giovanni, Faro Superiore, Messina, Taormina, Rombiolo, Gaggi, Vibo Valentia, Giardini Naxos, Barcellona Pozzo di Gotto and others and in Malta at Sliema, Swieqi, San Giljan Sprachcaffe, Marsaskala among others.
The last earthquake within about 200 km of this epicenter with M>=5.1 occurred
on December 17, 2009 at a depth of 257 km and was lightly felt on the surface.
Today's M 5.1 is the strongest shallow focus earthquake in this area
in at least 35 years.
This epicenter is at 102 degrees from Mindanao, Philippines; the fourth node (90 degrees)
from Hokkaido and TC Jenna and may have been promoted by energy from those sources.
O: 10JAN2026 04:53:12 37.9N 16.3E MB=5.1 EMSC IONIAN SEA, ITALY
Sixteen seconds later an M 4.6 occurred in Greece. EMSC reported it was felt with moderate intensity
in Greece at Lamia, Kainouryion, Amfissa, Karditsa, Volos, Mitropoli, Nafpaktos, Agrino, Patra.
The simultaneity of the event with the earthquake in the Ionian Sea could not
have been produced by seismic waves, as they did not have time to travel
this distance. That leaves possible external stresses triggering both
or coincidence.
O: 10JAN2026 04:53:28 39.0N 22.4E ML=4.6 EMSC GREECE
NEIC reported an earthquake of M 5.5 in Maurtius-Reunion region was felt with intensity up to II-III in the area(s) of Mauritius-Reunion region with light intensity.
This is the strongest earthquake within about 200 km of this epicenter since
an M 5.6 on January 5, 2013. At the time this summary noted:
"The earthquake of M 5.1-5.2 in the Reunion and Mauritius region of the South
Indian Ocean was the largest event in the world today outside of southeastern
Alaska. Moderate activity in the region has been confined over the past five years to
to an epicenter about 300 km to the northeast of today's event. The earthquake
today is the strongest within 200 km of this epicenter ioccurred four years
ago on December 2, 2009 with M 5.3. The last of significantly larger magnitude
was an M 6.5 on April 16, 2006. Like the earthquake in Hawaii it is likely
that this event may have been immediately triggered by movement of magma
into cracks and crevasses in the volcanic region of La Reunion by passing
waves from the great Alaskan earthquake. The Reunion epicenter is located
at 142-144 degrees from the Alaskan and Queen Charlotte Islands epicenters.
After reflecting and refracting off core boundaries seismic waves are concentrated
on the surface in this distance zone from strong earthquakes. This concentration
of energy has been considered a possible triggering agent as seismicity in this
distance zone often increases following major earthquakes. A second such
distance range is around 103 degrees from major shocks. Earthquakes of M 4.1
in Flores, Indonesia and Chile of M 4.9 occurred in this distance range from
Alaska today. It is also likely stresses
resulting in this earthquake were acquired from the passage of a
strong tropical cyclone through the area over the past several days. This
is emphasized by a second earthquake on the path about 500 km to the north
of Reunion of M 4.8 today. In our summary yesterday it was emphasized that
this storm - Dumile - could trigger seismicity in the area at this time. That
summary stated:
"TC Dumile (07-S) continued today east of Madagascar in the South Indian Ocean with winds up to 85 kts. It is
expected to travel along the east coast of Madagascar over the next week. There is some
chance for seismicity in the La Reunion area as the eye of this storm will
pass over this island today (January 3-4, 2013) or along Madagascar over the
course of this storm. A volcanic episode at La Reunion could occur in association
with this storm." (January 4-5, 2013)
This appears to be a continuation of seismicity related to Tropical Cyclone
Grant which passed north of this epicenter several days ago. Previously
an M 5.5 occurred in the Rodrigues area and was reported in this summary as:
"A moderate M 5.4 occurred today in the Rodrigues Islands, Mauritius north of Reunion in the
South Indian Ocean. NEIC reported this earthquake was felt with intensity
up to IV in the area near Port Mathurin, Mauritius.
The last earthquake of M>=5.4 within about 200 km of today's
epicenter occurred more than 35 years ago. Regional seismicity generally
occurs about 200 km east of today's epicenter and to the south. An M 5.5
about 250 km to the east of today's event occurred on June 7, 2025.
At the time this summary noted:
"An earthquake of M 5.5 also occurred today near Reunion in the South Indian Ocean. It was followed
by several moderate regional aftershocks. It was preceded by an M 4.5 foreshock
slightly to the north of the mainquake. This mainshock occurred within minutes of
local solar midnight and may have been promoted by tidal and/or geomagnetic
stresses which seismic effects are maximized near this hour. At the same time the first named Tropical
Storm of the season formed in the area south of Michoacan, Mexico (Cosme). TS Barbara was also forming in the
area near Michoacan at the time.
...
This earthquake in the South Indian Ocean may also have been promoted by a C1.3
class solar flare (#8860)...." (June 7, 2025)
Tropical Cyclone Grant passed near this epicenter in the past several days
as noted in previous issues of this summary and may have promoted this earthquake.
On January 4 this summary noted this possibility as:
"TC GRANT 2026-01-03 00:00 UT 15.0S 64.2E 45 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 45 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely as TC Grant passes to the north in the next two days. ..." (January 4-5, 2026)
In addition to promotion from TC Grant this epicenter is also at the fifth node
(72 degrees) from Taiwan and near the fourth node (90 degrees) from Hokkaido, Japan
and may have been promoted by energy from those sources.
O: 06JAN2026 10:09:26 19.1S 64.0E MW=5.4 EMSC RODRIGUES REGION, MAURITIUS " (January 6, 2026)
O: 10JAN2026 03:22:28 19.9S 66.3E MW=5.5 EMSC MAURITIUS-REUNION AREA
Unfelt earthquakes of M 5.6 also occurred today in the area of the Fiji
Islands and in northern Vanuatu. These events occurred near local solar noon
and may have been promoted by tidal and/or geomagnetic stresses.
The M 5.6 in Vanuatu is located at the fifth node from TC Jenna; at 102 degrees
from TC Grant and at the eighth node (45 degrees) from Mindanao, Philippines
and may have been promoted by energy from those sources.
O: 09JAN2026 23:19:35 13.7S 166.6E MW=5.6 EMSC VANUATU
The earthquake in the Fiji Islands is located at the fourth node (90 degrees)
from Yukon, Canada and may have been promoted by energy from that source.
O: 10JAN2026 00:06:02 26.3S 177.5W MW=5.6 EMSC SOUTH OF FIJI ISLANDS
NEIC reported earthquake of M 2.9, 2.8 and 2.6 in the San Francisco, California east Bay aea was felt with intensity up to II-III in the area(s) of the San Francisco, California east Bay area were widely felt with intensity IV in Danville and III in San Ramon, Castro Valley, Hayward, Dublin, and II in Burlingame, San Francisco and Walnut Creek.
EMSC reported light shaking in San Ramon, Hayward and Mission District, California.
These continue the current series in the eastern San Francisco Bay area which
may be precursory to a larger regional event associated with a major solar
flare near local solar noon or midnight.
O: 10JAN2026 01:54:35 38.0N 122.2W MD=2.3 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 09JAN2026 16:14:09 37.8N 121.9W ML=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 09JAN2026 16:16:41 37.8N 121.9W MD=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 09JAN2026 16:18:31 37.8N 121.9W MD=2.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 09JAN2026 17:58:04 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 09JAN2026 18:06:56 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 2.8 in east-central South Dakota was felt with intensity up to II-III in the area(s) of east-central South Dakota.
Earthquakes in this area have occasionally preceded larger global earthquakes
especially along the Western North American boundary and to a lesser extent
in the western Pacific Ring of Fire.
This epicenter is at 103 degrees from Taiwan and 146 degrees from TC Grant
and may have been promoted by energy from those sources.
O: 09JAN2026 12:35:12 44.0N 97.8W MW=2.8 EMSC SOUTH DAKOTA
EMSC reported an earthquake of M 4.6 in Central Peru was felt with intensity up to IV in the area(s) of Central Peru at El Carmen.
This epicenter is at the fourth node from Yukon, Canada; the third node from Kamchatka and 144
degrees from TC Jenna and may have been promoted by energy from those sources.
O: 09JAN2026 17:08:50 13.3S 73.3W MB=4.6 EMSC CENTRAL PERU
EMSC reported an earthquake of M 4.0 in the Dodecanese Islands was felt with intensity up to IV in the area(s) of the Dodecanes Islands at Fethiye, Dalaman, Ortaca, and Acipayam, Turkey.
O: 10JAN2026 02:55:01 36.4N 28.7E MW=4.1 EMSC DODECANESE IS.-TURKEY BORDER R
EMSC reported an earthquake of M 4.7 in Luzon, Philippines was felt with intensity up to IV in the area(s) of Luzon, Philippines with strong shaking in Santa Cruz and milder intensity in Payocpoc Sur, Baguio.
O: 09JAN2026 16:00:18 16.1N 119.8E MB=4.7 EMSC LUZON, PHILIPPINES
EMSC reported an earthquake of M 4.9 in SE Honshu, Japan was felt with intensity up to IV in the area(s) of Tokyo, Kamagaya, Komae, Toda, Nishitokyo.
This epicenter is located at the fifth node (72 degrees) from TC Jenna and the fourth
node (90 degrees) from TC Grant and may have been promoted by energy from those
sources.
O: 09JAN2026 11:07:58 35.3N 140.5E MB=4.9 EMSC NEAR EAST COAST OF HONSHU, JAP
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE KOJI (13P)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC KOJI 2026-01-10 00:00 UT 17.9S 148.0E 55 kts North of Eastern Australia
Tropical cyclone Koji (13P) formed north of eastern Australia today. This system is currently located at 17S 148E with winds up to 55 kts. It is expected to track to the west and north today. The antipode is at 17N 32W off North Africa in the Atlantic Ocean and is not a seismic region.
A tropical cyclone may be forming in the South Indian Ocean. This system is currently located at 13S 76E and moving to the south with winds up to 33 kts. Regional seismic enhancement is possible at this time. The antipode at 13N 104W is south of Jalisco, Mexico. Seismicity on the East Pacific Rise in this area has been known to be affected by Indian Ocean Cyclones. Watch for enhanced seismicity as far north as the Revillo Gigedo Islands and western Mexico in the next several days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 9, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8820 1115 1128 1134 C3.4 (January 9, 2026) 2.3E-03
Eastern Honshu, M 4.4 11:24 UT M 4.0 11:35 UT
8860 1409 1422 1434 C1.2 (January 9, 2026) 1.6E-03
8870 1729 1748 1805 C1.0 (January 9, 2026) 2.0E-03
Minahasa M 4.4 17:38 UT
San Francisco M 2.1 17:58 UT
8900 2230 2242 2300 C1.2 (January 9, 2026) 2.0E-03
Guerrero M 3.4, 3.4 22:32 UT 22:35 UT
Vanuatu M 5.6 23:19 UT
Kenai Alaska, M 3.2 22:30 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: Minor storms January 10-11 active January 12, 2026. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies: global: 12, high: 12, mid-latitude: 9, time of max AP: 02:00 UT; Max AP: 3; Sunspot Number: 80; Radio Flux: 117
A geomagnetic storm began on January 10 around 13:00 UT and reached Kp at
high latitudes of 6 around 15:00 and Planetary KP of 4.33 about the same
time. This appears to be the strongest geomagnetic storm since planetary Kp
reached 5.0 on December 21, 2025. Sudden commencement storms such as this
can trigger immediate enhanced seismicity near the geomagnetic equator
and at high latitudes and such an event, especially in Indonesia which was
at local solar midnight when this storm initiated seems likely in the
current circumstances.
A strong Gamma Ray Burst was recorded by SWIFT on January 4, 2026 at 05:37:02 UT (#260104A). A preliminary UVOT Magnitude was not assigned to this GRB by SWIFT.
A strong Gamma Ray Burst was recorded by SWIFT on January 1, 2026 at 00:56:30 UT (#260101A). A preliminary UVOT Magnitude of V>16.17 was assigned to this GRB by SWIFT.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 9, 2026
Notable earthquakes and events:
A moderate earthquake of M 5.4 occurred in North Island, New Zealand today.
NEIC reported this event with M 5.0 was felt with intensity III in New Zealand
at Wellington, Porirua, Kapiti, Nelson, Palmerston, New Plymouth, Lower Hutt, Makara-Ohariu, Richmond, Tasman, Urenui, Levin and II in Wanganui, Taupo, Patea, Ypper Hutt, Carterton, and Te Kuiti, Waikato.
The last earthquake within North Island, New Zealand within about 150 km of
this epicenter with M>=5.4 occurred on February 15, 2023 with M 5.7. At the
time this summary noted:
"The M 5.7-6.3 in the Cook Strait, New Zealand was reported by NEIC to have been felt with maximum intensity VI in Foxton, V in Porirua, Makara-Ohariu, Kapiti, Wellington with IV in Levin, Upper Hutt, Wanganui, Lower Hutt, Palmerston North among many other communities.
This earthquake may have been promoted by effects of Cyclone Gabrielle which
hit the Kermadec Islands of northern New Zealand the remainder of New
Zealand in the past several days. That storm wrecked havoc on North Island
this week. New Zealand declared a National State of Emergency today. This
is only the third time this has happened in New Zealand history. At least four
have been declared dead and 1400 missing through the effects of TC Gabrielle
which included 80-100 mph winds and 6-12 inches of rain through North Island.
Travel was difficult or impossible throughout North Island and internet and cell
phone service were out when the cyclone damaged a fiber optic cable.
No tsunami was immediately observed or expected with today's earthquake.
Today's event in New Zealand occurred at the beginning of solar Flare 9620
and may have been promoted by SFE associated with that flare. SWPC parameters
for this flare follow:
Today's earthquake in the Cook Strait is the strongest in this region south
of Wellington, New Zealand since an M 6,2 on January 20, 2014 about 150 km
east of today's epicenter. Earthquakes about 150 km to the south of this
occurred with M 6.4-6.5 in South Island on July 21 and August 16, 2013, the
only such events in the region of Cook Strait in the past 35 years." (February 15, 2023)
GeoNet reported the following parameters for this event:
O: 08JAN2026 19:29:37 39.8S 174.5E MB=5.4 GEONET Felt with moderate to strong intensity in the area of Southern North Island, New Zealand and northern South Island. 14077 reports of felt events were made of which 7426 reported weak and 5702 light intensity with 880 reports of moderate shaking and 51 with strong and 5 severe and 12 with extreme intensity came from the area.
Today's epicenter is located at the fifth node (72 degrees) from TC Jenna and
may have been promoted by energy from that source.
O: 08JAN2026 10:20:15 37.8S 176.3E MB=4.4 EMSC NORTH ISLAND OF NEW ZEALAND
P: 02JAN2026 178632 37.0S 178.0E 3.0-4.6 CABAA North Island, N.Z.
P: 07JAN2026 178632 39.0S 176.0E 3.0-4.6 ABAAA North Island, N.Z.
O: 08JAN2026 19:29:36 39.8S 174.5E MW=5.0 EMSC NORTH ISLAND OF NEW ZEALAND
O: 08JAN2026 19:29:36 39.8S 174.5E MW=5.4 GEONET NORTH ISLAND OF NEW ZEALAND
Two moderate earthquake of M 5.3 were felt widely near Tajikistan today. NEIC reported these were felt with intensity III in Os, Kyrgyzstan and II in Quva Farg'ona, Uzbekistan and in Pakistan at Baffa, Northwest Frontier and Islamabad.
EMSC reported they were felt with moderate intensity in Osh, Barken, Jalal-Abad, Kyrgyzstan; Roghun, Tajikistan, Fergana, Qo'qon, Chortoq, Uchko'prik, Uchqurghon Shahri, To'rqao'rg'on, Kirguli, Toshloq, Oltiariq, Rishton, Uzbekistan, Kashgar, China, among others.
The last earthquakes within about 150 km of these epicenters with M>=5.3 occurred
with M 5.3 on November 13, 2023 - an aftershock of an M 6.8 on February 23, 2023.
Today's activity in Tajikistan is also likely aftershocks of that event.
At the time this summary noted in this regard:
"A strong to major earthquake of M 6.8-7.2 hit the area of Tajikistan and Pakistan today. NEIC reported maximum intensity VIII with damage in Tajikistan at Murgob and II-III in Os, and Dushanbe. Intensity IV was felt in North-west Frontier, Pakistan in Mardan and Risalpur with lesser shaking in Hunza, Gilgit, Abottabad and in Uzbekistan at Quva.
While no major damage was immediately reported from this remote area, many local
residents in Badakhstan woke during the quake and rushed outside. The mainshock
was also felt wide in western Xinjiang, China including at Kashgar and Artux accorrding
to Chinese state television. CENC reported the earthquake with M 7.2 (epicenter 38.0N 73.3E).
A series of moderate aftershocks of M 4.5-5.2 followed the mainshock. There was some concern that a large lake (Sarez) could flood a vast area
spanning several countries if disturbed by this earthquake.
Internet photos showed cracked pavement and damage to buildings.
...
moon and was probably promoted by strong tidal stresses from that alignment.
Today's event in Tajikistan is the strongest within about 300 km of this
epicenter since an M 7.2 about 50 km northwest of today's epicenter on December 7, 2015 -
the only such event in the region in at least 35 years. At the time this summary noted
in this regard:
"A major earthquake of M 7.2 hit the region of Tajikistan on December 7, 2015.
It was felt widely with moderate intensity in the countries of Pakistan, Kyrgyzstan, Afghanistan, Kazakhstan, China, India, Uzbekistan and Tajikistan.
Areas reporting moderate shaking of II-IV in Tajikistan included Dushanbe and Sughd;
in Uzbekistan at Navoiy and Tashkent; in Afghanistan at Kabul, Kapisa and Nangarhar;
in India at Delhi, Haryana, Jammu and Kashmir, Punjab, Rajasthan, Uttar Pradesh;
in Xinjiang, China; Almaty, Kazakhstan; Biskek, Os, and Celalabad, Kyrgyzstan and in
Pakistan in the Federal Capital area, Northwest Frontier, and Punjab.
A series of regional aftershocks followed including an M 5.5 in Kyrgyzstan. An M 5.6
in Coquimbo, Chile a minute after the Tajikistan quake is probably coincidental
but global stresses may have helped trigger both at the same time. A major promoter of this earthquake was probably the M 7.5 in Hindu Kush of
October 26, 2015, the strongest in that region since an M 7.3 on March 3, 2002.
This epicenter is about 400 km from the current event. There have been no earthquakes
of M>=7.2 in an area within about 300 km of this epicenter in at least 25 years.
Major earthquakes within this area have occurred in the past century however.
The last was an M 7.1-7.4 on August 23, 1985. Others occurred on August 11, 1974 (M 7.3);
April 15, 1955 (M 7.2); February 18, 1911 (M 7.4-7.8) and August 22, 1902 (M 8.2).
The earthquake in 1985 was deadly and preceded the great Mexico City earthquake
of September, 1985 by less than a month. This summary's history noted on August 23
reported in regard to this event in 1985:
"At least 71 killed, 162 injured. About 85% of buildings were destroyed in the
Wuqia and Shufu area left up to 15,000 homeless. Highways were cracked nd
sandblows occurred in Wuqia County. Damage occurred at Kashi. Also felt in the USSR,
Rawalpindi, Islamabad and Peshaway, Pakistan." (August 23, 2015, December 8, 2015, February 23, 2023)
This epicenter is at the sixth node (60 degrees) from Kamchatka and TC Jenna and
at the seventh node (52 degrees) from Honshu and was probably promoted by
energy from those sources.
O: 08JAN2026 16:59:57 37.4N 74.7E MB=5.3 EMSC TAJIKISTAN
O: 08JAN2026 21:14:16 38.3N 73.3E MW=5.3 EMSC TAJIKISTAN
O: 08JAN2026 19:08:36 38.4N 73.9E mb=4.6 EMSC TAJIKISTAN
NEIC reported an earthquake of M 4.4 in Morocco was felt with intensity up to II-III in the area(s) of Morocco in Malaga, Spain in Ojen, Malaga, Fuengirola.
EMSC reported it was lightly felt in Gibraltar as well as in Spain at Fuengirola, Alhaurin de la Torre, Malaga, Torrox and in Kenitra, Morocco.
Today's event is located near the antipode of the M 5.4 in North Island, New
Zealand today (see above) and may have been associated with antipodally focused
energy from that source and an M 4.4 in North Island, New Zealand earlier in the day. This is the strongest earthquake within about 150 km of this epicenter in
the Strait of Gibraltar since an M 4.4 on December 5, 2025. At the time this summary noted:
O: 08JAN2026 10:20:15 37.8S 176.3E MB=4.4 EMSC NORTH ISLAND OF NEW ZEALAND
"NEIC reported an earthquake of M 4.4 in Strait of Gibraltar was felt with intensity up to II-III in the area(s) of Strait of Gibraltar in Malaga, Spain at Fuengirola, Torremolinos, Rincon de la Victoria.
EMSC reported moderate shaking in Spain at Fuengirola, Benalmadena, Mijas, Torremolinos, Alhaurin de la Torre, Marbella, Malaga, Casarabonela, Rincon de la Victoria, Benahavis, Torre del Mar, Benamocarra, Velez-Malaga, Vinuela, Manilava, Albarrobo among others." (December 5, 2025.
The last earthquake in this area of M>4.4 was an M 5.2 on January 7, 2023
three years ago. At that time it was reported in this summary:
"An earthquake of M 5.2 near antipode of the M 5.5 in Auckland, New Zealand of
January 3, 2023 occurred today in Morocco. NEIC reported it was felt with intensity V in Taza, Morocco. EMSC
reported moderate shaking in Morocco at Bni Bouayach, Imzouren, Al Hoceima, El Arba de Trougout, Ajdir, Driouch, En Nador, Taza, Bni Chiker and Selouane among other communities. This
is near the longitude of maximum tidal stress with today's full moon and
is consistent with tidal triggering from that tidal alignment. Today's
earthquake is the strongest in the region of the Strait of Gibraltar or Morocco
since an M 4.9 north of this on October 4, 2022 and an M 5.5 on May 20, 2022.
At the time of the October event, this summary noted:
"An unusually large M 4.9 occurred in the Strait of Gibraltar today. This area
has been active at lower magnitudes for several weeks. The only earthquake
near this epicenter in the past two years with M>=4.9 occurred on August 28, 2021 (M 5.1)
and an M 4.9 on June 2, 2022. At the time of the event in August 2021 this summary noted
in this regard:
"An earthquake of M 5.1-5.3 also occurred today in the Strait of Gibraltar. NEIC reported it was felt with maximum intensity V in Ceuta, Spain, IV in Benamccarra, Velez-Malaga and Melila, Spain and II-III in Spain at Torremolinos and Granada and in Gibraltar and in Morocco at Al Hoceima and Inzouren.
This area became active in January, 2016 with a maximum sized event of M 6.3 on
January 25, 2016. Today's M 5.3 is the strongest aftershock in the region
since an M 5.6 on March 15, 2016" (August 29, 2021, October 4, 2022, January 7, 2023)
Today's epicenter is located at 102-104 degrees from Taiwan and TC Jenna and
at the fourth node (90 degrees) from Kamchatka and may have been promoted
by energy from those sources. It is also about 200 km from the exact antipode
of an M 4.4 in North Island, New Zealand that occurred about 7 hours earlier.
O: 08JAN2026 17:32:06 35.8N 4.6W MB=4.4 EMSC STRAIT OF GIBRALTAR
O: 08JAN2026 10:20:15 37.8S 176.3E MB=4.4 EMSC NORTH ISLAND OF NEW ZEALAND
NEIC reported earthquakes of M 3.1 and M 3.1 in Louisiana were felt with intensity up to II-III in the area(s) of Louisiana with III in Coushatta,Shreveport, Mansfield, and II in Ringgold and in Natchez, Mississippi and Texarkana, Texas.
The second of these may have been promoted by SFE from solar flare 8600 (C2.7)
which began simultaneously with the earthquake and with an M 4.3 in Gansu, China. Data on this flare from
SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8600 1600 1609 1611 C2.7 (January 8, 2025) 1.2E-03
Louisiana M 3.1 16:01 UT
Gansu, China M 4.3 16:01 UT
The last earthquake in Louisiana within about 150 km of this epicenter was an
M 3.2 on August 22, 2025. At the time this summary noted:
"Unusual earthquakes of M 3.0 and M 2.6 were felt along the Texas-Louisiana border today shortly
before the M 7.5 in the Drake Passage. NEIC reported intensity III in Center, San Augustine, Shelbyville, Texas and II in Kilgore, Tyler Texas.
This is the strongest earthquake within about 100 km of this epicenter since
a series of earthquakes hit about 100 km north of this in Louisiana in December
2024 and January, 2025. At the time this summary noted:
"An earthquake of M 3.5 was widely felt today in the area of Texas and Louisiana. NEIC reported maximum
shaking of V at Allen Texas with IV in Louisiana at Mooringsport, Shreveport and Barksdale, AFB. Intensity II was felt in Bossier City, and in Texas at Karnack, Kilgore, with lesser shaking in Louisiana at Belcher, Benton, Greenwood, Bossier City an Stephens, Arkansas.
Along with a similar M 3.5 on January 27, 2024 this is the largest earthquake
in the region of Louisiana within about 100 km of today's epicenter in at least
35 years. A series of earthquakes of M 3.0 and M 3.1 began in this area on December
19, 2024 ..." (January 18, 2025, August 22, 2025)
The current series in Lousiana began with an M 3.9 and M 4.8 on May 10 and 17, 2012
after no such earthquake in the period between 1994 and 2012.
These epicenters area located at the fifth node from Kamchatka and the fourth node
from Hokkaido, Japan and may have been promoted by energy from those sources.
O: 08JAN2026 16:01:36 32.1N 93.4W ML=3.1 EMSC LOUISIANA
O: 08JAN2026 15:06:38 32.1N 93.3W ML=3.1 EMSC LOUISIANA
An earthquake of M 4.2 occurred at local solar midnight in the Geysers area
of Northern California north of San Francisco today.
This event was discussed in the previous issue of this summary in part as:
"An earthquake of M 4.2 shook regions of northern California in the Geysers area
north of San Francisco today. NEIC reported it was widely felt with intensity up to V in California at Nice;
IV in Middletown; III in Cloverdale, Geyserville, Penngrove, Kelseyville, Calistoga, Clearlake Oaks, Lakeport, Healdsburg and II in Forestville, Petaluma, Ukiah, Clearlake, Saratoga, Fairfield, Napa, Santa Rosa, Rohnert Park, Saint Helena, Cotati, and Yorkville.
This earthquake occurred within several minutes of local solar midnight and
was probably promoted by tidal stresses which maximize near this hour.
The last earthquake of M>=4.2 within about 50 km of this epicenter in the
California Geysers area occurred as an M 4.7 on January 2, 2025 more than
a year ago.
...
This epicenter is at 144 degrees from Tropical Cyclone Jenna; the seventh
node (52 degrees) from Kamchatka and 101 degrees from Mindanao, Philippines
and may have been promoted by energy from those sources." (January 8, 2026)
Triggering within minutes of local solar midnight and local solar noon often indicates high levels of regional stress
and can precede stronger regional events.
O: 08JAN2026 08:00:21 38.8N 122.9W ML=4.2 NEIC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 5.2 in Argentina was felt with intensity up to II-III in the area(s) of Argentina in San Juan, Mendoza and Cordoba.
O: 08JAN2026 14:14:57 31.3S 67.5W MB=5.2 EMSC SAN JUAN, ARGENTINA
EMSC reported an earthquake of M 4.9 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar in Mandalay, Sagaing, Pyin Oo Lwin, Meiktila and Nyaungshwe with an earthquake noise.
O: 08JAN2026 14:56:35 21.9N 96.1E ML=4.5 EMSC MYANMAR
EMSC reported an earthquake of M 3.9 in Assam, India was felt with intensity up to IV in the area(s) of Assam, India in Dispur, Guwahati, Palasbari, Nongpoh, Meghalaya, and in Pemagatshel, Bhutan.
This epicenter is located at the eighth node (45 degrees) from Hokkaido, Japand an TC Jenna
and may have been promoted by energy from those sources.
O: 08JAN2026 13:00:47 26.7N 92.3E ML=3.9 EMSC ASSAM, INDIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE JENNA (12S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC JENNA 2026-01-09 00:00 UT 18.2S 90.3E 55 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 55 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 18N 90W - an area of northern Guatemala. This area is active at this time and a moderate antipodal earthquake in this area is possible in the next three days. TC Jenna is then expected to reverse direction and track to the west reaching an area antipodal to northern Guatemala and Chiapas Mexico around January 8-9, 2026. It could help promote a moderate earthquake in that area in the next two days.
A tropical cyclone may be forming north of eastern Australia. This system is currently located at 14S 148E with winds up to 37 kts. It is expected to track to the west and north today. The antipode is at 14N 33W off North Africa in the Atlantic Ocean and is not a seismic region.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 8, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8470 0133 0139 0145 C1.2 (January 8, 2025) 8.9E-04
Central Mediterranean M 4.7 01:50 UT
8490 0215 0227 0242 C2.3 (January 8, 2025) 3.3E-03
8500 0442 0446 0448 C1.5 (January 8, 2025) 5.9E-04
Minahasa M 4.0 04:41 UT
Guyana M 4.5 05:06 UT
8510 0524 0542 0549 C4.4 (January 8, 2025) 3.9E-03
Ecuador M 5.5 05:18 UT
8540 0825 0833 0835 C1.3 (January 8, 2025) 8.0E-04
Hokkaido M 4.4 08:28 UT
8600 1600 1609 1611 C2.7 (January 8, 2025) 1.2E-03
Louisiana M 3.1 16:01 UT
Gansu, China M 4.3 16:01 UT
8630 1618 1730 1846 C5.6 (January 8, 2025) 3.5E-02
8680 1945 1956 2007 C3.4 (January 8, 2025) 4.2E-03
Aru, Indonesia M 4.1 20:03 UT
North Is. New Zealand, M 5.0 19:30 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms January 9 active January 10 unsettled January 11, 2026. Solar M-flare chance: 45% X-class: 10% proton storm: 10%
AP Indicies: global: 14, high: 15, mid-latitude: 8, time of max AP: 10:00 UT; Max AP: 4; Sunspot Number: 96; Radio Flux: 140
A strong Gamma Ray Burst was recorded by SWIFT on January 4, 2026 at 05:37:02 UT (#260104A). A preliminary UVOT Magnitude was not assigned to this GRB by SWIFT.
A strong Gamma Ray Burst was recorded by SWIFT on January 1, 2026 at 00:56:30 UT (#260101A). A preliminary UVOT Magnitude of V>16.17 was assigned to this GRB by SWIFT.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 8, 2026
Notable earthquakes and events:
An earthquake of M 4.2 shook regions of northern California in the Geysers area
north of San Francisco today. NEIC reported it was widely felt with intensity up to V in California at Nice;
IV in Middletown; III in Cloverdale, Geyserville, Penngrove, Kelseyville, Calistoga, Clearlake Oaks, Lakeport, Healdsburg and II in Forestville, Petaluma, Ukiah, Clearlake, Saratoga, Fairfield, Napa, Santa Rosa, Rohnert Park, Saint Helena, Cotati, and Yorkville.
This earthquake occurred within several minutes of local solar midnight and
was probably promoted by tidal stresses which maximize near this hour.
The last earthquake of M>=4.2 within about 50 km of this epicenter in the
California Geysers area occurred as an M 4.7 on January 2, 2025 more than
a year ago. At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 4.7 in the Geysers
region of Northern California. Press reported the earthquake was felt as far
as San Francisco as a rolling motion. While some minor damage was reported
no significant damage was noted. More than 1500 people reported to the USGS
that they had felt this earthquake. Maximum intensity occurred as VI at Sacramento with V in California at Kelseyville, Middletown, III in San Francisco, Calistoga, Fairfield, Hercules, Saint Helena, Yountville, Oakland, San Rafael, San Anselmo, Sausalito, Santa Rosa, Clearlake, Cloverdale, Geyserville, Glenhaven, Healdsburg, Hopland, Lakeport, Lower Lake, Monte Rio, Nice, Hidden Valley Lake. It was felt lightly in areas as far as 250 km from the epicenter in Nevada, and Central California.
EMSC reported moderate shaking in northern California at Kelseyville, Middletown, Healdsburg, Petaluma, Fairfield, Vallejo, Pinole, and San Francisco.
This earthquake is near the fourth node (90 degrees) from the M 7.4 in Vanuatu
of December 17, 2024 and may be an FFA of that event. Also like many of the
larger eventss in the California Geysers area this was closely associated
with the supermoon of December 30, 2024 and with the strongest geomagnetic
storm in nearly three months, both of which probably helped promote today's
M 4.7 in northern California. The last earthquake in
the Geysers area of California within about 100 km of today's epicenter with
M>=4.7 occurred on December 14, 2016 with M 5.0. The largest earthquake in the area
and the only of M>6.0 in the past 35 years occurred as an M 6.0 near Napa on
August 24, 2014. At the time of the 2016 earthquake this summary noted:
"The strongest earthquake in California today was an M 5.0 north of San Francisco
in the Geysers area of California. NEIC reported the mainshock was felt with intensity up to VI (minor damage) with reports of intensity V from Kelseyville; IV from Geyserville, Cloverdale, Middletown, Lakeport, Lower Lake, Cazadero, Upper Lake, Mendocino, and in general within about 100 km of the epicenter. Lesser shaking was reported from as far away as 470 km at Nipomo but these reports
probably refer to the Templeton earthquake in central California. Lesser shaking
associated with the Geysers event probably was limited to areas within about
150 km of that epicenter including, but not limited to San Mateo, San Rafael, Vacaville, Fairfield, Napa, Sonoma, Petaluma, Potter Valley, Yountville, Bodega Bay, Rohnert Park, Saint Helena, Santa Rosa, Ukiah, Sebastopol, Angwin, Healdsburg, Hopland, Hidden Valley Lake, Lucerne, Clearlake, Windsor, Calistoga, Guerneville, and Forestville, California.
Aftershocks were felt with intensity II-III in Lakeport, Calistoga, Sebastopol, Ukiah, Saint Helena, Cloverdale, Healdsburg, Windsor, Santa Rosa and San Francisco, California.
No major damage was reported with this earthquake. It is the strongest earthquake
in the Geysers area within about 50 km of this epicenter in at least 25 years.
Earthquakes hit the Napa area with M 6.0 on August 24, 2014 and with M 5.0 on September 3, 2000.
While smaller earthquakes in the Geysers, California are nearly continuous, events
of larger magnitude are uncommon. Today's earthquake may be the largest ever
recorded in the Geysers area, in fact. An M 5.0 was recorded on May 7, 1955 but
magnitudes were not well determined at the time. No other events in the Geysers
area have reached M>=5.0 until today." (December 14, 2016, January 2, 2025)
This epicenter is at 144 degrees from Tropical Cyclone Jenna; the seventh
node (52 degrees) from Kamchatka and 101 degrees from Mindanao, Philippines
and may have been promoted by energy from those sources.
O: 08JAN2026 08:00:21 38.8N 122.9W ML=4.2 NEIC NORTHERN CALIFORNIA
An earlier M 2.0 occurred north of San Francisco today within a few minutes
of local solar noon. This repeats a pattern which is common among light
earthquakes in this area in the past several months and could be precursory
to a stronger earthquake upcoming. EMSC reported it was felt with light
intensity in the San Francisco Bay area near Vallejo.
This epicenter is at 145 degrees from Tropical Cyclone Jenna; the fifth
node (72 degrees) from northern Honshu and 102 degrees from Mindanao, Philippines
and may have been promoted by energy from those sources.
O: 07JAN2026 20:08:17 38.1N 122.2W ML=2.0 NEIC NORTHERN CALIFORNIA
NEIC reported earthquakes of M 3.0, M 3.3 in Central California was felt with intensity up to II-III in the area(s) of Central California with III in Trona and II in Ridgecrest, Long Beach, Inyokern, Lancaster.
These followed an M 3.6 earlier in the day which was felt with intensity II in Independence,
California.
These epicenters are 105 degrees from Mindanao, Philippines and may have
been promoted by energy from that source.
O: 08JAN2026 05:28:06 35.7N 117.5W ML=3.0 NEIC CENTRAL CALIFORNIA
O: 07JAN2026 23:56:43 35.7N 117.5W ML=3.3 NEIC CENTRAL CALIFORNIA
O: 07JAN2026 23:56:43 37.3N 117.9W ML=3.6 NEIC CENTRAL CALIFORNIA
An earthquake of M 2.6 occurred today in the area of eastern Los Angeles, California.
NEIC reported it was felt with intensity II in the greater Los Angeles area
with intensity II in Palmdale, Lake Arrowhead, Cedarpines Park, Crestline, San Bernardino and Garden Grove.
This event occurred near local solar noon and may have been promoted by
tidal and/or geomagnetic stresses.
This epicenter is at the sixth node (60 degrees) from Kamchatka and may have been promoted
by energy from that source.
O: 07JAN2026 20:51:41 34.2N 117.3W ML=2.6 NEIC SOUTHERN CALIFORNIA
The strongest earthquake in the world today was an M 5.5 on the Peru-Ecuador border. NEIC reported it was felt with intensity IV in San Ignacio, Cajamarca, Peru and Yantzaza Zamora, Chinchipe, Ecuador with III in Ecuador in the Loja, Azuay, PichinchaSantiago and Chimborazo areas and in Peru in Piura and Santiago.
EMSC reported moderate shaking in Ecuador at Loja, Guayaquil, Eloy Alfaro.
This earthquake occurred within minutes of local solar midnight and may have
been promoted by tidal and/or geomagnetic stresses which maximize near this hour.
The last earthquake of M>=5.5 within about 200 km of this epicenter occurred
as an M 5.5 on October 22, 2025. The last of larger magnitude was an M 6.8 on March 18, 2023.
At the time of this event about 200 km northwest of today's epicenter this summary
noted:
"A strong M 6.7-6.8 hit the coast of Western Ecuador and northern Peru today.
NEIC reported it was felt with maximum intensity IX at Balao, Guayas, Ecuador; VIII in Naranjito; VI in Naranjal, VI in Plahyas, Guayaquil, Santa Lucia, Cuenca Azuay, V in Samborondon, Eloy Alfaro among others. Initial news reports indicate extensive but minor damage to buildings and
structures with at least eleven people killed in the quake including one in Peru. Much of the damage
and casualties occurred in Cuenca and Machala when walls collapsed. The epicenter
was near Balao about two hours from Guayaquil. It was felt in at least 13 provinces
of Ecuador. Many communities lost power and a two-story home and wharf collapsed. No tsunami was observed
nor expected.
The time of this earthquake in Ecuador was within about 12 minutes of local
solar noon at a longitude near the longitude of maximum tidal stress (see above)
with the coming new moon. It is likely this earthquake was promoted by strong tidal stresses associated
with the new moon of March 21 (2023)" (March 18, 2023)
O: 08JAN2026 05:17:50 4.2S 77.8W ML=5.5 NEIC NORTHERN PERU
An unusual M 4.5 earthquake occurred about 11 minutes before the M 5.5 in
Ecuador (see above) in the area north of Guyana and eastern Venezuela.
NEIC reported it may have been felt lightly in Mabaruma, Guyana. This earthquake
occurred, like those in northern Peru (see above) near local solar midnight
and may have been promoted by tidal stresses with the full moon of January 3, 2026. The last
event in Guyana within about 200 km of this rare epicenter with M>=4.5
was recorded as an M 5.2 and M 4.6 on January 25, 2022.
At the time this summary noted:
"An earthquake of M 5.3 was also felt in Trinidad and Tobago, Caribbean today. NEIC reported maximum intensity VI in Tabaquite and II-III in Sangre Grande and Tunapuna, Trinidad and Tobago with II in Mataruma, Guayana.
While no damage has been reported with this earthquake some light damage is
possible - perhaps from landslides. No tsunami threat exists with this earthquake.
This is the strongest earthquake within about 200 km of this epicenter since an M 5.8
on July 3, 2008." (January 2, 2022)
The surface wave from this earthquake would have arrived in Ecuador at the
time of the M 5.5 there (22 degrees and 10 minutes 50 seconds later). It may
have helped trigger that subsequent earthquake. This seems unlikely due
to the relatively small (M 4.5) magnitude of the event in Guyana but the
timing is pretty precise.
This epicenter is at 146-149 degrees from TC Jenna and from Taiwan and may
have been promoted by energy from those sources.
O: 08JAN2026 05:06:59 9.1N 59.9W ML=4.5 NEIC GUYANA
NEIC reported an earthquake of M 3.0 in Northern Utah was felt with intensity up to II-III in the area(s) of Northern Utah with II at Providence, Logan, Wellsville, Ogden, Provo, Smithfield.
This event may have been triggered by the S-wave from an M 5.5 which occurred
25.5 minutes earlier in Fiji. The S-phase would have been at the Utah epicenter
when that subsequent earthquake occurred.
O: 07JAN2026 22:25:46 41.8N 111.6W ML=3.0 NEIC NORTHERN UTAH
A moderately strong M 5.5 also occurred in the Fiji Islands with deep focus
today. It may have been felt light on the surface. This occurren near
local solar noon and may have been promoted by tidal and/or geomagnetic stresses.
This epicenter is at 60.0 degrees (node 6) from Mindanao; at the fifth node (72 degrees) from Honshu and Taiwan
and at the fourth node (90 degrees) fro Yukon, Canada and may have been promoted by energy from those sources.
O: 07JAN2026 22:00:13 23.4S 179.9W ML=5.5 NEIC SOUTH OF FIJI ISLANDS
NEIC reported an earthquake of M 4.9 in Guam was felt with intensity up to II-III in the area(s) of Guam with III in Tamuning.
O: 07JAN2026 18:02:00 14.0N 145.3E ML=4.9 NEIC GUAM
EMSC reported an earthquake of M 4.7 in the Central Mediterranean was felt with intensity up to IV in the area(s) of the Eastern Mediterranean in Chania, Greece.
O: 08JAN2026 01:50:05 35.4N 22.6E ML=4.7 EMSC CENTRAL MEDITERRANEAN SEA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE JENNA (12S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC JENNA 2026-01-08 00:00 UT 18.2S 90.3E 55 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 55 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 18N 90W - an area of northern Guatemala. This area is active at this time and a moderate antipodal earthquake in this area is possible in the next three days. TC Jenna is then expected to reverse direction and track to the west reaching an area antipodal to northern Guatemala and Chiapas Mexico around January 8-9, 2026. It could help promote a moderate earthquake in that area in the next two days.
A tropical cyclone may be forming in the North Indian Ocean. This system is currently at 6N 84E in an area of little seismicity and moving NNW with winds up to 32 kts. The antipode at 6S 96W is also not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 7, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8170 0344 0354 0357 C2.9 (January 7, 2026) 1.5E-03
Mindanao M 4.4 03:58 UT
8180 0402 0409 0412 C2.6 (January 7, 2026) 1.2E-03
Mindanao M 5.5 04:12 UT
8200 0525 0528 0533 C2.8 (January 7, 2026) 1.3E-03
8210 0606 0612 0614 C7.4 (January 7, 2026) 1.9E-03
Mindanao M 4.6 06:16 UT
8280 1121 1132 1138 C2.1 (January 7, 2026) 1.7E-03
Nevada M 2.9 11:22 UT
Northern California M 2.0 11:31 UT
8290 1208 1213 1217 C1.3 (January 7, 2026) 7.5E-04
8330 1356 1401 1408 C1.5 (January 7, 2026) 1.1E-03
8340 1412 1419 1427 C1.9 (January 7, 2026) 1.6E-03
8350 1543 1551 1602 C1.1 (January 7, 2026) 1.3E-03
Central California M 3.6 15:44 UT
8360 1614 1620 1626 C1.7 (January 7, 2026) 1.1E-03
Chiapas M 4.2 16:27 UT
8420 2152 2158 2200 C1.6 (January 7, 2026) 8.4E-04
8430 2201 2207 2212 C2.1 (January 7, 2026) 1.3E-03
Fiji M 5.5 22:00 UT
8440 2306 2314 2316 C3.2 (January 7, 2026) 1.2E-03
Northern California M 2.0 23:15 UT
Veracruz, Mexico M 4.0 23:00 UT
8460 2357 0004 0010 C1.3 (January 7, 2026) 1.0E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet January 8, minor storms January 9 active January 10, 2026. Solar M-flare chance: 45% X-class: 10% proton storm: 10%
AP Indicies: global: 5 high: 2, mid-latitude: 3, time of max AP: 22:00 UT; Max AP: 2; Sunspot Number: 118; Radio Flux: 135
A strong Gamma Ray Burst was recorded by SWIFT on January 4, 2026 at 05:37:02 UT (#260104A). A preliminary UVOT Magnitude was not assigned to this GRB by SWIFT.
A strong Gamma Ray Burst was recorded by SWIFT on January 1, 2026 at 00:56:30 UT (#260101A). A preliminary UVOT Magnitude of V>16.17 was assigned to this GRB by SWIFT.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 7, 2026
Notable earthquakes and events:
The strongest earthquake in the world today was an M 6.4 aftershock in Mindanao, Philippines.
NEIC reported it was felt with intensity up to V in Mindanao, Philippines with intensity V in Tagum, IV in Davao, Barra, Igpit, Padada, Buayan, III in Andili, Bato, Kiokong, Mawab, Bansalan, San Policarpio, Brasilisa, Caraga, and II in Balogo, Alegria, Kidapawan, Tulunan, General Luna, Baliwagan, Koronadal.
EMSC reported strong shaking in Mindanao in Mati where a witness likened the
shaking to being popcorn in a kettle. It was also felt with strong shaking
in Magugpo Poblacion, Davao, Ula, Tungao, General Santos, Klinan, Cagayan de Oro, Igpit, Tabogan.
This earthquake occurred within minutes of local solar noon and may have been
promoted by full moon tidal and/or geomagnetic effects which maximize near
this hour. The mainshock was followed by an M 5.5 aftershock about an hour later. This is the strongest earthquake in central Mindanao within about 200 km
of this epicenter since an M 7.4 on October 10, 2025 and an aftershock of M 6.7
on the same date. Distances from today's Mindanao epicenter to other earthquakes
today (and for the past three months) are included in the "DATA" section of
this summary. Today's earthquake appears to be an aftershock of those events.
At the time this summary noted:
"A major M 7.4 earthquake has occurred in Mindanao, Philippines. A tsunami alert
is currently in effect. PTWC issued a tsunami warning but only small waves
were reported and it was later withdrawn. NEIC reported the mainshock of M 7.4
was widely felt with intensity up to VIII (with damage) in Central and northern Mindanao
north to Cebu. Intensity reports published by NEIC indicated it was felt with
intensity VI in Caraga Philippines at Bayugan; V in Butuan; IV in Masarawag, Bicol, Bancasi, and III in Caraga at San Francisco, Legazpi City, Albay, Brasilisa, and II-II in Pulau at Meyungs, and Ngetkip and in Sulawesi, Indonesia.
PHIVOLCS (the local Philippines earthquake network) reported intensity V in Copostela, Maco, Mawab, Monkayo, Montevista, Nabunturan and Pantukan, Davao De Oro; Asuncion, Braulio E. Dujali, Carmen, New Corella,City of Panabo, Island Garden City of Samat, Santo Tomas and City of Tagum, Davao del Norte,
City of Davao, Jose Abad Santos, Davao Occidental; Cateel and City of Mati, Davao Oriental; City of Kidapawan, Cotabato; Alabel, Glan and Malungon, Sarangani, City of Koronadal, Tampakan and Tup, South Cotabate, City of General Santos; City of Butuan, Claver, Gigaquit and Mainit, Surigao Del Norte, In addition intensity IV was felt in the areas of the city of Tacloban, Budkidnon, Davao Del Sur, Davao Occidental, Cotabato, Sarangani, South Cotabato, Surigao del Norte and III in City of Iloilo, Eastern Samar, Leyte, Ormoc City, southern Leyte, Budidnon, City of Iligan, City of Cagayan de Oro, Davao Occidental, Cotabato, Sarangani, Sorsogon as well as throughout most of Mindanao, Leyte and Samar, Philippines.
The largest aftershocks at the time of this writing were of M 5.8-5.9. The first
of these occurred 8 minutes after the mainshock and could have been triggered
by a reflected PcP seismic wave. The second occurred within a couple
of minutes of local solar noon - as did many other significant earthquakes
around the world today and was probably promoted by strong tidal stresses
with the full moon of October 7. PHIVOLCS reported it was felt with strong intensity.
The last earthquake at shallow depth within about 200 km of this epicenter
in Mindanao, Philippines was an M 7.6 on December 2, 2023. At the time this
summary noted (in part):
The strongest earthquake in the world today was an M 7.6 in Mindanao, Philippines. NEIC reported it was felt with damage and intensity up to IX in Mindanao, Philippines.
PHIVOLCS reported it was felt with maximum intensity VII in the City of Tandag, Surigao del Sur; VI in Maco and Monkayo, Davao de Oro; Bayabas, City of Bislig and Hinatuan, Surgao del sur and V in the City of Borongan, Eastern Samar; Palo, Leyte, City of Cagayan de Oro; Nabunturan, Davao de Oro; City of Tagum, Davao del Norte; City of Davao; City of Cadadbaran, Agusan del Norte, Esperanza and Talacogon, Agusan del Sur and with lesser shaling in Bohol, City of Nandaue, Tacloban, Leyte, Budidon, Iligan, Sarangani, South Cotabato, Zamboanga, Davao, Bukidnon among others. Moderate to strong aftershocks were reported by NEIC with intensity up to V.
At least one person was confirmed killed in the earthquake with four others injured
and nine missing at initial count. More than 500 families were displaced. A tsunami warning was initially
made but was later withdrawn when no major tsunami waves were observed. Many people fled to higher ground because of the
fear of tsunami. Tsunami waves were observed in Japan with height up to 0.4 meters (1.3 feet).
Other tsunami waves were measured in the Philippines in Davao (0.3 ft); Legaspi (0.1 ft) and in Malakal Koror (Palau) east of the Philippines with 0.01 m height. A smaller event of M 6.9 hit Mindanao to the south of this two weeks ago. That event killed at least
9 and caused considerable damage to built structures, including a shopping mall ceiling
which collapsed. In today's activity there were no reports of major damage but some
roads in Surigao Del Sur were cracked by the movement associated with the
earthquakes. The mainshock occurred near local solar midnight at a location on the geomagnetic
equator as the strong geomagnetic storm was prevalent and was probably
triggered by effects associated with that storm.
Today's event of M 7.6 was the strongest in the world since an M 7.7 on May 19, 2023 in the
Loyalty Islands. Other events of M>=7.6 in the year 2023 occurred with M 7.6 in the Banda Sea on Januayr 9; in Turkey with M 7.8 on February 6 and in Tonga with M 7.6 on May 10, 2023.
The M 7.6 in Mindanao today is the strongest in the Philippines in the region
of Mindanao within about 300 km of today's epicenter since an M 7.6 on August 31, 2012, the only such event
in this area in at least 35 years. Other events of M >=7.5 hit somewhat further
to the south of today's epicenter on July 23, 2010, March 5, 2002 and January 1, 2001 (all with M 7.5).
.. " (December 2, 2023)
The M 7.4 on January 1, 2001 is the only other shallow focus epicenter within
about 200 km of this epicenter in at least 35 years.
This summary had expected this area of the central Philippines to see strong
seismic enhancement at this time. The major factor in this assessment was
that the maximum tidal stresses associated with the full (Super) harvest moon
of October 7 was at a longitude directly over this epicenter ..." (October 10, 2025)
Like this event in October, 2025 today's earthquake also occurred three days
following the full moon as previous described in this summary:
"The full moon will arrive on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026." (January 1-6, 2026)
This epicenter is at the fifth node (72 degrees) from Tropical Cyclone Grant dissipation
and at the 10th node (36 degrees) from Hokkaido and the seventh node (52 degrees)
from Kamchatka and may have been promoted by energy from those sources.
O: 07JAN2026 04:12:57 7.3N 127.0E MW=5.5 EMSC MINDANAO, PHILIPPINES
O: 06JAN2026 17:57:27 7.4N 126.8E ML=4.2 EMSC MINDANAO, PHILIPPINES
O: 07JAN2026 03:02:58 7.4N 126.8E Mw=6.4 EMSC MINDANAO, PHILIPPINES
O: 07JAN2026 04:36:44 7.4N 127.0E mb=4.9 EMSC PHILIPPINE ISLANDS REGION
O: 07JAN2026 04:46:51 7.4N 126.9E mb=4.9 EMSC MINDANAO, PHILIPPINES
O: 07JAN2026 06:16:19 7.4N 127.1E mb=4.6 EMSC PHILIPPINE ISLANDS REGION
O: 07JAN2026 03:58:22 7.2N 127.1E ML=4.4 EMSC PHILIPPINE ISLANDS REGION
The strongest earthquake in the U.S. or Canada today was an M 4.8 in the Rat
Islands, Alaska. It was not reported felt in this remote epicentral area.
It was followed by an M 4.4 regional aftershock which NEIC reported was
felt with likely intensity II in the epicentral area.
This epicenter is located at 60.0 degrees from Mindanao, the sixth node; and at
the third node from TC Grant and 101 degrees from TC Jenna and may have
been promoted by energy from those sources.
O: 06JAN2026 10:57:14 51.2N 176.9E MW=4.8 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 06JAN2026 11:14:02 51.3N 176.6E ML=4.2 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
The second strongest earthquake in the U.S. or Canada today was an M 4.5 in the Denali National Park, Alaska.
This event occurred minutes before the M 6.4 in Mindanao, Philippines.
NEIC reported it was widely felt in Alaska with III in Anchorage and Willow and II in
Talkeetna, and Chugiak. It was probably promoted by tidal stresses with the
full moon of January 3 as it lies at the longitude of maximum stress with
that alignment (see above). The last earthquake in the Denali region of Alaska
within about 200 km of today's epicenter occurred on November 27, 2025 with M 6.0.
At the time this summary noted:
"A strong earthquake of M 6.0 shook the areas near Anchorage, and Elmendorf AFB, Alaska today.
More than 7000 responses from citizens in the area to NEIC revealed it was felt
with intensity V in Alaska at Anchorage, Talkeetna, Willow, Palmer, IV in Matanuska-Susitna Borough, Chugia, Clam Gulch, Skwentana, Eagle River, Wasilla, Girdwood, Kenai, Elmendorf AFB, Fort Richarson, Indian, Cooper Landing, Kasilof, with intensity III as far as about 400 km from the epicenter.
No tsunami was expected nor observed with this earthquake. This earthquake
occurred at the peak of a high latitude geomagnetic storm with k-index of 7
and was probably promoted by that storm (see above). It is also near 100 degrees
from the earlier M 6.6 in Sumatra and the accompanying eye of Tropical Cyclone
Senyar today and at the eighth node (45 degrees) from northern Honshu, Japan today may have been promoted by energy
from those sources. This area has seen
a series of minor foreshocks in the past several days, but the last earthquake
within about 200 km of this epicenter with M>=6 occurred on November 30, 2018 with M 7.0." (November 27, 2025)
This epicenter is at the eighth node (45 degrees from Hokkaido and Honshu
Japan and may have been promoted by energy from those sources.
O: 07JAN2026 02:37:49 63.1N 150.9W MB=4.4 EMSC CENTRAL ALASKA
O: 07JAN2026 02:37:49 63.1N 150.9W MB=4.5 NEIC CENTRAL ALASKA
An earthquake of M 4.5 also occurred about 300 km southwest of today's epicenter
earlier in the day and was reported in the previous issue of this summary as:
"The strongest earthquake in the U.S. or Canada today was an M 4.5 in Southern Alaska.
NEIC reported it was widely felt with intensity II in Alaska at Anchor Point, Homer, Kasilof, Anchorage, Kenai, Ninilchik, Moose Pass, Elmendorf AFB, Sterling, Soldotna, Seward, Easgle Rive, Girdwood, Wasilla, Fort Richarson, Chugiak.
The last earthquake within about 150 km of this epicenter in Southern Alaska
was recorded by NEIC as occurring with M 4.5 on December 20, 2024." (January 6, 2026)
This epicenter is at the eighth node (45 degrees from Hokkaido and Honshu
Japan and may have been promoted by energy from those sources.
O: 06JAN2026 08:08:47 60.3N 153.7W MB=4.2 EMSC SOUTHERN ALASKA
O: 06JAN2026 08:08:47 60.3N 153.7W MB=4.5 NEIC SOUTHERN ALASKA
A moderate M 5.4 occurred today in the Rodrigues Islands, Mauritius north of Reunion in the
South Indian Ocean. NEIC reported this earthquake was felt with intensity
up to IV in the area near Port Mathurin, Mauritius.
The last earthquake of M>=5.4 within about 200 km of today's
epicenter occurred more than 35 years ago. Regional seismicity generally
occurs about 200 km east of today's epicenter and to the south. An M 5.5
about 250 km to the east of today's event occurred on June 7, 2025.
At the time this summary noted:
"An earthquake of M 5.5 also occurred today near Reunion in the South Indian Ocean. It was followed
by several moderate regional aftershocks. It was preceded by an M 4.5 foreshock
slightly to the north of the mainquake. This mainshock occurred within minutes of
local solar midnight and may have been promoted by tidal and/or geomagnetic
stresses which seismic effects are maximized near this hour. At the same time the first named Tropical
Storm of the season formed in the area south of Michoacan, Mexico (Cosme). TS Barbara was also forming in the
area near Michoacan at the time.
...
This earthquake in the South Indian Ocean may also have been promoted by a C1.3
class solar flare (#8860)...." (June 7, 2025)
Tropical Cyclone Grant passed near this epicenter in the past several days
as noted in previous issues of this summary and may have promoted this earthquake.
On January 4 this summary noted this possibility as:
"TC GRANT 2026-01-03 00:00 UT 15.0S 64.2E 45 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 45 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely as TC Grant passes to the north in the next two days. ..." (January 4-5, 2026)
In addition to promotioni from TC Grant this epicenter is also at the fifth node
(72 degrees) from Taiwan and near the fourth node (90 degrees) from Hokkaido, Japan
and may have been promoted by energy from those sources.
O: 06JAN2026 10:09:26 19.1S 64.0E MW=5.4 EMSC RODRIGUES REGION, MAURITIUS
NEIC reported an earthquake of M 3.2 in Kodiak Island, Alaska was felt with intensity up to II-III in the area(s) of Kodiak Island, Alaska at Kodiak.
This epicenter is at the third node (120 degrees) from TC Jenna and at the eighth node (45 degrees from Hokkaido and Honshu
Japan and may have been promoted by energy from those sources.
O: 07JAN2026 06:32:15 57.9N 152.2W ML=3.5 EMSC KODIAK ISLAND REGION, ALASKA
NEIC reported an earthquake of M 5.0 in Central Vanuatu was felt with intensity up to II-III in the area(s) of Central Vanuatu with II in Vila Shefa.
This epicenter was well positioned for triggering at this time. It is at 102
degrees from TC Grant; at the fifth node from Kamchatka and TC Jenna; at
the fourth node (90 degrees) from Yukon, Canada; and at the sixth node
(60 degrees) from Honshu and Taiwan and may have been promoted by energy
from those sources.
O: 06JAN2026 23:10:40 17.6S 168.2E MW=5.0 EMSC VANUATU
O: 07JAN2026 00:27:48 17.0S 168.7E mb=4.8 EMSC VANUATU
EMSC reported earthquakes of M 4.8 and M 5.2 in Kamchatka, Russia were felt with intensity up to IV in the area(s) of Kamchatka, Russia in Petropavlovsk-Kamchatsky.
These epicenters are currently located at 90 degrees (node 4) from TC Jenna
and at 52 degrees (node 7) from Mindanao and may have been promoted by energy
from those sources.
O: 06JAN2026 18:25:28 51.7N 160.3E MB=4.5 EMSC OFF EAST COAST OF KAMCHATKA
O: 06JAN2026 18:18:43 51.9N 159.8E Mw=5.2 EMSC OFF EAST COAST OF KAMCHATKA
O: 06JAN2026 07:16:36 52.6N 158.9E mb=4.8 EMSC NEAR EAST COAST OF KAMCHATKA
O: 07JAN2026 00:30:31 52.6N 159.2E mb=4.6 EMSC OFF EAST COAST OF KAMCHATKA
O: 07JAN2026 05:15:37 52.8N 160.2E mb=4.6 EMSC OFF EAST COAST OF KAMCHATKA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE JENNA (12S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC JENNA 2026-01-07 00:00 UT 17.7S 92.8E 75 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 75 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 17N 87W - an area of Honduras. This area is active at this time and a moderate antipodal earthquake in this area is possible in the next three days. TC Jenna is then expected to reverse direction and track to the west reaching an area antipodal to northern Guatemala and Chiapas Mexico around January 8-9, 2026. It could help promote a moderate earthquake in that area around that time.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 6, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7810 0010 0021 0050 C2.1 (January 6, 2026) 4.5E-03
Honshu M 5.7-6.2 01:18 UT
7860 0649 0656 0701 C1.8 (January 6, 2026) 1.3E-03
Mariana Is. M 5.2 07:01 UT
Kermadec Is. M 5.1 06:52 UT
7880 0745 0754 0800 C4.0 (January 6, 2026) 2.5E-03
Southern Alaska M 4.5 08:08 UT
7920 1151 1202 1219 C2.1 (January 6, 2026) 3.6E-03
8050 1219 1258 1325 C3.1 (January 6, 2026) 1.2E-02
Fox Is. M 3.9 12:19 UT
7930 1325 1333 1335 C2.9 (January 6, 2026) 2.3E-03
Afghanistan M 4.4 13:35 UT
7950 1543 1555 1604 C4.0 (January 6, 2026) 3.9E-03
7970 1641 1648 1650 C2.2 (January 6, 2026) 1.1E-03
8020 1951 1958 2001 C2.0 (January 6, 2026) 1.0E-03
8130 2359 0011 0014 C4.5 (January 6, 2026) 2.5E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet January 7-8, minor storms January 9, 2026. Solar M-flare chance: 40% X-class: 10% proton storm: 10%
AP Indicies: global: 4 high: 3, mid-latitude: 3, time of max AP: 10:00 UT; Max AP: 3; Sunspot Number: 99; Radio Flux: 145
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 6, 2026
Notable earthquakes and events:
A moderately strong to strong earthquake of M 5.7 (EMSC) to M 6.2 (JMA) occurred
in northern Honshu, Japan today in the western Prefectures. It occurred near
local solar noon and may have been promoted by energy from tidal and/or
geomagnetic sources. It was followed by several moderate aftershocks of M>=5 which were felt widely. NEIC reported the mainshock
was felt with minor damage in Honshu with intensity VII in Yasugi, Shimane, Sakaiminato, Tottori and VI in Matsue, Shimane, Japan.
Intensity IV was felt in Ako, Hyogo, Japan with III in Hiroshima, Kyoto, Tokushima, Osaka, Gifu, Yamaguchi and II in Fukuoka, Nara, Tokyo, and South Korea.
JMA reported intensity V-VI (Japanese intensity scale) was felt in the eastern Shimane Prefecture and
throughout much of western Honshu, Japan.
This is an unusual earthquake epicenter. The last earthquake with M>=5.7
within about 200 km of this epicenter in northern and western Honshu was
an M 6.2 on October 21, 2016 with the last of significantly larger magnitude
two events of M 6.7 on March 24, 2001 and October 6, 2000. At the time of the
event in 2016 this summary noted:
"A strong M 6.6 earthquake shook much of western Japan on October 21. NEIC reported
it was felt in Hiroshima, Nishi-ku and Gifu-shi, Japan with moderate intensity.
JMA reported many aftershocks were felt with light to moderate intensity. The mainshock
was given M 6.6 by JMA with maximum intensity VI in Tottori, V in Okayama, Shimane, Kyoto, IV in Osaka, Hyogo, Hiroshima, Kagawa. Ehime, Yamaguchi, III in Fukui, Gifu, Aichi, Shiga, Nara, Wakayama, Tokushima, Kochi, Fukuoka, Saga, Oita, Toyama, II in Ishikawa, Yamanashi, Nagano, Shizuoka, Mie, Nagasaki, Kumamoto, and I in Ibaraki, Gunma, Saitama, Chiba, Tokyo, Kanagawa, and Miyazaki Prefectures, Japan.
JMA did not recognize any threat of a tsunami with this earthquake. While there
were no immediate reports of major damage or injuries in the area, minor damage
did occur and was televised. In April two earthquakes hit the Kumamoto Prefecture
leaving widespread damage and more than 50 dead. Japan Today reported damage
included knocked over shelves and knocked out power to nearly 32,000 homes. Damage also
occurred to roof tiles, walls, and to a woman who was splashed with hot oil
while cooking during the quake. She was hospitalized.
This earthquake may have been promoted by a series of strong typhoons which
passed through the region in the past month. The most recent made landfall
over the past two days south of this epicenter in eastern China (Haima and Sarika) where strong seismic activation accompanied their landfall.
The most prominent of these recent storms was Typhoon Chaba in early to mid-October. This summary
had noted the potential for seismicity related to Typhoon Chaba as follows:
"Typhoon Chaba continued today over northern Honshu, Japan with winds up to 90 kts. It
is expected to track over northern Honshu passing north of Tokyo around September 6. It is expected to track over the center of Honshu. This will
be an atmospheric unloading event for Japan. Such events allow the upper plate
to rise with respect to the lower plate reducing normal friction across the subduction
zone. This setup can lead to a moderate to large earthquake in the subduction zone.
A seismic watch is being called for Northern and central Honshu, Japan. These areas often become active in association with
major ocean storms such as Chaba." (October 3-7, 2016)
In addition to stresses related to weather, several other factors made a
strong earthquake in Japan possible at this time. Tidal stresses probably
helped as this is not far from the longitude of maximum stress associated
with the last full moon. As Japan is particularly sensitive to geomagnetic effects, the end of the geomagnetic storm was also probably
a factor as this is about 15-20 degrees north of the geomagnetic equator,
a region in which geomagnetic triggering is most likely as noted in previous
summaries:
"Some seismicity may be triggered with this geomagnetic storm with
maximum likely strong events three to five days following the end of this geomagnetic storm (likely October 18-22) especially about 10-15 degrees
from the geomagnetic equator and at high auroral latitudes." (October 18-20, 2016, October 21, 2016)
Like the event in October, 2016 today's earthquake was also near the
full moon as previously noted in this summary:
"The full moon will arrive on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026." (January 1-5, 2026)
Likewise, a moderate C3.3 class solar flare began in concert with this earthquake.
This was the strongest solar flare reported by SWPC in the past two days. Preliminary data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0118 0150 0240 C3.3 (January 6, 2026) 4.4E-03 *
Honshu Japan M 5.7-6.2 01:18 UT
7690 0911 0920 0924 C3.0 (January 5, 2026) 2.1E-03
Honshu Japan M 3.3 09:42 UT
An M 3.3 foreshock to today's event in northwestern Honshu occurred earlier
in the day on January 5. It occurred at the end of solar flare 7690 C3.0 - the
third largest flare in the past two days. Data on this flare from SWPC
are listed above.
Enhanced seismicity was expected in northern Honshu at this time. In the January
4, 2026 issue of this summary it had been examined as:
"In the past several issues, this summary has followed the continuing activity
in Northern Japan with interest. This is a continuing series which began
on November 9, 2025 (M 6.8) with ensuing events on December 8, 2025 (M 7.6)
and December 31, 2025 (M 6.0). A further strong earthquake in this series is possible
but unlikely (unless a major unexpected solar flare occurs) around January 6-8, 2026 in the northern Honshu to Hokkaido area. ..." (January 4, 2026)
This epicenter is at the sixth node (60 degrees) from TC Jenna and from the Yukon,
Canada and may have been promoted by constructive energy interference
from those sources.
O: 06JAN2026 01:18:30 35.3N 133.2E MW=6.2 JMA WESTERN HONSHU, JAPAN
O: 06JAN2026 01:18:49 35.3N 133.1E MW=5.7 EMSC WESTERN HONSHU, JAPAN
"TC GRANT 2026-01-03 00:00 UT 15.0S 64.2E 45 kts South Indian Ocean
A moderate M 5.4 occurred today in the Rodrigues Islands, Mauritius north of Reunion in the
South Indian Ocean. NEIC reported this earthquake was felt with intensity
up to IV in the area near Port Mathurin, Mauritius.
The last earthquake of M>=5.4 within about 200 km of today's
epicenter occurred more than 35 years ago. Regional seismicity generally
occurs about 200 km east of today's epicenter and to the south. An M 5.5
about 250 km to the east of today's event occurred on June 7, 2025.
At the time this summary noted:
"An earthquake of M 5.5 also occurred today near Reunion in the South Indian Ocean. It was followed
by several moderate regional aftershocks. It was preceded by an M 4.5 foreshock
slightly to the north of the mainquake. This mainshock occurred within minutes of
local solar midnight and may have been promoted by tidal and/or geomagnetic
stresses which seismic effects are maximized near this hour. At the same time the first named Tropical
Storm of the season formed in the area south of Michoacan, Mexico (Cosme). TS Barbara was also forming in the
area near Michoacan at the time.
...
This earthquake in the South Indian Ocean may also have been promoted by a C1.3
class solar flare (#8860)...." (June 7, 2025)
Tropical Cyclone Grant passed near this epicenter in the past several days
as noted in previous issues of this summary and may have promoted this earthquake.
On January 4 this summary noted this possibility as:
"TC GRANT 2026-01-03 00:00 UT 15.0S 64.2E 45 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 45 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely as TC Grant passes to the north in the next two days. ..." (January 4-5, 2026)
In addition to promotioni from TC Grant this epicenter is also at the fifth node
(72 degrees) from Taiwan and near the fourth node (90 degrees) from Hokkaido, Japan
and may have been promoted by energy from those sources.
O: 06JAN2026 10:09:26 19.1S 64.0E MW=5.4 EMSC RODRIGUES REGION, MAURITIUS
The strongest earthquake in the U.S. or Canada today was an M 4.5 in Southern Alaska.
NEIC reported it was widely felt with intensity II in Alaska at Anchor Point, Homer, Kasilof, Anchorage, Kenai, Ninilchik, Moose Pass, Elmendorf AFB, Sterling, Soldotna, Seward, Easgle Rive, Girdwood, Wasilla, Fort Richarson, Chugiak.
The last earthquake within about 150 km of this epicenter in Southern Alaska
was recorded by NEIC as occurring with M 4.5 on December 20, 2024. At the time
this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 4.5 northwest of Anchorage, Alaska. It was felt with intensity III in Anchorage, Elmendorf AFB, Indian, Anchor Point, Chugiak, Clam Gulch, Girdwood, Homer, Kasilof, Kenai, Ninilchik, Palmer, Sterling, Juneau and II i Kenai, Cooper Landing and Eagle River among others.
This earthquake occurred at the height of a c-class solar flare and may have been
promoted by SFE associated with that flare." (December 20, 2024)
The last earthquake with signifcantly larger magnitude in this area of Alaska
occurred as an M 5.0 on July 28, 2023. At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.0 in Southern Alaska. NEIC reported it was felt with intensity II-III in southern Alaska at Levelock, Pedro Bay, Anchor Point, Kodiak, Homer, Ninilchik, Soldotna.
It was preceded by an M 4.6 in the Alaska Peninsula earlier in the day about
300 km to the south. This is the strongest earthquake within about 150 km
of this epicenter in Southern Alaska since an M 5.0 on June 18, 2023. The last
of larger magnitude in this region was an M 5.9 on December 21, 2021." (July 28, 2023)
This epicenter is at the eighth node (45 degrees) from Honshu, Japan and may
have been promoted by energy from that source.
O: 06JAN2026 08:08:49 60.3N 153.7W MW=4.5 NEIC SOUTHERN ALASKA
NEIC an earthquake of M 2.6 in Ohio was felt with intensity up to II-III in the area(s) of Ohio in Madison and Geneva with III and II in Painesville and Huntington Woods, Michigan.
The last earthquake in Ohio within about 150 km of today's epicenter with M>=2.6
occurred as an M 2.6 on June 1, 2024 with the last of larger magnitude on March 30, 2024.
At the time this summary noted:
"An unusual earthquake of M 3.0 occurred in the region of northern Ohio today. NEIC reported it was felt with intensity up to IV in Maple Ridge, Ohio.
The last earthquake in Ohio within about 200 km of this epicenter with M>=3
occurred as an M 3.6 on August 28, 2023." (March 30, 2024)
Today's earthquake occurred within minutes of local solar midnight and may have
been promoted by tidal and/or geomagnetic stresses which maximize near this
hour. It also occurred near the antipode of a strong earthquake in the South
Indian Ridge which occurred on January 3, 2026 (M 5.9) and on January 1 (M 6.0). At the time this summary noted:
"The strongest earthquake in the world today occurred as an M 5.9 in the Southeast Indian
Ridge. It was not reported felt in this remote area. This appears to be an aftershock
of an M 6.1 south of this epicenter which occurred on January 1, 2026. At the time
this summary noted in this regard:
"NEIC reported an earthquake of M 6.0 in the Southeast Indian Ridge was not felt in this
remote epicentral area. It occurred in late solar morning in this epicentral area (January 1, 2026). This is the strongest earthquake within about 300 km
of this epicenter in the Indian Ridge since an M 6.3 on March 24, 2018 and priot to that an M 6.4 on
November 10, 2010. At the time this summary noted:
"An earthquake in the South Indian Ocean of M 6.2-6.3 was also well forecast to occur
at this time. This is a remote area and this event was not reported felt. It
occurred near local solar midnight and tidal stresses may have helped promote
this event as did geomagnetic effects at this high latitude. The last earthquake
within about 200 km of this epicenter with M>=6.3 was an M 6.5 on November 10, 2010. Other quakes hit the
region with M 6.3-6.5 on October 29, 2005 and February 18, 1994. The antipode
of this event is in southern Ontario, Canada near Ohio at 45N 84W. A light
sympathetic quake could occur near this epicenter in the next several days." (March 24, 2018)
Today's epicenter in the Southeast Indian Rise is at the fifth node (72 degrees)
from Taiwan; the sixth node (60 degrees) from Mindanao and the 10th node (36 degrees)
from Tropical Cyclones Iggy and Grant in addition to 144 degrees from Yukon, Canada and may have been promoted by
energy from those sources." (January 1, 2026)
O: 03JAN2026 10:07:57 45.4S 96.5E MW=5.9 EMSC SOUTHEAST INDIAN RIDGE " (January 4, 2026)
This epicenter in Ohio is at the fourth node (90 degrees) from Honshu, Japan and the fifth node (72 degrees)
from Kamchatka and may have been promoted by energy from those sources.
O: 06JAN2026 04:50:37 41.8N 81.0W MW=2.6 NEIC OHIO
NEIC reported an earthquake of M 2.6 in northern San Francisco was felt with intensity up to II-III in the area(s) of northern San Francisco with III in San Anselmo, Vallejo and San Francisco and II in Hercules, San Rael, Lafayette, Pinole and San Pablo.
This event is not at the site of the current swarm near San Ramon and may
indicate regional stress load approaching rupture in a moderate earthquake.
The last earthquake with M>=2.6 within about 30 km of this epicenter in
San Francisco occurred as an M 3.5 on November 13, 2025. At the time this
summary noted:
"Two light earthquakes shook the region of San Francisco, California today. These events of M 3.5 and 2.5
were reported by NEIC to have been felt with intensity up to IV in the San Francisco area at Vallejo, San Anselmo,
Crockett, Benicia, and III in Pinole, Richmond, Rodeo, Hercules, Martinez, Berkeley, American Canyon, Orinda, Burlingame, Lafayette, Pleasant Hill, Walnut Creek, El Sobrante, Concord, San Ramon, Half Moon Bay, San Francisco, San Pablo, Alamo, Concord, Walnut Creek, Emeryville, among others.
These two earthquakes occurred at local solar midnight (M 2.5) and local solar
noon (M 3.5) and were probably promoted by geomagnetic and/or tidal stresses
which maximize near these hours. This continues a pattern of light earthquakes
in San Francisco over the past several weeks near local solar midnight and
Noon and could indicate the area is very close to a major rupture. Hair-triggering
in the area is especially notable at times of strong X-class flares. The X5.1
flare of November 11, 2025, the strongest in months, occurred while
San Francisco was near local solar midnight ..." (November 13, 2025)
This epicenter is at 102 degrees from Central Philippines; the fifth node (72 degrees)
from Honshu, Japan and the seventh node (52 degrees) fro Kamchatka and
may have been promoted by energy from those sources.
O: 06JAN2026 03:18:00 38.2N 122.4W MW=2.6 NEIC SAN FRANCISCO, CALIFORNIA
EMSC reported an earthquake of M 2.6 in Oklahoma was felt with intensity up to IV in the area(s) of Oklahoma in Prague.
EMSC reported an earthquake of M 4.1 in Tunisia was felt with intensity up to IV in the area(s) of Tunisia in Sejenane.
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE JENNA (12S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC JENNA 2026-01-06 00:00 UT 15.7S 94.8E 110 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 110 kts south of Sumatra exploding in size over the past day. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 16N 86W - an area of Honduras. This area is active at this time and a moderate antipodal earthquake in this area is possible in the next three days. It is then expected to reverse direction and track to the west reaching an area antipodal to Guatemala and Chiapas Mexico around January 8-9, 2026. It could help promote a moderate earthquake in that area around that time.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 5, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0118 0150 0240 C3.4 (January 6, 2026) 4.4E-03 *
Honshu Japan M 5.7-6.2 01:18 UT
7610 0109 0126 0148 C1.7 (January 5, 2026) 3.7E-03
7690 0911 0920 0924 C3.0 (January 5, 2026) 2.1E-03
Honshu Japan M 3.3 09:42 UT
7700 1012 1016 1018 C2.8 (January 5, 2026) 1.0E-03
Central Peru M 3.6 10:17 UT
7740 1237 1248 1255 C2.1 (January 5, 2026) 2.2E-03
7790 1818 1842 1906 C3.3 (January 5, 2026) 8.0E-03
Kuril Is. M 4.8 18:57 UT
7800 2032 2038 2044 C2.3 (January 5, 2026) 1.7E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet January 6-8, 2026. Solar M-flare chance: 40% X-class: 10% proton storm: 10%
AP Indicies: global: 14 high: 28, mid-latitude: 10, time of max AP: 09:00 UT; Max AP: 6; Sunspot Number: 91; Radio Flux: 154
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 5, 2026
Notable earthquakes and events:
A light geomagnetic storm began around 21:20 UT on January 4. GOES 8 and 9
magnetometers showed about 20% increase in geomagnetic field strength
within about 5 minutes at this time. This storm reached global Kp of 4.3 around 08:00 UT on
January 5 with high latitude K- index of 6 at that time. Sudden commencement storms can help
promote associated enhanced seismicity but generally lead to reduced
seismicity globally in the next two days while systems reconfigure.
A moderately strong earthquake of M 5.2-5.6 shook areas of Assam, India today and
was followed by an M 5.3 aftershock. EMSC reported the mainshock was widely
felt with strong intensity in India at Morigaon, Dhing, Mangaldai, Raha, Dhekiajuli, Alluchawka, Mangoldoi, Tezpur, North Guwahati, Rangapara, Dispur, Hojai, Rangia, Soalkuchi, Palasbari, Nongpoh, Shillong, Mushalpur, Khliehriat, Barpeta Road, Numaligarh, Dimapur, Naharlagun, Badapur, Golaghat, Silchar, Bihpuriagaon, Bongaigaon, Busugaon, Alipur Duar, Moranha, Tinsukia, and in Bangladesh at Sakhipur, Sylhet and in Bhutan at Samdrup Jongkhar, Bhangtar, Daifam,
NEIC reported intensity V in Assam, India at Udalguri, Raha Gaon, ?Nagaon, Hojai, Dhing, Tezpur, Mangaldai, and IV in Gauhati, Sualkuchi, Gohpur, Shillong, Meghalaya, Palaasbari, Sibsagar, Itanagar, Arunachal Pradesh, Dimapur, Nagaland, North Guwahati, with III in Shiliguri, Bangla, Silhat, Bangladesh and Kohima, Nagaland among others and as far as 300 km from the epicenters.
The last earthquake within about 200 km of this event in Assam, India of M>=5.2
occurred as an M 5.5 on September 14, 2025 but the last of significantly
larger magnitude was an M 6.0 on April 28, 2021. At the time this summary noted:
"The strongest earthquake of the day was an M 5.5-5.9 in Assam, India. NEIC reported it was felt with intensity VII in Dhing, Assam, India, V in Tawang, Dispur, Assam and Shillong, Meghalaya, India and in Silhat, Bangladesh, with IV in Itanagar Arunachal Pradesh and Sualkuchi, Assam India and in Rangpur, Bangladesh, and III in Rangapara, India and in Bangladesh at Rungi, Munshiganj, Nalitabari and in Phuentsholing, Bhutan.
EMSC reported strong shaking in India at Mangaldai, Morigaon, Raha, Tezpur, Dispur, Rangia, Guwahati, Soalkuchi, Hajo, Hojai, Nongpoh, Shillong, Barpeta Road, Itanagar, Abhayapuri, Dergaon, Wylhet, Titabar, Karimganj, Jorhat, Lakhimpur, Silchar, Dhubri, Dhemaji, Sibsagar, Imphal, Mymensingh, Bangladesh, and in Bhangtar, Thimphu among others in Bhutan, India, and Bangladesh.
The last earthquake within about 200 km of this epicenter in India with M>=5.5
occurred as an M 6.0 on April 28, 2021. At the time this summary noted:
"The strongest earthquake in the world today was an M 6.0 in Assam, India. The National Center for Seismology (NCS) of India gives this event M 6.4. The mainshock was reported felt with maximum shaking and damage in Assam at Udalguri; VII in Dhekiajuly, Rangapara, Nagaon, VI in Tezpur, Tangla, Raha Gaon and North Guwahati and V in Gauhati, Assam, India
An M 4.7 aftershock was felt with intensity VII in Assam at Tezpur; VI m Gauhati, and Samdrup; V in Dohu, Palasbari, Bondila, Nagaon; IV in Dispur and Shillong, Meghalaya, India.
Cracks appeared in walls, ceilings and floors of some buildings, with some reports
of collapsed ceilings and walls, but there were no immediate reports of casualties. Internet showed
extensive damage in some areas. People fled their homes into the streets
during the earthquake. The last earthquake within about 250 km of today's
activity with M>=6.0 occurred on September 21, 2009, the only such event in this region
in at least 30 years although an M 5.9-6.0 quake hit about 200 km south of this
on May 8, 1997. The last event of larger magnitude in the general area of northern India
was an M 6.9 at intermediate depth on April 13, 2016 in Bangladesh." (April 28, 2021)
This epicenter is located at a longitude which was strongly affected by
the full moon of September 8 (local time) and was probably promoted by tidal stresses
associated with that alignment ...
Today's earthquake occurred near local solar noon.
This epicenter is located near the sixth node (60 degrees) from Kamchatka
and at 143 degrees from the Drake Passage M 7.4 of August 22 and may have been promoted by energy from those sources." (September 14, 2025)
Readers may note the coincidence with the full moon (as with today's event).
This epicenter is at the seventh node from Tropical Cyclone Grant (52 degrees) and
at the eighth node (45 degrees) from Hokkaido, Japan and may have been promoted
by energy from those sources.
O: 04JAN2026 22:47:52 26.3N 92.3E MB=4.9 EMSC ASSAM, INDIA
O: 04JAN2026 22:47:38 26.4N 92.3E MB=5.2 EMSC ASSAM, INDIA
EMSC reported an earthquake of M 3.8 in Central Italy was felt with a loud rumble and intensity up to II-III in the area(s) of Central Italy at Servigliano, Penna San Giovanni, Montappone, San Vittoria in Matenano, Ripe San Ginesio, Sarnano, Amandola, Mogliano, Monte San Pietrangeli, Monte San Giusto, Macerata, Treia, Fermo, Ascoli Piceno, Camerino, Mozzano, San Marco, Porto San Giorgio, Massignano, Grottammare, Massa, Camerano, Posatora.
Several light aftershocks were also felt in the area. EMSC reported they were felt lightly in Italy at Penna San Giovanni, Mogliano, Tolentino, Castignano, Monterubbiano, Porto San Giorgio and Montappone.
This epicenter is at the fifth node (72 degrees) from the Yukon, Canada, TC Grant,
and at 102 degrees from central Philippines and may have been promoted by
energy from those sources.
O: 05JAN2026 02:31:39 43.1N 13.4E ML=3.8 EMSC CENTRAL ITALY
NEIC reported a series of light earthquakes of M 3.0-4.0 in the Virgin Islands was felt with intensity up to II-III in the area.
O: 04JAN2026 10:43:45 19.1N 64.9W MD=3.2 EMSC VIRGIN ISLANDS REGION
O: 04JAN2026 09:06:11 19.2N 64.7W MD=3.4 EMSC VIRGIN ISLANDS REGION
O: 04JAN2026 10:25:47 19.2N 64.8W MD=3.3 EMSC VIRGIN ISLANDS REGION
O: 04JAN2026 11:07:59 19.2N 64.8W MD=3.5 EMSC VIRGIN ISLANDS REGION
O: 05JAN2026 02:56:54 19.3N 64.7W MD=3.7 EMSC VIRGIN ISLANDS REGION
O: 05JAN2026 03:22:02 19.3N 64.6W MD=3.6 EMSC VIRGIN ISLANDS REGION
NEIC reported an earthquake of M 5.2 in Eastern New Guinea was felt with intensity up to II-III in the area(s) of Eastern New Guinea in Lae Morobe and Port Moresby.
This event occurred near local solar noon and may have been promoted by tidal
and/or geomagnetic stresses which maximize near this hour.
This epicenter is at the seventh node (51 degrees) from TC Jenna; the sixth node (60 degrees) from
Kamchatka and the eighth node (45 degrees) from Honshu, Japan and may have been promoted by
energy from those sources.
O: 05JAN2026 00:42:04 5.6S 147.6E MB=5.2 EMSC EASTERN NEW GUINEA REG., P.N.G
NEIC reported an earthquake of M 2.6 in Kentucky was felt with intensity up to II-III in the area(s) of Kentucky with II in Liberty and Somerset, Kentucky and in Tennessee at Cumberland Gap, Harrogate and New Tazewell.
O: 04JAN2026 20:07:15 36.5N 83.8W MD=2.6 EMSC EASTERN TENNESSEE
NEIC reported an earthquake of M 3.3 in northern Utah was felt with intensity up to II-III in the area(s) of northern Utah with III in Huntsville, Eden, Ogden, Salt Lake City, Hooper, Bountiful, Springville, Morgan, Kaysville, Farmington, and II in Matua, Syracuse, Roy, Layton, West Jordan, Clearfield, and Brigham City.
This epicenter is at 142 degrees from TC Jenna and may have been promted by energy from that source.
O: 04JAN2026 14:18:00 41.3N 111.6W ML=3.2 EMSC UTAH
EMSC reported an earthquake of M 4.9 in Colombia was felt with intensity up to IV in the area(s) of Colombia in San Gil, Pinchote, Piedecuesta.
This epicenter is at 145 degrees from Taiwan and the fifth node from Yukon,
Canada and 105 from Kamchatka and may have been promoted by energy from those
sources.
O: 05JAN2026 05:35:40 6.7N 73.0W MB=4.9 EMSC NORTHERN COLOMBIA
EMSC reported an earthquake of M 4.6 in Ethiopia was felt with intensity up to IV in the area(s) of Ethiopia in Mek'ele.
NEIC reported was felt with intensity up to II-III in the area(s) of Tigray Ethiopia at Aksum and Mek'ele.
This earthquake may have been promoted by a moderate solar flare.
It occurred at the peak of flare 7570 (C1.7) near local solar midnight.
SWPC parameters for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7570 1959 2007 2013 C1.7 (January 4, 2026) 1.4E-03
Ethiopia M 3.4 20:05 UT
This earthquake may also have been promoted by the full moon of January 3
as it occurred near the longitude of maximum tidal stress with this
alignment as reported in previous issues of this summary:
"The full moon arrived on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026." (January 1-3, 2026)
This epicenter is at the fourth node (90 degrees) from Hokkaido, Japan; the sixth node
(60 degrees) from TC Jenna and 106 degrees from Yukon, Canada and may have been
promoted by energy from those sources.
O: 04JAN2026 20:05:35 13.6N 39.8E MB=4.5 EMSC ETHIOPIA
The strongest earthquake in the western hemisphere today was an M 4.8 near
the coast of Nicaragua. It was not reported felt. This event may have
been promoted by the passage of Tropical Cyclone Jenna at the antipode
of this epicenter as reported in this summary:
"TC JENNA 2026-01-05 00:00 UT 12.2S 94.1E 55 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 55 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 12N 86W - an area of Costa Rica and Nicaragua. These areas are active at this time and a moderate antipodal earthquake in this area is likely in the next three days." (January 5, 2026)
In addition to being nearly antipodal to TC Jenna this epicenter is located at the sixth node from Yukon, Canada and the fourth node (90 degrees) from Kamchatka and may have been promoted by energy from those sources.
O: 04JAN2026 14:20:30 12.6N 87.8W MB=4.8 EMSC NEAR COAST OF NICARAGUA
The strongest earthquake of the day was an M 5.7 in the Prince Edward Island
area of the South Indian Ocean. It was not reported felt in this remote
epicentral area. This event also occurred near the longitude
of maximum tidal stress with the full moon of January 3, 2026. It is symmetric
about the equator with an M 4.0 in the Caucasus today (see below).
The last earthquake in the Prince Edward Islands region within about 200
km of today's epicenter with M>=5.7 occurred as an M 6.2 on May 31, 2024.
A significant earthquake of M 6.8 hit the region on May 21, 2023.
At the time this summary noted:
"The strongest earthquake in the world today was an M 6.8 in the Prince Edward
Islands of the South Indian Ocean. It was not reported felt in this remote area.
This is the strongest earthquake in the Prince Edward Islands region within about
300 km of these epicenters in at least 35 years. The largest previous earthquake
in this time frame in this area was an M 6.3 exactly 25 years ago today on
May 21, 1998 within about 200 km of today's epicenter." (May 21, 2023)
This epicenter is at 102 degrees from Taiwan (Node 7) and at the sixth node from
TC Jenna and may have been promoted by energy from those sources.
O: 04JAN2026 13:07:06 43.4S 39.2E MW=5.7 EMSC PRINCE EDWARD ISLANDS REGION
EMSC reported an earthquake of M 3.0 in northern California south of San Francisco was felt with intensity up to IV in the area(s) of northern California south of San Francisco in Day Valley, Aptos Hills, Larkin Valley, Aptos. Seacliff, Soquel, Live Oak, Twin Lakes, Santa Cruz, San Martin.
This earthquake may have been promoted by a moderate solar flare - the strongest
of the day as it occurred near local solar noon at the peak of flare 7580 - a C2.8
event. Data for this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7580 2051 2101 2109 C2.9 (January 4, 2026) 2.5E-03
No. California M 2.8 21:14 UT
Michoacan M 4.1 21:15 UT
This epicenter is located at 102 degrees from central Philippins and a the fifth node (72 degrees) from
Honshu, Japan and may have been promoted by energy from those sources.
O: 04JAN2026 21:14:16 37.0N 121.8W MD=2.8 EMSC NORTHERN CALIFORNIA
The earthquake in the Caucasus of M 4.0 today (see above) was reported felt lightly in Russia at Lazarevskoye, and Sochi.
Like the earthquake in northern California (see above) this epicenter is at
the fifth node (72 degrees) from Honshu (and Kamchatka) and may have been
promoted by energy from those sources.
O: 04JAN2026 09:47:10 43.9N 39.4E ML=4.0 EMSC CAUCASUS REGION, RUSSIA
EMSC reported an earthquake of M 4.1 in northern Chile was felt with intensity up to IV in the area(s) of northern Chile at Arica.
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE JENNA (12S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC JENNA 2026-01-05 00:00 UT 12.2S 94.1E 55 kts South Indian Ocean
Tropical Cyclone Jenna (12S) continued today in the region of the south Indian Ocean winds up to 55 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 12N 86W - an area of Costa Rica and Nicaragua. These areas are active at this time and a moderate antipodal earthquake in this area is likely in the next three days.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2026-01-05 00:00 UT 16.1S 59.7E 40 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 40 kts off the east coast of Madagascar. The antipode is at 16N 120W - is in an aseismic section of the North Pacific Ocean.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 4, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7490 1047 1055 1105 C1.6 (January 4, 2026) 1.6E-03
South Sandwich Is. M 4.7 10:36 UT
Guerrero M 4.0 10:46 UT
Kamchatka M 5.1 11:01 UT
Baja California M 3.4 11:01 UT
7550 1522 1525 1527 C1.7 (January 4, 2026) 6.0E-04
Arizona M 2.7 15:35 UT
7560 1740 1821 1844 C1.9 (January 4, 2026) 6.9E-03
Southern Italy M 3.7 17:48 UT
Kamchatka M 4.3 17:55 UT M 4.4 18:07 UT
7570 1959 2007 2013 C1.7 (January 4, 2026) 1.4E-03
Ethiopia M 3.4 20:05 UT
Kuril Is. M 4.2 20:12 UT
No. California M 2.4 20:01 UT
7580 2051 2101 2109 C2.9 (January 4, 2026) 2.5E-03
No. California M 2.8 21:14 UT
Michoacan M 4.1 21:15 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled conditions January 5 quiet January 6-7, 2026. Solar M-flare chance: 50% X-class: 10% proton storm: 10%
AP Indicies: global: 6 high: 2, mid-latitude: 4, time of max AP: 23:00 UT; Max AP: 3; Sunspot Number: 97; Radio Flux: 157
A light geomagnetic storm began around 21:20 UT on January 4. GOES 8 and 9
magnetometers showed about 20% increase in geomagnetic field strength
within about 5 minutes at this time. This storm reached global Kp of 4.3 around 08:00 UT on
January 5 with high latitude K- index of 6 at that time. Sudden commencement storms can help
promote associated enhanced seismicity but generally lead to reduced
seismicity globally in the next two days while systems reconfigure.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 4, 2026
Notable earthquakes and events:
In the past several issues, this summary has followed the continuing activity
in Northern Japan with interest. This is a continuing series which began
on November 9, 2025 (M 6.8) with ensuing events on December 8, 2025 (M 7.6)
and December 31, 2025 (M 6.0). A further strong earthquake in this series is possible
but unlikely (unless a major unexpected solar flare occurs) around January 6-8, 2026 in the northern Honshu to Hokkaido area.
These events have been associated with major solar flares of high M-class to X-class and appear to be related to a sunspot
group rotating with the sun. If this continues a second time for another such event
would be around January 23-27, 2026. This would be most likely to the northeast
of the current series in the Southern Kuril Islands. This summary will continue
to monitor this region for changes in this pattern.
The strongest earthquake felt in the world today was an M 4.7 in Eastern Turkey.
NEIC reported it was felt in Turkey with intensity III in Elazig and II in Gaziantep.
EMSC reported moderate to strong shaking in eastern Turkey in Kale, Kussarayi, Elazig, Battalgazi, Malatya, Yesilyurt, Akincilar, Ergani, Adiyaman, Kayapinar, Sur, Karakopru, Sanliurfa, Suruc, Birecik, Sehitkamil, and in Syria at Manbij and Aleppo.
The last earthquake within about 200 km of this epicenter with M>=4.7 occurred
as an M 4.7 on April 27, 2025. These appear to be aftershocks of an M 6.0
of October 16, 2024. At the time this summary noted:
The strongest earthquake in the world today was an M 6.0 in eastern Turkey. NEIC reported maximum intensity VII (with damage) was felt in Turkey at Elazig and Malatya with V in in Yesilyurt. Intensity IV was reported in Diyarbakir, Erzincan, Gaziantep with intensity II-III in Doganyol, Malatya and Sivric, Elazig and Mazidagi, Mardin, and Ordu, Turkey.
EMSC reported this event was widely and strongly felt in eastern Turkey at Bulgurlu, Zaviye, Atasehir, Dilek, Yesilyurt, Caydacira, Universite, Elazig, Dilek, Kirklar, Girne, Eskisaray, Adiyaman, Varlik, Aktuluk, Kuptepe, Yaslica, Yaytas, Yenikent, Atakent, Firat, Diclekent, Fabrika among others within about 400 km of the epicenter. Also reported lightly felt in Iraq, Syria, Georgia, Lebanon, Cyprus.
The mainshock was accompanied by a series of foreshocks and aftershocks suggesting
strong regional stresses at this time. This included an M 4.3 yesterday reported
in this summary as:
"NEIC reported this earthquake of M 4.3 in Eastern Turkey was felt with intensity up to IV in the area(s) of Eastern Turkey in Doganyol and Agin Elazig.
EMSC reported light shaking in Turkey at Hilalkent, Atasehir, Abdullah Pasa, Sursuru, Cumhuriyet, Universite, Rizaiye, Firat, Yurukselim." (October 15, 2024)
This is the strongest earthquake in the region of Europe or the Middle East
since February 20, 2023 when an M 6.3 occurred about 300 km southwest of today's
epicenter and February 6, 2023 when the last earthquake in eastern Turkey within about 200 km of today's epicenter
occurred as an M 6.0 on February 6, 2023 - an aftershock of the major events of M 7.8 and M 7.5
in the area of February 6, 2023 and is the strongest aftershock of that
activity since the M 6.0 of February 6, 2023. At the time this summary noted:
"The major earthquake activity in Turkey and Syria continued today with an aftershock of M 7.5-7.6 to the M 7.8 reported in the previous issue of this summary.
Nearly 8700 are now confirmed dead in Turkey (6234) and Syria (2500) from these earthquakes and this number expected to continue to rise as hundreds are still trapped below rubble.
Estimated death tolls could reach 20,000 in the area. There is little available fuel or electricity in the area, nearly the area of
the northeast U.S. The last earthquake causing as many deaths was an M 9.0 in Japan
with a massive tsunami on March 11, 2011. An earthquake of M 7.0 in Haiti in
January, 2010 is estimated to have taken the lives of 220,000-320,000 people. More than 20,000
were injured with thousands of structures damaged or destroyed according to latest
estimates. The number of displaced people - including refugees - affected by these
earthquakes numbers in the hundreds of thousands. Regional airports are only
servicing rescue aircraft. All civilian planes have been grounded. Arrival of aid
is also hampered by civil unrest in Turkey and Syria. Internet photos show large
areas of complete devastation. The earthquake occurred during
harsh winter weather and a cholera epidemic which are expected to continue. Today's event of M 7.5-7.6 occurred near local solar noon and was probably promoted by strong tidal stresses which
maximize near this hour with the full moon." (February 6, 2023)
Like the earthquakes of February 6, 2023, today's event also occurred within about
a day of the full moon and was probably promoted by tidal stresses associated with
this alignment as it occurred within about an hour of local solar noon, a time
when tidal stresses maximize.
...
Today's earthquake in Turkey follows a major series of geomagnetic storms
and may also have been promoted by geomagnetic effects as noted in previous
issues of this summary for example:
"The current geomagnetic storm - the strongest in the world since AP at high
latitudes occurred reached 91 and planetary AP reached 122 on August 8, 2024 -
continued today with high latitude AP 116. Severe storms are expected through
October 11 with minor storms October 12. Maximum Kp during the storm reached
Kp 9 - the highest of the scale around 18:00 UT shortly after the arrival
in the earth environment of the CME from the X9.0 flare of early October. Global seismic
conditions are expected to remain relatively quiet through the storm with
a likely temporary enhancement with the arrival of the CME early on October 10
and should increase significantly shortly after the end of the geomagnetic storm
on October 12-15." (October 10-12, 16 2024)
Readers may note this previous event in eastern Turkey occurred with
the full moon and strong geomagnetic disturbance.
Today's event also occurred near the longitude of maximum tidal stress with the
full moon of January 3, 2026 and may have been promoted by tidal stresses
with that alignment as noted in previous issues of this summary:
"The full moon arrived on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026." (January 1-3, 2026)
This event in Turkey also appears to have been promoted by a moderate solar
flare (#7350, C8.3). This is the largest solar flare in several days as
reported by SWPC. The earthquake in Turkey occurred at the maximum output
of this flare as recorded with the following parameters by SWPC:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7350 1723 1729 1732 C8.3 (January 3, 2026) 2.8E-03
Eastern Turkey M 3.7 17:27 UT
This epicenter is at the sixth node (60 degrees) from Tropical Cyclone Grant and at the
fifth node (72 degrees) from Taiwan and may have been promoted by energy from
those sources.
O: 03JAN2026 17:27:29 38.4N 38.9E MW=4.7 EMSC EASTERN TURKEY
The strongest earthquake in the world today occurred as an M 5.9 in the Southeast Indian
Ridge. It was not reported felt in this remote area. This appears to be an aftershock
of an M 6.1 south of this epicenter which occurred on January 1, 2026. At the time
this summary noted in this regard:
"NEIC reported an earthquake of M 6.0 in the Southeast Indian Ridge was not felt in this
remote epicentral area. It occurred in late solar morning in this epicentral area (January 1, 2026). This is the strongest earthquake within about 300 km
of this epicenter in the Indian Ridge since an M 6.3 on March 24, 2018 and priot to that an M 6.4 on
November 10, 2010. At the time this summary noted:
"An earthquake in the South Indian Ocean of M 6.2-6.3 was also well forecast to occur
at this time. This is a remote area and this event was not reported felt. It
occurred near local solar midnight and tidal stresses may have helped promote
this event as did geomagnetic effects at this high latitude. The last earthquake
within about 200 km of this epicenter with M>=6.3 was an M 6.5 on November 10, 2010. Other quakes hit the
region with M 6.3-6.5 on October 29, 2005 and February 18, 1994. The antipode
of this event is in southern Ontario, Canada near Ohio at 45N 84W. A light
sympathetic quake could occur near this epicenter in the next several days." (March 24, 2018)
Today's epicenter in the Southeast Indian Rise is at the fifth node (72 degrees)
from Taiwan; the sixth node (60 degrees) from Mindanao and the 10th node (36 degrees)
from Tropical Cyclones Iggy and Grant in addition to 144 degrees from Yukon, Canada and may have been promoted by
energy from those sources." (January 1, 2026)
O: 03JAN2026 10:07:57 45.4S 96.5E MW=5.9 EMSC SOUTHEAST INDIAN RIDGE
NEIC reported an earthquake of M 4.4 in Southern Peru was felt with intensity up to II-III in the area(s) of Southern Peru in Chincha Alta Ica.
O: 03JAN2026 20:17:53 14.6S 76.3W MB=4.4 EMSC NEAR COAST OF CENTRAL PERU
NEIC reported an earthquake of M 4.2 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan in Taipei.
O: 03JAN2026 19:52:50 24.7N 121.8E ML=4.4 EMSC TAIWAN
NEIC reported an earthquake of M 2.6 in Central California was felt with intensity up to II-III in the area(s) of Central California in Marina.
O: 03JAN2026 14:09:46 36.5N 121.1W MD=2.6 EMSC CENTRAL CALIFORNIA
EMSC reported an earthquake of M 4.2 in Bio-Bio, Chile was felt with intensity up to IV in the area(s) of Bio-Bio, Chile in Lebu.
EMSC reported an earthquake of M 4.6 in Ecuador was felt with intensity up to IV in the area(s) of Ecuador in Riobamba.
O: 03JAN2026 08:46:49 1.9S 78.9W MB=4.5 EMSC ECUADOR
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE 12S
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 12S 2026-01-04 00:00 UT 9.0S 95.2E 50 kts South Indian Ocean
Tropical 12S formed today in the region of the south Indian Ocean winds up to 50 kts south of Sumatra. Increased seismicity south of Sumatra is possible but unlikely at this time. The antipode is at 9N 85W - is south of Panama in an area where a moderate earthquake is possible at this time. TC 12S will then move to the south over the next two days putting it antipodal to Costa Rica and Nicaragua. These areas are active at this time and a moderate antipodal earthquake in this area is likely in the next three days.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2026-01-04 00:00 UT 16.0S 62.2E 45 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 45 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely at TC Grant passes to the north in the next days but should cease as TC Grant makes landfall in Madagascar on January 5-6. The antipode is at 16N 118W - is south of The Gulf of California, Mexico where enhanced antipodal activity north of this epicenter is possible but unlikely at this time.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 3, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7270 0127 0137 0152 C2.9 (January 3, 2026) 3.6E-03
New Guinea M 5.0 01:26 UT
Guerrero M 4.3 01:35 UT
Papua M 3.5 01:30 UT
7280 0606 0619 0637 C2.3 (January 3, 2026) 4.2E-03
Tonga M 4.7 06:16 UT
Tonga M 4.7 06:15 UT
7300 0637 0643 0647 C2.5 (January 3, 2026) 1.7E-03
7290 0741 0749 0755 C2.0 (January 3, 2026) 1.7E-03
Southern California M 2.0 07:44 UT
7340 1451 1458 1507 C2.4 (January 3, 2026) 2.2E-03
7350 1723 1729 1732 C8.3 (January 3, 2026) 2.8E-03
Eastern Turkey M 3.7 17:27 UT
7360 1856 1909 1919 C1.7 (January 3, 2026) 2.3E-03
Gulf of Aden M 4.5 19:10 UT
7370 2026 2038 2045 C3.5 (January 3, 2026) 3.2E-03
Talaud M 4.8 20:46 UT
7390 2215 2219 2224 C1.7 (January 3, 2026) 1.0E-03
New Britain M 5.0 22:25 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms January 4 and unsettled conditions January 5 quiet January 6, 2026. Solar M-flare chance: 50% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 12 28 10 18:00 6 136 165
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 3, 2026
Notable earthquakes and events:
In the issue of this summary on December 30, 2025 the following was stated:
"SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE HAYLEY (10S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC HAYLEY 2025-12-30 00:00 UT 16.5S 122.0E 110 kts North of western Australia
Tropical Cyclone Hayley (10S) continued today in the region north of western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 16N 58W - is in the area of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-30 00:00 UT 14.3S 78.3E 135 kts South of India
Tropical Cyclone Grant (09S) continued today in the region south of India winds up to 135 kts as a suddenly forming major storm. The antipode is at 15N 102W - is east of Central America and south of Guerrero, Mexico where enhanced antipodal activity is possible." (December 30, 2025)
These were the only tropical cyclones active on that date in the world. This
is notable because today January 2, 2026 the two largest earthquakes of
the current year occurred in Guerrero, Mexico (M 6.5) and Martinique/Guadeloupe (M 5.5).
These appear to be consistent with antipodal focusing of energy from the two
tropical cyclones noted above.
These areas also show consistent triggering at times of lunar-solar alignments
and these earthquakes were probably promoted by the full moon tidal stresses
of January 3 as noted in previous issues of this summary as:
"The full moon will arrive on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026." (January 1-2, 2026)
The strongest earthquake in the world today was an M 6.5 in Guerrero, Mexico. NEIC
reported it was felt widely with damage in Guerrero and intensity up to VIII in Ayutla, VI in Chilapa, V in Acamixtla, Acapulco, Tlapa, Chjilpancingo, Cuautitlan, Totolapan and in Mexico City; IV in Puebla Mexico at Teziutlan, Ocoyucan, Momoxpan, Taxco, in Uruapan, Ocampo, Michoacan, in Mexico City area at Xico, Nezahualcoyotl, Metepec, Buenavista, Mesico City, Atenco, Naucalpan and III in Tlaxcala, Oxaca, Jalisco, Michoacan, Querretaro, Veracruz, Morelos, Guanajuato, Hidalgo, Coatepec, Los Reyes, and as far as 700 km from the epicenter.
A number of moderate aftershocks were also lightly felt in the area of Guerrero.
Press reports (BBC) report at least two were killed in the earthquake with one
in Mexico City where 12 were injured. Minor damage to built structures was
extensive but only two buildings appeared to be likely to collapse although
39 others were being assessed for possible demolition. Roads and hospitals
were impacted with many landslides on roads in Guerrero State.
This is the strongest earthquake in the area of Guerrero within about 250 km
of this epicenter since an M 7.0 on September 8, 2021. At the time this summary
noted:
"A major earthquake of M 7.0 shook the region of Guerrero, Mexico south of Mexico City today.
A foreshock of M 4.2 occurred several hours before the mainshock and was felt in Guerrero with IV at Acatlan, Zihuatanejo, Coatepec,Mexico City and II-III in Tlapa, Santos Reys, Oaxaca, Vista Hermosa, Naucalpan, Chautla, Puebla and in Cuernavaca, Morelos, Mexico.
NEIC reported the mainshock was felt with maximum intensity VII with slight damage in Guerrero, Mexico at Acapulco, Chipancingo, and VI i El Ocotilo, Tepecoacuillc, Tizapotla and Taxco with IV in Tlapa and Huamuxtitlan and II-III in Xaltianguis and Petatlan and in Mexico City.
A number of aftershocks were lightly felt in the Mexico City and Tlalnepantla, Mexico area.
Reuters reported at least one person died in the quake when a pole fell on him.
The earthquake was centered near Acapulco, Mexico and caused damage as far
north as Mexico City with landslides. Tall buildings swayed and cars were crushed
by falling debris. A tsunami alert was not issued but minor sea level fluctuations
may have occurred. No earthquakes of M>=7 have occurred within about 100 km
of today's epicenter in the past 30 ye3ars. Earthquakes within about 250
km of this occurred about 250 km northeast on September 19, 2017 and to the northwest on April 18, 2014.
Similar events hit to the east of this on March 20, 2012 (M 7.4); February 25, 1996 (M 7.1) and September 14,
1995 (M 7.4). This earthquake occurred with the new moon and was
probably promoted by strong tidal stresses associated with that alignment.
...
A Tropical Depression made landfall off the coast of Guerrero, Mexico about
the time of the M 7.0. Stresses associated with this storm probably also
helped promote seismicity in this region of Mexico at this time as reported
in this summary as:
"Tropical Depression 15E formed south of western Mexico today with winds up to 40 kts. This system is expected to track to the north and west and may enhance seismicity in western and central Mexico. The M 7.0 in Guerrero, Mexico today may have been promoted by stresses associated with this storm." (September 6-7, 2021)
A series of moderate earthquakes north of this epicenter has been occurring
over the past two days. It is likely that this was precursory to today's
event in Guerrero, Mexico." (September 8, 2021)
Prior to that an M 7.1 occurred north of this epicenter on September 19, 2017 (also with the new moon).
This was discussed in this summary at the time as:
"The timing of today's earthquake near local solar noon in conjunction with the
new moon alignment strongly suggests tidal triggering to this event.
...
"... today's event of M 7.1 also was associated with
strong geomagnetic activity. ... occurred as the CME from the strongest
flare in 12 years hit the earth. Geomagnetic activity also peaked yesterday
at the strongest levels (KP 7) since September 8 and was probably also
promotional to the Mexican earthquake today as noted in the previous summary:
"The geomagnetic field was at active conditions today. The AP level was 22.
High latitude geomagnetic field saw major storms with AP at 51.
Strong seismicity is still possible within 10-15 degrees from the geomagnetic
equator and at high auroral latitudes around September 18-21." (September 19, 2017)
In addition to being antipodal to Tropical Cyclone Grant, this epicenter
in Guerrero, Mexico is also near 102 degrees from northern Japan, and at the seventh
node (52 degrees) from the Yukon, Canada and the third node (120 degrees)
from Taiwan and may have been promoted by energy from those sources.
A listing for events in this series of M>=4 follows. A more complete listing
can be found in the Data section of this report.
O: 02JAN2026 13:58:18 16.9N 99.3W Mw=6.5 EMSC GUERRERO, MEXICO
O: 02JAN2026 13:58:18 16.9N 99.3W MB=6.5 NEIC GUERRERO, MEXICO
O: 02JAN2026 21:42:06 16.6N 99.5W ML=4.0 EMSC OFFSHORE GUERRERO, MEXICO
O: 02JAN2026 14:17:32 16.7N 99.5W ML=4.2 EMSC GUERRERO, MEXICO
O: 02JAN2026 16:28:45 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 19:25:12 16.7N 99.5W ML=4.0 EMSC OFFSHORE GUERRERO, MEXICO
O: 02JAN2026 20:53:34 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 21:18:20 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 21:37:27 16.7N 99.5W ML=4.1 EMSC OFFSHORE GUERRERO, MEXICO
O: 02JAN2026 23:06:45 16.7N 99.5W ML=4.0 EMSC OFFSHORE GUERRERO, MEXICO
O: 03JAN2026 00:34:11 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 03JAN2026 00:37:48 16.7N 99.6W ML=4.1 EMSC GUERRERO, MEXICO
O: 03JAN2026 00:59:49 16.7N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 03JAN2026 02:43:14 16.7N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 03JAN2026 02:57:48 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 03JAN2026 03:03:00 16.7N 99.6W ML=4.1 EMSC GUERRERO, MEXICO
O: 03JAN2026 03:06:56 16.7N 99.6W ML=4.0 EMSC GUERRERO, MEXICO
O: 03JAN2026 07:15:22 16.7N 99.5W ML=4.0 EMSC OFFSHORE GUERRERO, MEXICO
O: 03JAN2026 07:28:40 16.7N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 14:46:54 16.8N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 15:08:42 16.8N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 02JAN2026 15:37:08 16.8N 99.2W ML=4.4 EMSC GUERRERO, MEXICO
O: 02JAN2026 16:24:09 16.8N 99.5W ML=4.0 EMSC GUERRERO, MEXICO
O: 02JAN2026 16:36:07 16.8N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 02JAN2026 16:43:19 16.8N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 02JAN2026 17:00:35 16.8N 99.4W mb=4.5 EMSC GUERRERO, MEXICO
O: 02JAN2026 21:19:57 16.8N 99.5W ML=4.2 EMSC GUERRERO, MEXICO
O: 03JAN2026 01:29:47 16.8N 99.5W ML=4.1 EMSC GUERRERO, MEXICO
O: 03JAN2026 01:34:49 16.8N 99.5W ML=4.3 EMSC GUERRERO, MEXICO
O: 02JAN2026 15:34:18 16.9N 99.3W mb=4.2 EMSC GUERRERO, MEXICO
The M 5.5 in the Leeward Islands near Martinique and Guadeloupe today was reported felt in Martinique with intensity V in Le Marin, IV in La Trinite, Saint-Pierre, Saint-Joseph, Fort-d-France, Schoelcher, Le Francois, Les Trois-Ilets, Le Robert and in Castries, Saint Lucia.
EMSC reported a loud noise and strong shaking in Martinique at La Trinite, Le Robert, Le Francois, Le Lorrain, Le Gros-Morne, Le Vauclin, Saint-Joseph, Le Lamentin, Basse-Pointe, Ducos, Saint-Esprit, Ducos, Fort-de-France, Schoelcher, among others.
The last earthquake within the area of Martinique within about 150 km of today's
epicenter with M>=5.5 occurred on February 3, 2017. At the time this summary noted:
"A moderate earthquake of M 5.6 hit the region of Martinique in the eastern Caribbean
today. NEIC reported it was felt with maximum intensity VI in Le Lamentin, Fort-de-France, Martinique and V in Fort-de-France, Saint-Pierre, Schoelcher, Riviere-Salee and Le Robert, La Trinite, Martinique and in Dennery and Cap Estate, Gros Inlet, Saint Lucia. Intensity IV was reported from La Trinite, Le Lorrain, Ducos, Guadeloupe; in Byera, Saint Vincent and the Grenadines; Point-a-Pitre, Grande-Terre, Guadeloupe; Choc, Castries, Saint Lucia. It was also reported lightly felt with intensity II-III in Marginique at Gros-Morne, La Vauclin, Saint-Joseph, Rivere-Pilote, La Plaine, Martinique; in Dominica at Castle Bruce, Saint David, Marigot and Calibishie, Saint Andrew; Portsmouth, Saint John, Canefield, Saint Paul; Roseau, Saint George; Marigot, Saint Andrew, Dominica;
in Saint Lucia at Cap Estate, Gros Islet, Castries, Choc, Soufriere, Saint Lucia; Capesterre-Belle-Eau, Gourbeyre, Le Gosier, Basse-Terre, Saint-Claude, Petit-Bourg, Baie-Mahault, Sainte-Rose, Guadeloupe; in Saint Vincente and the Frenadines at Kingstown, Saint George and in Bridgetown, Saint Michael, Barbados and Orocovis, Puerto Rico.
The mainshock followed a light regional event of M 3.9 in Saint Kitts and Nevis and some
of the stated felt activity with the Martinique event may refer to the Saint
Kitts and Nevis earlier event. The last event in the Martinique region of M>=5.6
occurred on October 18, 2016 and prior to that an M 5.6 on December 8, 2015 and December 19, 2014.
The last event of M>5.6 in the area was an M 7.4 on November 27, 2007." (February 3, 2017)
Today's earthquake in Martinique occurred as a moderate geomagnetic storm reaching Kp 5 hit. The GOES-19 and GOES-18
magnetometer shows a sudden decline in geomagnetic field strength of about 50% beginning
around 21:40 UT and ending about 22:00 UT. The earthquake in Martinique
occurred during this geomagnetic field decline.
A small foreshock in the Guadeloupe area preceded today's M 5.5 and was reported
in the previous issue of this summary as:
"EMSC reported an earthquake of M 3.2 in the Leeward Islands near Guadeloupe was felt with intensity up to IV in the area(s) of Guadeloupe.
This epicenter is at the position of the antipode of Tropical Cyclone Hayley
on December 30, 2025. It is likely it was promoted by antipodal focused
energy from that source as reported at the time in this summary:
"TC HAYLEY 2025-12-30 00:00 UT 16.5S 122.0E 110 kts North of western Australia
Tropical Cyclone Hayley (10S) continued today in the region north of western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 16N 58W - is in the area of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow." (December 30,, 2025)
This area of the Caribbean is active and a further moderate earthquake
could still occur near this epicenter in the next several days.
This epicenter is located at 144 degrees from TC Grant, the fifth node (72 degrees) from the Yukon, Canada; the third
node (120 degrees) from Hokkaido and at 103 degrees from Kamchatka and
may have been promoted by energy from those sources." (January 1-2, 2026)
O: 02JAN2026 21:48:26 15.1N 60.5W MB=5.5 NEIC MARTINIQUE
Planetary K-index reached 5.0 (G1 geomagnetic storm levels) late in the UT day
maximizing around 21:50 UT which may have triggered the M 5.5 in Martinique. A second sudden decline in the GOES magnetometer geomagnetic field strength. Today's storm began with K-index at high latitudes around
14:00 UT. This may have triggered a strong earthquake in Guerrero, Mexico
which coincided with the sudden commencement of this storm.
NEIC reported an earthquake of M 3.4 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii with III in Pahala, Honokaa, Pepeekeo, and II in Holualoa, Kailua Kona, Captain Cook, Hilo, Papaikou, Laupahoehoe and Kealakekua.
EMSC reported it was felt strongly in Hawaiian Ocean View and Honoka'a.
This epicenter is at 102 degrees from TC Iggy and may have been promoted by
energy from that source.
O: 02JAN2026 08:00:13 19.2N 155.4W MB=3.6 NEIC HAWAII
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2026-01-03 00:00 UT 15.0S 64.2E 45 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 45 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely at TC Grant passes to the north in the next two days. The antipode is at 15N 116W - is south of The Gulf of California, Mexico where enhanced antipodal activity is possible.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 2, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7120 0008 0017 0023 C6.5 (January 2, 2026) 3.9E-03
South Sandwich M 5.0 00:20 UT
Andreanof Is. M 3.7 00:17 UT
Eastern Turkey M 1.9 00:09 UT
7130 0057 0104 0108 C1.9 (January 2, 2026) 1.2E-03
San Francisco M 3.0 00:59 UT
7140 0141 0147 0150 C1.9 (January 2, 2026) 1.1E-03
7150 0245 0255 0259 C5.5 (January 2, 2026) 2.8E-03
Molucca Sea M 3.7 03:00 UT
7160 0352 0357 0403 C5.7 (January 2, 2026) 2.8E-03
Myanmar M 3.7 04:0 UT
7190 0907 0914 0916 C1.8 (January 2, 2026) 1.5E-03
7200 0916 0925 0937 C2.2 (January 2, 2026) 2.9E-03
Kuril Is. M 4.2 09:34 UT
Guerrero M 3.9 09:34 UT
Molucca Sea M 3.8 09:26 UT
7230 1238 1249 1255 C1.7 (January 2, 2026) 1.7E-03
7250 2048 2054 2058 C2.1 (January 2, 2026) 1.3E-03
Guerrero M 4.0 20:54 UT
Ecuador M 3.6 20:59 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: major storms January 3, 2026 with minor storms January 4 and unsettled conditions January 5, 2026. Solar M-flare chance: 50% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 24 29 16 19:00 5 124 166
Planetary K-index reached 5.0 (G1 geomagnetic storm levels) late in the UT day
maximizing around 21:50 UT which may have triggered the M 5.5 in Martinique. A second sudden decline in the GOES magnetometer geomagnetic field strength. Today's storm began with K-index at high latitudes around
14:00 UT. This may have triggered a strong earthquake in Guerrero, Mexico
which coincided with the sudden commencement of this storm.
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 2, 2026
Notable earthquakes and events:
The full moon will arrive on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are located near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026.
The strongest earthquake in the U.S. or Canada today was an M 5.7 followed by an M 5.3 in southeastern Alaska.
NEIC reported it with felt with intensity III in Whitehorse and IV in Haines Junction, Yukon Territory, Canada and in Alaska with III in Yakjutat, Haines, Copper Center and lightly in Elfin Cove.
EMSC reported light shaking in Juneau, Alaska. This is the strongest aftershock to date of the M 7.0 of December 6, 2025
in the Yukon Territory, Canada although a similar event of M 5.7-5.8 occurred on December 8, 2025. A series of increasingly large aftershocks has occurred in this area over the
past several days as reported in the previous issue of this summary:
"The strongest earthquake in the U.S. or Canada today was an M 5.1 in southeastern Alaska
along the border with Yukon Territory, Canada. NEIC reported this event
was felt with intensity III in Yukon, Canada at Whitehorse and Haines Junction with II.
It follows a slow increase in regional seismicity over the past two days
as reported in the previous issue of this summary:
"The strongest earthquakes in the U.S. or Canada today were a series about 200 km outside the
aftershock zone southeast of the M 7.0 in the Yukon, Canada event of December 6, 2025.
These events of M 3.5 and 3.6 follow an M 4.6 in the region yesterday. That event
is the strongest aftershock of the December 6 mainshock since an M 4.7 on December
10, 2025. Recent increases in solar activity may indicate activation of the
area with the possibility of a further event of M>=5 in the next couple of
days. Today's earthquakes were probably felt with intensity up to III in the Elfin Cove area of
Alaska as per NEIC data.
These epicenters are at the seventh node (52 degrees) from Hokkaido
and may have been promoted by energy from that source." (December 29-30, 2025)
The M 5.7 in the Yukon Territory, Canada may have been promoted by a moderate
C5.3 solar flare - the second largest of the day as it occurred near the peak
output of this flare. SWPC reported the following parameters for this solar flare:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7010 0642 0648 0651 C5.3 (January 1, 2026) 2.3E-03
Yukon M 5.3 06:55 UT
Yukon M 5.7 06:47 UT
Today's event of M 5.0 is located at 105 degrees from Tropical Cyclone Hayley
and may have been promoted by energy from that source as well as from Honshu, Japan." (December 31, 2025)
Today's epicenter of the M 5.7 is located at the fifth node (72 degrees) from
Taiwan and may have been promoted by energy from that source.
O: 01JAN2026 06:46:53 60.5N 140.0W Mw=5.7 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:54:58 60.5N 140.1W Mw=5.3 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:02:52 60.5N 139.9W ML=3.6 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:08:30 60.5N 140.1W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:11:42 60.5N 140.1W ML=3.4 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:17:01 60.5N 140.2W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:25:02 60.5N 139.9W ML=3.9 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:36:48 60.5N 139.9W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:52:35 60.5N 140.1W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 08:26:08 60.5N 140.2W ML=3.1 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 08:48:24 60.5N 140.1W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 12:52:18 60.5N 140.0W ML=4.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 22:54:34 60.5N 140.0W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 02JAN2026 01:35:55 60.5N 139.9W ML=3.9 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 02JAN2026 05:52:12 60.5N 139.9W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:05:28 60.6N 140.2W ML=3.3 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:10:13 60.6N 139.9W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 15:48:48 60.6N 140.4W ML=3.1 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 16:40:06 60.6N 139.9W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 02JAN2026 07:50:17 60.6N 139.9W ML=3.1 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:54:37 60.4N 140.2W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANA
P: 01JAN2026 178576 61.0N 140.0W 3.2-5.3 AAAAA Central Alaska
P: 03JAN2026 178576 60.3N 139.6W 3.2-5.2 AAAAA Central Alaska
NEIC reported an earthquake of M 3.1 in Baja California was felt with intensity up to II-III in the area(s) of Baja California in Reacomodo, Mexico.
This epicenter is located at 102 degrees from Taiwan; the sixth node (60 degrees)
from Kamchatka and at 60.0 degrees from the North Geomagnetic pole and
may have been promoted by energy from those sources.
O: 02JAN2026 02:33:01 32.4N 115.2W ML=2.4 EMSC BAJA CALIFORNIA, MEXICO
O: 01JAN2026 08:02:18 31.4N 115.6W ML=3.1 EMSC BAJA CALIFORNIA, MEXICO
NEIC reported an earthquake of M 3.1 in San Francisco, California was felt with intensity up to II-III in the area(s) of San Francisco, California with IV in Diablo, III in San Ramon, Danville, Oakland, Dublin, Pleasanton, Oakland, Clayton, Concord, Lafayette, and II in Alameda, Walnut Creek, Livermore, Berkeley, Castro Valley, Fremont, Alamo, Hayward.
EMSC reported a loud jolt with rolling waves in California at San Ramon, Blackhawk, Dublin, Castro Valley and Firview in the Hayward Hills.
O: 02JAN2026 00:58:59 37.8N 122.0W ML=3.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 02JAN2026 07:13:46 37.3N 121.7W MD=2.2 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.6 near Adak, Alaska was probably felt with intensity up to II-III in the area.
This earthquake occurred within minutes of local solar noon and may have been
promoted by tidal and/or geomagnetic effects which maximize near this hour.
This epicenter is at the seventh node (52 degrees) from Taiwan, and the third node (120 degrees)
from the South Geomagnetic Pole. It is also at the 10th node (36 degrees) from the
North Geomagneti Pole and near the fourth node (90 degrees) from Tropical Cyclone Iggy
and may have been promoted by energy from those sources.
O: 02JAN2026 00:17:46 51.4N 176.5W ML=3.7 EMSC ANDREANOF ISLANDS, ALEUTIAN IS
NEIC reported an earthquake of M 4.4 in Bio-Bio Chile was felt with intensity up to II-III in the area(s) of Bio-Bio Chile at Los Angeles.
EMSC reported moderate shaking in Cabrero and Los Angeles, Chile.
This epicenter is at the third node from Cyclone Grant and may have been
promoted by energy from that source.
O: 01JAN2026 13:25:41 37.2S 72.7W MB=4.4 EMSC BIO-BIO, CHILE
NEIC reported an earthquake of M 4.9 in Myanmar was felt with intensity up to II-III in the area(s) of Myanmar with III in Kyaukse, Mandalay and II in Pakokku, Magway.
EMSC reported strong shaking in Myanmar at Shwebo, Mandalay, Sagaing, and Nyaungshwe.
This epicenter is at the ninth node (40 degrees) from Tropical Cyclones Iggy and Grant;
at the fourth node from the South Geomagnetic Pole and at the eighth node (45 degrees)
from Hokkaido and may have been promoted by energy from those sources.
O: 01JAN2026 13:19:00 22.8N 95.9E MB=4.9 EMSC MYANMAR
O: 01JAN2026 14:03:19 22.6N 96.2E ML=4.4 EMSC MYANMAR
NEIC reported an earthquake of M 4.6 in Zulia, Venezuela was felt with intensity up to II-III in the area(s) of Zulia, Venezuela in Maracaibo.
This event may have been promoted by antipodal energy focused from Tropical
Storm Iggy as noted in the previous issue of this summary:
"TC IGGY 2026-01-01 00:00 UT 13.0S 109.0E 55 kts North of western Australia
Tropical Cyclone Iggy (11S) formed today in the region of north of western Australia winds up to 55 kts in a non-seismic area. The antipode is at 14N 71W - is in the region north of Venezuela and could tigger a moderate seismic event near this location in the next several days." (January 1, 2026)
In addition to the antipode of TC Iggy this epicenter is at the third node from Hokkaido
and 143 degrees from Taiwan and 102 degrees from Kamchatka and may have
been promoted by energy from those sources.
O: 01JAN2026 12:37:04 10.4N 72.0W MB=4.6 EMSC ZULIA, VENEZUELA
P: 01JAN2026 178379 12.0N 72.0W 4.0-5.6 ABAAA Colombia
NEIC reported an earthquake of M 5.0 in Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Mindanao, Philippines with IV in Bislig, Caraga and in Canocotan, Southern Mindanao with III in Andili and II in Buayan, southern Mindanao and in Sibagat, Caraga.
EMSC reported moderate shaking in Mindanao at Mati, Magugpo Poblacion, Davao.
In addition to being at the fifth node (72 degrees) from the South Geomagnetic
pole, this epicenter is at the 12th node (30 degrees) from Tropical Cyclone Iggy
and at the seventh node (51 degrees) from Tropical Cyclone Grant and may have
been promoted by energy from those sources.
O: 01JAN2026 10:46:12 7.8N 126.8E MB=5.0 EMSC MINDANAO, PHILIPPINES
EMSC reported a series of light earthquake of M 3.0-3.5 in Czechia was felt with intensity up to IV in the area(s) of Czechia at Luby, Plesna, Olovi, Kraslice, Rotava, Habartov, Klingenthal, As, Brezova, Cheb, Vresova, Nejdek, Chodov, Karlovy Vary, Horni Slavkov, Otovice, and in Germany at Theuma, Pohl, Morgenrothe-Rautenkranz and Schneeberg.
This epicenter is at the fourth node from Tropical Cyclone Grant and at 105
degrees from TC Iggy and may have been promoted by energy from those sourcs.
O: 01JAN2026 17:04:52 50.3N 12.5E ML=3.4 EMSC CZECH REPUBLIC
O: 01JAN2026 16:38:25 50.3N 12.4E ML=3.3 EMSC CZECH REPUBLIC
EMSC reported an earthquake of M 3.2 in the Leeward Islands near Guadeloupe was felt with intensity up to IV in the area(s) of Guadeloupe.
This epicenter is at the position of the antipode of Tropical Cyclone Hayley
on December 30, 2025. It is likely it was promoted by antipodal focused
energy from that source as reported at the time in this summary:
"TC HAYLEY 2025-12-30 00:00 UT 16.5S 122.0E 110 kts North of western Australia
Tropical Cyclone Hayley (10S) continued today in the region north of western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 16N 58W - is in the area of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow." (December 30,, 2025)
This area of the Caribbean is active and a further moderate earthquake
could still occur near this epicenter in the next several days.
This epicenter is located at 144 degrees from TC Grant, the fifth node (72 degrees) from the Yukon, Canada; the third
node (120 degrees) from Hokkaido and at 103 degrees from Kamchatka and
may have been promoted by energy from those sources.
O: 02JAN2026 04:38:26 15.9N 60.9W ML=3.2 EMSC GUADELOUPE REGION, LEEWARD ISL
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE IGGY (11S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC IGGY 2026-01-02 00:00 UT 16.0S 108.5E 40 kts North of western Australia
Tropical Cyclone Iggy (11S) continued today in the region of north of western Australia winds up to 55 kts in a non-seismic area. The antipode is at 16N 71W - is in the region south of Haiti and Dominican Republic and could trigger a moderate seismic event near this location in the next several days.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2026-01-02 00:00 UT 15.0S 67.2E 55 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 55 kts north of Reunion and Mauritius. Increased volcanism in these islands is likely at TC Grant passes to the north in the next three days. The antipode is at 15N 113W - is south of The Gulf of California, Mexico where enhanced antipodal activity is possible.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of January 1, 2026. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6920 0056 0103 0108 C1.7 (January 1, 2026) 1.3E-03
Southern Greece M 3.5 00:56 UT
6930 0119 0124 0128 C1.8 (January 1, 2026) 1.0E-03
SE Indian Ridge M 6.0 01:53 UT
6960 0215 0225 0233 C9.6 (January 1, 2026) 6.7E-03
Hokkaido M 3.7 02:23 UT
Kamchatka M 4.4 02:13 UT
6990 0534 0537 0542 C2.0 (January 1, 2026) 1.1E-03
Kamchatka M 4.9 05:47 UT
Central California M 2.1 05:38 UT
7000 0552 0604 0609 C2.4 (January 1, 2026) 3.2E-03
Papua M 5.0 06:02 UT
7040 0609 0622 0629 C4.4 (January 1, 2026) 4.4E-03
Hindu Kush M 4.3 06:14 UT
7010 0642 0648 0651 C5.3 (January 1, 2026) 2.3E-03
Yukon M 5.3 06:55 UT
Yukon M 5.7 06:47 UT
7060 1504 1510 1515 C1.6 (January 1, 2026) 1.1E-03
Kamchatka M 4.8 15:17 UT
Panama M 3.8 15:17 UT
7070 1548 1555 1603 C2.1 (January 1, 2026) 1.9E-03
Hokkaido M 4.3 15:56 UT
Sucre, Venezuela M 3.7 16:11 UT
7080 1727 1759 1830 C6.2 (January 1, 2026) 1.5E-02
Ryukyu Is. M 3.7 17:32 UT
Nevada M 2.1 17:38 UT
7090 1846 1855 1905 C3.9 (January 1, 2026) 4.6E-03
Mindanao M 3.9 18:53 UT
Hawaii M 2.0 18:45 UT
7100 2143 2150 2155 C2.7 (January 1, 2026) 1.8E-03
Kermadec Islands M 3.9 21:46 UT
Guerrero M 3.9 22:09 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: major storms January 3, 2026 with minor storms January 2 and 4, 2026. Solar M-flare chance: 50% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 12 15 10 17:00 5 120 169
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
January 1, 2026
Notable earthquakes and events:
The full moon will arrive on January 3, 2026 at 10:03 UT. Longitudes which are at local solar noon at this time are localed near 27 East longitude while those at local solar midnight are near 154 West longitude. In the west these include Hawaii and areas of eastern and southern Alaska and to a lesser extent areas off the coast of Oregon and California and the east Pacific Rise while in the east they include Western Turkey and Greece and Romania as well as Ethiopia and areas off southern Africa and eastern Europe. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time. A large to major earthquake is considered moderately likely in the period January 1-8, 2026.
A strong M-class solar flare (#6870) occurred today. This flare - initially classified by SWPC - as an M7.1
is the strongest solar flare reported since an X1.9 (#230) on December 1, 2025
and an X1.1 on December 8, 2025 (#2960). Following are the flare parameters for this flare from SWPC.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6870 1312 1351 1445 M7.1 (December 31, 2025) 1.2E-01 *
BANDA Sea M 4.1 13:30 UT
Yap, Micronesia M 4.7 13:45 UT
Loyalty Is. M 5.0 13:51 UT
Northern Honshu, M 6.0 14:26 UT
*indicates modified reading from NOAA GOES Graph
At the time of the X1.1 flare on December 8, 2025 this summary noted:
"Today's earthquake (of M 7.6 in Hokkaido, Japan) occurred within minutes of local solar midnight, a time
when triggering of seismicity is most likely by tidal and geomagnetic effects
and this event may have been promoted by a strong X1.1 flare earlier in the day.
In the previous issue of this summary it had been noted that a strong X1.1
flare earlier in the day could result in this type and placement of a
strong earthquake later on December 8, 2025 as:
The most likely seismic enhancement with this flare would occur near 75 West
and 105 East longitudes including areas of western South America and eastern
Indonesia among others (including to the north along the western Pacific Rim). A moderate to strong quake is possible in these areas
before the end of the day." (December 8, 2025)
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0448 0510 0525 X1.1 (December 8, 2025) 1.1E-01 *
Myanmar M 3.8 04:49 UT
Yukon, Canada M 3.6 04:49 UT
Kuril Is. M 4.5 04:58 UT
" (December 8, 2025)
Similar triggered seismicity with the today's M7.1 solar flare could
be expected along the western Pacific rim (especially in Japan).
In Fact, toward the end of today's M7.1 flare, a strong earthquake did
occur - in Hokkaido, Japan with M 6.0 the the following parameters:
Readers should note the coincidence in timing with the M 7.6 of December 8, 2025
(within about 12 minutes of the same time of day) as recorded in this
summary:
O: 31DEC2025 14:26:56 40.1N 142.9E MW=6.0 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 08DEC2025 14:15:10 41.0N 143.1E MW=7.6 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 09NOV2025 08:03:38 39.5N 143.3E Mw=6.8 EMSC OFF EAST COAST OF HONSHU, JAPAN
This earthquake occurred within minutes of local solar midnight during the
M7.1 solar flare described above. NEIC reported it was felt with intensity
up to IV in Morioka, Iwate and lightly in Yokohama, Kanagawa, Japan.
This is the strongest earthquake within about 200 km of this epicenter since
the M 7.6 and M 6.6 on December 8, 2025 and an aftershock of M 6.7 on December 12, 2025.
Readers should note the coincidence in timing with the M 7.6 of December 8, 2025
(within about 12 minutes of the same time of day). Today's epicenter lies about 100 km south of those events and about 100 km north of the M 6.8 in
northern Honshu of November 9 and 10, 2025. The M 6.8 in northern Honshu
of that date (which began the current series of strong earthquakes in northern Japan) also occurred towards the end of a major solar flare - an X1.7
as reported in this summary and SWPC with parameters:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6870 1312 1351 1445 M7.1 (December 31, 2025) 1.2E-01 *
Northern Honshu, M 6.0 14:26 UT
4640 0654 0733 0843 X1.7 (November 9, 2025) 3.2E-01
Honshu M 6.8 08:03 UT
This M7.1 today was the strongest solar flare reported by SWPC before the X1.7 on
December 8, 2025.
The epicenter of M 6.0 in northern Honshu today was located at the seventh node from Yukon, Canada
and at the sixth node (60 degrees) from Tropical Cyclone Iggy.
All of these events (including today's M 6.0) are likely to have been promoted
and triggered by Solar Flare Effects (SFE) associated with major solar flares.
Moderate earthquakes near local solar midnight also occurred and were related
to the M7.1 solar flare in Micronesia (M 4.7) and the Loyalty Islands (M 5.0).
An earthquake of M 4.1 occurred in North Island, New Zealand today. GeoNet
reported the following parameters for this event:
O: 31DEC2025 12:09:41 40.2S 174.4E MB=4.1 GEONET Felt with moderate intensity in the area southeast of Levin, New Zealand and in southern North Island and northern South Island. 154 reports of felt events were made of which 96 reported weak and 55 light intensity with 3 reports of moderate shaking and 0 with strong and 0 severe and 0 with extreme intensity came from the area.
This eicenter is located at the fourth node from Tropical Cyclone Grant (90 degrees)
and at the sixth node from Tropical Cyclone Iggy and may have been promoted
by energy from those sources.
O: 31DEC2025 12:09:41 40.2S 174.4E ML=4.0 EMSC COOK STRAIT, NEW ZEALAND
The strongest earthquake in the U.S. or Canada today was an M 5.7 followed by an M 5.3 in southeastern Alaska.
NEIC reported it with felt with intensity III in Whitehorse and IV in Haines Junction, Yukon Territory, Canada and in Alaska with III in Yakjutat, Haines, Copper Center and lightly in Elfin Cove.
This is the strongest aftershock to date of the M 7.0 of December 6, 2025
in the Yukon Territory, Canada although a similar event of M 5.7-5.8 occurred on December 8, 2025. A series of increasingly large aftershocks has occurred in this area over the
past several days as reported in the previous issue of this summary:
"The strongest earthquake in the U.S. or Canada today was an M 5.1 in southeastern Alaska
along the border with Yukon Territory, Canada. NEIC reported this event
was felt with intensity III in Yukon, Canada at Whitehorse and Haines Junction with II.
It follows a slow increase in regional seismicity over the past two days
as reported in the previous issue of this summary:
"The strongest earthquakes in the U.S. or Canada today were a series about 200 km outside the
aftershock zone southeast of the M 7.0 in the Yukon, Canada event of December 6, 2025.
These events of M 3.5 and 3.6 follow an M 4.6 in the region yesterday. That event
is the strongest aftershock of the December 6 mainshock since an M 4.7 on December
10, 2025. Recent increases in solar activity may indicate activation of the
area with the possibility of a further event of M>=5 in the next couple of
days. Today's earthquakes were probably felt with intensity up to III in the Elfin Cove area of
Alaska as per NEIC data.
These epicenters are at the seventh node (52 degrees) from Hokkaido
and may have been promoted by energy from that source." (December 29-30, 2025)
Today's event of M 5.0 is located at 105 degrees from Tropical Cyclone Hayley
and may have been promoted by energy from that source as well as from Honshu, Japan." (December 31, 2025)
Today's epicenter of the M 5.7 is located at the fifth node (72 degrees) from
Taiwan and may have been promoted by energy from that source.
O: 01JAN2026 07:54:37 60.4N 140.2W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:46:53 60.5N 140.0W Mw=5.7 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:49:06 60.5N 140.0W ML=4.3 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:51:01 60.5N 140.1W mb=4.8 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:02:52 60.5N 139.9W ML=3.6 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:08:30 60.5N 140.1W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:11:42 60.5N 140.1W ML=3.4 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:17:01 60.5N 140.2W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:25:02 60.5N 139.9W ML=3.7 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:36:48 60.5N 139.9W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:52:35 60.5N 140.1W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 08:26:08 60.5N 140.2W ML=3.1 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 08:43:17 60.5N 140.0W ML=2.9 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 08:48:24 60.5N 140.1W ML=3.0 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:54:15 60.6N 140.0W ML=3.9 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:54:58 60.6N 140.1W Mw=5.3 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 06:57:50 60.6N 140.1W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:05:28 60.6N 140.2W ML=3.3 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 01JAN2026 07:10:13 60.6N 139.9W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 31DEC2025 23:04:29 51.3N 159.7E mb=4.6 EMSC OFF EAST COAST OF KAMCHATKA
O: 01JAN2026 00:03:05 60.4N 139.6W ML=3.4 EMSC SOUTHERN YUKON TERRITORY, CANA
P: 28DEC2025 178312 60.1N 139.4W 3.2-5.1 BAAAA Central Alaska
A moderate earthquake of M 5.3 also occurred today in the area of northern Argentina
near San Antonio de los Cobres. This earthquake occurred at an intermediate
depth of 182 km and was not reported felt at the surface. It occurred within
a couple of minutes of local solar midnight at a latitude which was nearly
sub-solar today (January 1, 2026) and may have been promoted by tidal and/or
geomagnetic stresses which maximize near this hour and latitude.
This epicenter is located at 143 degrees from Tropical Cyclone Iggy and at
103 degrees from the Yukon, Canada and may have been promoted by energy
from those sources. It is also nearly antipodal to Taiwan.
O: 01JAN2026 04:26:24 24.2S 66.8W MW=5.3 EMSC SALTA, ARGENTINA
Another earthquake of interest today was an M 5.4 in the Banda Sea, Indonesia.
NEIC reported it was probably felt with intensity up to III in the epicentral
This event occurred several minutes of local solar noon and was probably promoted
by tidal and/or geomagnetic stresses which maximize near this hour and latitude.
This epicenter is near the 12th node from Taiwan and the sixth node from
Cyclone Grant and may have been promoted by energy from those sourcs.
O: 01JAN2026 03:05:26 6.5S 129.9E MB=5.4 EMSC BANDA SEA
NEIC reported an earthquake of M 6.0 in the Southeast Indian Ridge was not felt in this
remote epicentral area. It occurred in late solar morning in this epicentral area (January 1, 2026). This is the strongest earthquake within about 300 km
of this epicenter in the Indian Ridge since an M 6.3 on March 24, 2018 and priot to that an M 6.4 on
November 10, 2010. At the time this summary noted:
"An earthquake in the South Indian Ocean of M 6.2-6.3 was also well forecast to occur
at this time. This is a remote area and this event was not reported felt. It
occurred near local solar midnight and tidal stresses may have helped promote
this event as did geomagnetic effects at this high latitude. The last earthquake
within about 200 km of this epicenter with M>=6.3 was an M 6.5 on November 10, 2010. Other quakes hit the
region with M 6.3-6.5 on October 29, 2005 and February 18, 1994. The antipode
of this event is in southern Ontario, Canada near Ohio at 45N 84W. A light
sympathetic quake could occur near this epicenter in the next several days." (March 24, 2018)
Today's epicenter in the Southeast Indian Rise is at the fifth node (72 degrees)
from Taiwan; the sixth node (60 degrees) from Mindanao and the 10th node (36 degrees)
from Tropical Cyclones Iggy and Grant in addition to 144 degrees from Yukon, Canada and may have been promoted by
enery from those sources.
O: 01JAN2026 01:53:01 45.6S 96.4E MW=6.0 EMSC SOUTHEAST INDIAN RIDGE
NEIC reported an earthquake of M 4.0 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Kenai, Anchorage, Soldotna.
O: 31DEC2025 20:36:18 60.0N 152.9W ML=4.0 EMSC SOUTHERN ALASKA
EMSC reported an earthquake of M 4.1 in Mindanao, Philippines was felt with intensity up to IV in the area(s) of Mindanao, Philippines in General Luna.
O: 31DEC2025 16:56:52 9.7N 126.2E ML=4.1 EMSC MINDANAO, PHILIPPINES
EMSC reported an earthquake of M 4.0 in Antofagasta, Chile was felt with intensity up to IV in the area(s) of Antofagasta, Chile.
O: 31DEC2025 12:37:41 23.9S 70.6W ML=4.0 EMSC OFFSHORE ANTOFAGASTA, CHILE
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE IGGY (11S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC IGGY 2026-01-01 00:00 UT 13.0S 109.0E 55 kts North of western Australia
Tropical Cyclone Iggy (11S) formed today in the region of north of western Australia winds up to 55 kts in a non-seismic area. The antipode is at 14N 71W - is in the region north of Venezuela and could tigger a moderate seismic event near this location in the next several days.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2026-01-01 00:00 UT 16.0S 68.2E 65 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 65 kts as a Strong storm. The antipode is at 16N 112W - is south of The Gulf of California, Mexico where enhanced antipodal activity is possible.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 31, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6750 0023 0027 0030 C1.8 (December 31, 2025) 8.5E-04
Kuril Is. M 4.4 00:27 UT
Cebu Philippines M 3.8 00:28 UT
6760 0123 0132 0135 C5.9 (December 31, 2025) 2.5E-03
6780 0626 0635 0648 C2.1 (December 31, 2025) 2.7E-03
New Zealand M 3.1 06:40 UT
Sumatra M 3.8 06:28 UT
6800 0942 0952 1003 C3.6 (December 31, 2025) 4.1E-03
New Zealand M 3.2 09:45 UT
6830 1003 1012 1016 C3.8 (December 31, 2025) 3.0E-03
6850 1237 1244 1254 C1.9 (December 31, 2025) 1.9E-03
Antofagasta M 4.0 12:37 UT
6870 1312 1351 1445 M7.1 (December 31, 2025) 1.2E-01
BANDA Sea M 4.1 13:30 UT
Yap, Micronesia M 4.7 13:45 UT
Loyalty Is. M 5.0 13:51 UT
Northern Honshu, M 6.0 14:26 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: major storms January 3, 2026 with minor storms January 1-2, 2026. Solar M-flare chance: 55% X-class: 20% proton storm: 40%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 7 17 7 17:00 6 127 171
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
December 31, 2025
Notable earthquakes and events:
A moderate earthquake of M 5.0 was widely felt today in the region of
Northern California near Susanville near local solar midnight. NEIC reported it was felt with intensity
up to VII in the epicentral area with reported intensities to NEIC of V in
California at Susanville; III in Fort Bidwell, Twain Harte, Old Station, Crescent Mills, Sierraville, Janesville, McCloud, Taylorsville, milford, Chilcoot, Kings Beach, Cedarville, Camptonville, Chester, Greenville, Canyon Dam, Quincy, McArthur, Meadow Vista, Alta, Doyle,Olympic Valley, Sparks, Grass Valley, and in Nevada at Reno, Sparks, among others within about 150 km of the epicenter.
EMSC reported strong shaking in northern California at Hamilton Branch, Magalia, Cedarville, Chico, Redding, San Francisco and in Nevada at North Valleys, Lemon Valley, Reno, Sparks.
At M 5.0 this is the strongest earthquake in northern California within
about 200 km of this epicenter since an M 5.5 and M 5.2 southeast of this epicenter
on May 11 and 12, 2023.
Today's event is part of a series that began with an M 4.7 on December 29 and is the largest in that
series. It followed four days after the M 7.0 in Taiwan of December 27
and had been expected in this summary at the time as:
"The lull in seismicity in the region of northern California came to an
end today. This began when an M 2.4 occurred in the San Francisco Bay,
California occurred at 15:16 UT but continued with an M 2.8 and M 2.3
within minutes of local solar noon, again in the San Francisco Bay area.
But the main event in the series was an M 4.7 northeast of San Francisco.
These earthquakes were associated with a series of moderate C- to moderate
M-class solar flares. For example the M 2.8 in San Francisco occurred
especially the local noon time events of 19:56 UT. The M 4.7 in northern
California occurred at the end of solar flare 6400. These flares probably
promoted the occurrence of these event in northern California today.
...
The area had been under a moderate seismic watch (in the previous issue of
this summary) due to historical analysis of regional seismicity following
large earthquakes in Taiwan as:
"The series of earthquakes in the San Francisco Bay area of California on the
northern Calaveras fault appears to have come to a temporary halt following
the earthquake in Taiwan. The distance between these two areas is 96 degrees
and is not nodal. There has been a tendency for larger quakes of M>=4.5 to
occur about 5 days after major events in Taiwan. This occurred in 1906 when
an M 7.2 in Taiwan was followed by the M 8.1 in San Francisco on April 18, 1906.
Earthquake of M>=5.0 in the San Francisco Bay area also occurred in the first 10 days after major
events in Taiwan in March, and January, 1986; September, 1935; August, 1989.
If this lull in Central California is precursory a moderate quake may
occur in this area in the next 5-10 days. A moderate watch for the area
is now in effect through January 7, 2026. Southern California and Baja California
are closer to 103 degrees from Taiwan. Even so, there is scant evidence
in the historical record that these areas are likely to see enhanced
seismicity at this time. A pair of quakes in the Los Angeles area of 2.7 and M 2.5
preceded the Taiwan quake by about 30 minutes today. A similar M 4.5
in Los Angeles followed an M 6.6 in Taiwan at the same location as today's
event a day later on May 24-25, 1994. The only other activity on record
of M>=4.5 associated with major earthquakes in Taiwan occurred in April, 1910
and September 4, 1935. This area is not under watch from the Taiwan earthquake at this time." (December 27-28, 2025)
The earthquake of M 4.7 in Northern California today was widely felt north
of Sacramento with V in California at Litchfield; IV in Susanville, Milford, Ravendale, Tahoe City, Standish, Janesville and III in Wendel and Cedarville.
The last earthquake in northern California within about 200 km of today's
epicenter with M>=4.7 occurred as an M 5.0 about 100 km northwest of this on September 8, 2023.
The last earthquake within about 100 km of this epicenter of larger magnitude
was an M 5.5 on May 11, 2023 (and an M 5.2 aftershock hours later). At the time this summary noted:
"The largest earthquake in the U.S. or Canada today was an M 5.0 in northern California.
NEIC reported it was felt with intensity V in Northern California near Cassel, Burney, Fall River Mills, McArthur, IV in Montgomery Creek, Old STation, Whitmore, Oak Run, McCloud, and with lesser intensity in Southern California and Oregon.
An aftershock of M 4.3 was reported with intensity V in McArthur, IV in Redding; III in Milford and I in Santa Rosa, California.
This activity occurred near local solar noon and may have been promoted by
tidal stresses which maximize near this hour. The last earthquake in Northern
California of M>=5 within about 100 km of today's epicenter occurred more than
35 years ago. An M 5.5 and 5.2 occurred about 100 km southeast of today's epicenter
on May 11 and 12, 2023. Other regional seismicity at about 100 km from
today's epicenter occurred with M 5.7 about 100 km to the southeast on May 24, 2013
and as an M 5.4 on November 26, 1998." (September 8, 2023)
Today's epicenter in northern California is located near the fourth node (90 degrees)
from Taiwan; at 144 degrees from a much-strengthened TC Grant; the third node
(120 degrees) from newly formed TC Hayley; and 103 degrees from Mindanao, Philippines and the seventh node (52 degrees) from Kamchatka and the north geomagnetic pole and
may have been promoted by energy from those sources." (December 29, 2025)
O: 29DEC2025 00:41:14 40.5N 120.7W MW=4.7 EMSC NORTHERN CALIFORNIA
An earthquake of M 3.7-4.6 occurred today in the Tennant Creek area of northern
Australia. It was probably felt lightly in the epicentral area.
The last earthquake of M>=4.6 within about 300 km of this epicenter in Australia
was an M 5.4 on August 1, 2019. At the time this summary noted:
"A moderate earthquake of M 5.4 hit the northern Territory, Australia today.
NEIC reported this earthquake of M 5.4 in Northern Territory, Australia was felt with intensity II-III in the area(s) of Tennant Creek, Northern Territory, Australia.
This continues activity which has included an M 6.6 off western Australia in
mid-July. This is the strongest earthquake in the Tennant Creek area of northern
Territory in at least 30 years. This earthquake is located at 105 degrees from the
M 7.1 in Central California of July 6 and was probably promoted by energy from that source.
The antipode is in the northern Mid-Atlantic at 20N 45W where a possible event could occur." (August 1, 2019)
and earlier when an M 4.4 occurred on March 12, 2021 as:
"An unusual earthquake also hit off the east coast of northeastern Australia today.
NEIC reported this earthquake of M 4.4 in Northern Territory, Australia was felt with intensity II-III in the area(s) of Northern Territory, Australia at Tennant Creek.
It also occurred near local solar midnight and was probably promoted by
strong tidal stresses which maximize near this hour. Powerful Tropical Cyclone
Niran passed near this epicenter in early March and may have helped promote
seismicity near this epicenter. Stronger earthquakes within about 200 km
of today's epicenter in the past 30 years occurred on February 11, 2004 (M 4.9, 5.0)
and July 15, 1992 (M 5.2) and June 13, 1992 (M 5.0)." (March 12, 2021).
Today's event in northern Australia occurred as Tropical Cyclone Hayley was approaching this epicenter
as previously reported in this summary.
"Tropical Cyclone Hayley (10S) continued today in the region north of western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 16N 58W - is in the area of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow." (December 29-30, 2025)
The current parameters for TC Hayley are:
TC HAYLEY 2025-12-31 00:00 UT 20.5S 132.0E 110 kts Northern Australia
Tropical Cyclone Hayley (10S) continued today in the region of northern and western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 20N 48W - is in the area east of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow in northern Australia.
This earthquake in northern Australia occurred within minutes of local solar noon
at a latitude which was nearly sub-solar today (December 30, 2025 21 degrees South
Latitude). This means this epicenter was at sub-solar conditions at the time
of this earthquake, conditions which have been linked to enhanced seismicity
as reported in previous issues of this summary.
This epicenter is located at 2-3 degrees from the current eye of Tropical Cyclone
Hayley; at 105 degrees from the North Geomagnetic Pole and Yukon, Canada; at the sixth node (60 degrees)
from Honshu and at the eighth node (45 degrees) from Taiwan and may have been
promoted by constructive interference of energy associated with those sources.
O: 31DEC2025 03:35:57 20.5S 134.4E ML=3.7 EMSC NORTHERN TERRITORY, AUSTRALIA
O: 31DEC2025 03:35:57 20.5S 134.4E ML=4.6 NEIC TENNANT CREEK, AUSTRALIA
The strongest earthquake in the world today was an M 5.3 near Boyuibe, Bolivia.
It was not reported felt in this epicentral area as it occurred at a deep focal depth (547 km).
Like the earthquake in northern Australia (see above) this epicenter is at
a latitude which is sub-solar on this day of the year while near local solar noon and may been promoted
by efficient tidal and/or geomagnetic stresses at this time.
This event is near the antipode of the M 7.1 in Taiwan of December 27, 2025
and may have been promoted by antipodal focused energy from that source.
A deep focus M 5.6 south of this preceded the Taiwan earthquake and was noted in
this summary as:
"Today's earthquake in Taiwan occurred near the antipode of an M 5.6 earthquake at a
deep focus in Argentins earlier in the day and may have been promoted
by energy from that source. Despite the near-antipodal nature of these two
earthquake historical evidence does not support antipodal triggering in this case." (December 27, 2025)
The last earthquake within about 300 km of this epicenter in Bolivia with M>=5.3
occurred on April 2, 2018 with M 6.8. At the time this summary noted:
T"he earthquake in Bolivia had its hypocenter at a deep focus of 500-600 km. As such
it was widely felt with moderate to light intensity through a wide swath of
northern South America up to 1900 km from the epicenter but no damage was reported.
NEIC noted intensity up to V in Asuncion, Paraguay but generally intensities were
II-III. These were reported from Bolivia, Chile, Paraguay, Peru, Brazil, and Argentina.
CSN reported this earthquake was felt with intensity V Chile in Huara; III Cuya, Camina, La Tirana, Tocopilla, II Arica, Alto Hospicio, Iquique, Maria Elena, Felt in Arica, Parinacota, Tarapaca and Antofagasta, Chile.
The mainshock was followed by an M 3.7 in the area of Peru where it was reported
felt in Arequipa with intensity III. The last earthquake in Bolivia within
about 300 km of this epicenter with M>=6.8 occurred more than 45 years ago.
Two quakes have been recorded in this area in recent history, an M 6.8 on October 25, 1973
and events of M 6.9 and 7.0 on September 23, 1887 and March 23, 1899." (April 2, 2018)
This epicenter is located at 174 degrees (near antipodal) from Taiwan and at 102 degrees
from Yukon, Canada and may have been promoted by energy from those sources.
O: 30DEC2025 20:26:05 20.7S 63.2W MW=5.3 EMSC CHUQUISACA, BOLIVIA
The strongest earthquake in the U.S. or Canada today was an M 5.1 in southeastern Alaska
along the border with Yukon Territory, Canada. NEIC reported this event
was felt with intensity III in Yukon, Canada at Whitehorse and Haines Junction with II.
It follows a slow increase in regional seismicity over the past two days
as reported in the previous issue of this summary:
"The strongest earthquakes in the U.S. or Canada today were a series about 200 km outside the
aftershock zone southeast of the M 7.0 in the Yukon, Canada event of December 6, 2025.
These events of M 3.5 and 3.6 follow an M 4.6 in the region yesterday. That event
is the strongest aftershock of the December 6 mainshock since an M 4.7 on December
10, 2025. Recent increases in solar activity may indicate activation of the
area with the possibility of a further event of M>=5 in the next couple of
days. Today's earthquakes were probably felt with intensity up to III in the Elfin Cove area of
Alaska as per NEIC data.
These epicenters are at the seventh node (52 degrees) from Hokkaido
and may have been promoted by energy from that source." (December 29-30, 2025)
Today's event of M 5.0 is located at 105 degrees from Tropical Cyclone Hayley
and may have been promoted by energy from that source as well as from Honshu, Japan.
O: 30DEC2025 10:17:19 60.4N 139.6W MW=5.0 EMSC SOUTHERN YUKON TERRITORY, CANA
O: 30DEC2025 11:05:26 60.4N 139.5W ML=3.2 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 30DEC2025 12:31:03 60.5N 139.9W ML=3.4 EMSC SOUTHERN YUKON TERRITORY, CANADA
O: 30DEC2025 22:25:44 60.5N 140.0W ML=3.5 EMSC SOUTHERN YUKON TERRITORY, CANADA
NEIC reported an earthquake of M 3.5 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Homer.
EMSC reported an earthquake of M 4.3 in Syria was felt with intensity up to IV in the area(s) of Syria in Latakia, 'Ayn al Bayda, Manbij, and in Pegeia, Paphos, Cyprus.
This epicenter is located at the fifth node (72 degrees) from Taiwan and at 104
degrees from Tropical Cyclone Hayley and may have been promoted by energy from
those sources.
O: 30DEC2025 15:05:32 35.6N 35.4E MB=4.3 EMSC NEAR THE COAST OF SYRIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE HAYLEY (10S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC HAYLEY 2025-12-31 00:00 UT 20.5S 132.0E 110 kts Northern Australia
Tropical Cyclone Hayley (10S) continued today in the region of northern and western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 20N 48W - is in the northern mid-Atlantic Ridge where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow in northern Australia.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-31 00:00 UT 15.0S 73.1E 130 kts South Indian Ocean
Tropical Cyclone Grant (09S) continued today in the region of the south Indian Ocean winds up to 130 kts as a suddenly forming major storm. The antipode is at 15N 107W - is southeast of Jalisco, Mexico where enhanced antipodal activity is possible.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 30, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6630 0014 0027 0033 C4.9 (December 30, 2025) 4.1E-03
6650 0058 0103 0105 C2.9 (December 30, 2025) 1.4E-03
6660 0638 0645 0647 C5.0 (December 30, 2025) 2.9E-03
Colima, Mexico M 3.2 06:38 UT
6670 0836 0843 0849 C4.6 (December 30, 2025) 3.6E-03
Nevada M 2.4 08:40 UT
Oaxaca M 4.1 08:42 UT
Ryukyu Is. M .1 08:48 UT
6690 1416 1423 1432 C2.2 (December 30, 2025) 2.2E-03
Kuril Is M 4.3 14:29 UT
6710 1551 1555 1600 C4.9 (December 30, 2025) 2.4E-03
6720 1742 1803 1816 C4.1 (December 30, 2025) 6.7E-03
6730 2243 2248 2253 C2.2 (December 30, 2025) 1.4E-03
6740 2336 2340 2342 C2.8 (December 30, 2025) 1.1E-03
Honshu M 4.8 23:51 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 31, 2025 and January 2, 2026 with minor storms January 1, 2026. Solar M-flare chance: 60% X-class: 25% proton storm: 15%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 8 13 5 15:00 4 141 182
A very strong Gamma Ray Burst was recorded by SWIFT on December 30, 2025 at 01:21:41 UT (#251230A). A preliminary UVOT Magnitude of V>14.67 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
December 30, 2025
Notable earthquakes and events:
It was another quiet day in global seismicity since last report. The only earthquake
in the world of M>5.1 was an M 5.5 in the Ryukyu Islands of Japan. This is about 500 km northeast
of the M 6.6-7.0 Taiwan earthquake of December 27 and may have been promoted by regional stress redistribution
following that event. NEIC reported it was felt in the Ryukyu Islands in Okinawa at Naha, and III in Ishikawa, Okinawa, Yomitan and II in Tomigusuku with III also reported in Naze, Kagoshima.
No damage, tsunami nor casualties were expected with this remote quake.
The last earthquake in the Ryukyu Islands within about 200 km of this
epicenter with M>=5.5 occurred as an M 5.9 on May 1, 2023 and before that
on December 13, 2022 with M 5.7. At the time this summary noted:
"A moderately strong M 5.9 earthquake in the Ryukyu Islands, Japan occurred today
after a series of moderate foreshocks including those of M 5.3, 5.2 and 5.0. The
foreshocks began with an M 5.3 on April 27 and continued through April 29, 2023. Today's event was reported by NEIC to have
been felt with intensity II-II in Okinawa at Gushikawa, Okinawa, Chatan, Irasoe, Naha and Yomitan.
The last earthquake of M>=5.9 in the Okinawa area of the Ryukyu Islands within
about 200 km of today's epicenter was an M 6.0 on July 26, 2017 and also on September 26, 2016." (May 1, 2023)
Today's epicenter is at the fourth node (90 degrees) from the South Geomagnetic Pole
and at the sixth node (60 degrees)from the North Geomagnetic Pole and the eighth
node (45 degrees) from Tropical Cyclone Hayley and may have been promoted by energy
from these sources.
O: 30DEC2025 08:12:24 27.5N 128.7E MW=5.5 EMSC RYUKYU ISLANDS, JAPAN
The strongest earthquakes in the U.S. or Canada today were a series about 200 km outside the
aftershock zone southeast of the M 7.0 in the Yukon, Canada event of December 6, 2025.
These events of M 3.5 and 3.6 follow an M 4.6 in the region yesterday. That event
is the strongest aftershock of the December 6 mainshock since an M 4.7 on December
10, 2025. Recent increases in solar activity may indicate activation of the
area with the possibility of a further event of M>=5 in the next couple of
days. Today's earthquakes were probably felt with intensity up to III in the Elfin Cove area of
Alaska as per NEIC data.
These epicenters are at the seventh node (52 degrees) from Hokkaido
and may have been promoted by energy from that source.
O: 28DEC2025 18:50:49 60.5N 139.8W MB=4.6 EMSC SOUTHERN YUKON TERRITORY, CANA
O: 30DEC2025 06:00:34 58.3N 136.8W ML=3.5 EMSC SOUTHEASTERN ALASKA
O: 30DEC2025 03:33:25 58.4N 137.3W ML=3.2 EMSC SOUTHEASTERN ALASKA
O: 29DEC2025 08:05:17 59.5N 136.8W ML=3.2 EMSC SOUTHEASTERN ALASKA
O: 30DEC2025 05:23:46 58.3N 136.9W ML=3.6 EMSC SOUTHEASTERN ALASKA
NEIC reported an earthquake of M 2.5 in eastern Los Angeles, California was felt with intensity up to II-III in the area(s) of eastern Los Angeles, California in Lake Arrowhead and Big Bear City.
O: 30DEC2025 05:23:50 34.0N 116.8W ML=2.1 EMSC SOUTHERN CALIFORNIA
O: 29DEC2025 13:26:11 34.3N 117.1W ML=2.5 EMSC SOUTHERN CALIFORNIA
An earthquake of M 2.3 was also felt today in Los Angeles California. EMSC reported strong shaking in California at Ladera Heights, Culver City, Marina del Rey, View Park-Windsor Hills, Century City, North Hollywood.
NEIC reported it was felt widely in Los Angeles with intensity III in Inglewood, Los Angeles, Playa del Rey, Culver City, Venice, El Segundo, and II in Santa Monica, Aliso Viejo.
O: 29DEC2025 15:57:32 34.0N 118.4W ML=2.3 EMSC GREATER LOS ANGELES AREA, CALI
The most unusual earthquake today was an M 4.6 in the area of Ikungi, Tanzania.
It was not reported felt in this area near Dodoma. This earthquake occurred
within minutes of local solar noon near the peak of one of the largest
solar flares of the day (#6490) and may have been promoted by energy from that
flare. Data for that flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6490 0943 0947 0952 C3.8 (December 29, 2025) 1.8E-03
Tanzania M 4.6 09:51 UT
The last earthquake of M>=4.6 in Tanzania within about 200 km of today's
epicenter occurred as an M 4.8 on August 8, 2025. The last of significantly
larger magnitude in the area was an M 5.5 on August 8, 2023. At the time
this summary noted:
"The most unusual earthquake in the world today was an M 5.5 in Tanzania. NEIC reported this event was felt with intensity IV in Mombasa, Kenya and in Tanzania at Dodoma and Tabora.
An M 4.8 aftershock was felt with intensity II in Magugu, Manyara, Tanzania.
A foreshock of M 4.5 occurred on August 2, 2023 about 100 km north of today's
epicenter. The last earthquake of M>=5.5 in the region of Tanzania within about 300 km
of this epicenter occurred on November 4, 2002, the only such event in this
region in the past 35 years. Three days ago an M 4.9 hit the Lake Tanganyika area west of today's epicenter.
At the time this summary noted:
"An unusual quake of M 4.9 occurred today in the region of Tanzania. NEIC reported maximum intensity IV in Gitega, Burundi and Kigali Ville de Kigali, Rwanda and III in Kigoma, Tanzania at Kigoma and Kasulu.
The only earthquake of M>4.9 in Tanzania or Lake Tanganyika areas within about
250 km of this epicenter occurred with M 5.0 about 250 km northwest of today's
epicenter. Today's event occurred within minutes of local solar midnight
and may have been promoted by high tidal stresses which maximize near this
hour." (August 4, 2023, August 8, 2023)
This epicenter is located at the fourth node (90 degrees) from the South Geomagnetic
Pole and also from Taiwan and Mindanao and was probably promoted by
constructive interference of energy from those sources.
O: 29DEC2025 09:51:42 5.3S 35.3E MB=4.6 EMSC TANZANIA
EMSC reported an earthquake of M 4.0 in Costa Rica was felt with intensity up to IV in the area(s) of Costa Rica in Quepos where it woke residents.
O: 30DEC2025 03:14:30 9.4N 84.3W ML=4.0 EMSC COSTA RICA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE HAYLEY (10S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC HAYLEY 2025-12-30 00:00 UT 16.5S 122.0E 110 kts North of western Australia
Tropical Cyclone Hayley (10S) continued today in the region north of western Australia winds up to 110 kts. It could continue to promote enhanced seismicity in this area. The antipode is at 16N 58W - is in the area of the Leeward Islands where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-30 00:00 UT 14.3S 78.3E 135 kts South of India
Tropical Cyclone Grant (09S) continued today in the region south of India winds up to 135 kts as a suddenly forming major storm. The antipode is at 15N 102W - is east of Central America and south of Guerrero, Mexico where enhanced antipodal activity is possible.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 29, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6420 0119 0128 0132 C4.8 (December 29, 2025) 2.7E-03
6430 0258 0305 0310 C8.9 (December 29, 2025) 4.1E-03
Coast No. California M 3.3 03:01 UT
6450 0634 0651 0656 M1.0 (December 29, 2025) 7.6E-03
Western Mediterranean Sea M 3.6 06:39 UT
Nicaragua M 3.6 06:33 UT
6460 0723 0731 0736 C2.6 (December 29, 2025) 2.1E-03
Chiapas M 4.1 07:28 UT
6470 0757 0803 0807 C2.6 (December 29, 2025) 2.4E-03
6480 0807 0817 0828 C4.3 (December 29, 2025) 4.7E-03
Guerrero M 3.4 08:08 UT
6490 0943 0947 0952 C3.8 (December 29, 2025) 1.8E-03
Tanzania M 4.6 09:51 UT
6500 1210 1219 1224 C2.7 (December 29, 2025) 2.1E-03
6510 1310 1314 1318 C3.0 (December 29, 2025) 1.5E-03
Myanmar M 3.1 13:10 UT
6560 1630 1635 1642 C3.3 (December 29, 2025) 2.5E-03
Mid-Indian Ridge M 4.9 16:39 UT
6570 1803 1811 1816 C3.5 (December 29, 2025) 3.1E-03
6600 1816 1827 1832 C3.3 (December 29, 2025) 3.4E-03
San Francisco M 2.2 18:32 UT
6590 2036 2040 2043 C6.4 (December 29, 2025) 2.8E-03
Guerrero M 3.5 20:35 UT
N Island, New Zealand M 3.5 20:36 UT
Sumatra M 2.6 20:36 UT
Halmahera M 3.7 20:41 UT
6610 2214 2222 2226 C3.3 (December 29, 2025) 2.9E-03
Guerrero M 3.5 22:22 UT
6640 2226 2230 2237 C3.7 (December 29, 2025) 2.8E-03
Kuril Is. M 4.5 22:47 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled December 30, 2025 active December 31 with minor storms January 1, 2026. Solar M-flare chance: 55% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 9 15 9 13:00 5 138 196
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
December 29, 2025
Notable earthquakes and events:
It was a relatively quiet day in global seismicity with no events of M>5
recorded. The lull in seismicity in the region of northern California came to an
end today. This began when an M 2.4 occurred in the San Francisco Bay,
California occurred at 15:16 UT but continued with an M 2.8 and M 2.3
within minutes of local solar noon, again in the San Francisco Bay area.
But the main event in the series was an M 4.7 northeast of San Francisco.
These earthquakes were associated with a series of moderate C- to moderate
M-class solar flares. For example the M 2.8 in San Francisco occurred
especially the local noon time events of 19:56 UT. The M 4.7 in northern
California occurred at the end of solar flare 6400. These flares probably
promoted the occurrence of these event in northern California today.
Data from SWPC for these flares follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6340 1502 1509 1516 C2.9 (December 28, 2025) 2.4E-03
San Francisco M 2.4 15:16 UT
6350 1917 2008 2040 C4.0 (December 28, 2025) 1.6E-02
San Francisco M 2.2 20:50 M 2.8 19:56 M 2.3 20:05 UT
6400 2357 0002 0007 M2.2 (December 28, 2025) 9.7E-03
Northern California M 4.7 00:41 UT
Nicaragua M 3.1 00:02 UT
The area had been under a moderate seismic watch (in the previous issue of
this summary) due to historical analysis of regional seismicity following
large earthquakes in Taiwan as:
"The series of earthquakes in the San Francisco Bay area of California on the
northern Calaveras fault appears to have come to a temporary halt following
the earthquake in Taiwan. The distance between these two areas is 96 degrees
and is not nodal. There has been a tendency for larger quakes of M>=4.5 to
occur about 5 days after major events in Taiwan. This occurred in 1906 when
an M 7.2 in Taiwan was followed by the M 8.1 in San Francisco on April 18, 1906.
Earthquake of M>=5.0 in the San Francisco Bay area also occurred in the first 10 days after major
events in Taiwan in March, and January, 1986; September, 1935; August, 1989.
If this lull in Central California is precursory a moderate quake may
occur in this area in the next 5-10 days. A moderate watch for the area
is now in effect through January 7, 2026. Southern California and Baja California
are closer to 103 degrees from Taiwan. Even so, there is scant evidence
in the historical record that these areas are likely to see enhanced
seismicity at this time. A pair of quakes in the Los Angeles area of 2.7 and M 2.5
preceded the Taiwan quake by about 30 minutes today. A similar M 4.5
in Los Angeles followed an M 6.6 in Taiwan at the same location as today's
event a day later on May 24-25, 1994. The only other activity on record
of M>=4.5 associated with major earthquakes in Taiwan occurred in April, 1910
and September 4, 1935. This area is not under watch from the Taiwan earthquake at this time." (December 27-28, 2025)
The earthquake of M 4.7 in Northern California today was widely felt north
of Sacramento with V in California at Litchfield; IV in Susanville, Milford, Ravendale, Tahoe City, Standish, Janesville and III in Wendel and Cedarville.
The last earthquake in northern California within about 200 km of today's
epicenter with M>=4.7 occurred as an M 5.0 about 100 km northwest of this on September 8, 2023.
The last earthquake within about 100 km of this epicenter of larger magnitude
was an M 5.5 on May 11, 2023 (and an M 5.2 aftershock hours later). At the time this summary noted:
"The largest earthquake in the U.S. or Canada today was an M 5.0 in northern California.
NEIC reported it was felt with intensity V in Northern California near Cassel, Burney, Fall River Mills, McArthur, IV in Montgomery Creek, Old STation, Whitmore, Oak Run, McCloud, and with lesser intensity in Southern California and Oregon.
An aftershock of M 4.3 was reported with intensity V in McArthur, IV in Redding; III in Milford and I in Santa Rosa, California.
This activity occurred near local solar noon and may have been promoted by
tidal stresses which maximize near this hour. The last earthquake in Northern
California of M>=5 within about 100 km of today's epicenter occurred more than
35 years ago. An M 5.5 and 5.2 occurred about 100 km southeast of today's epicenter
on May 11 and 12, 2023. Other regional seismicity at about 100 km from
today's epicenter occurred with M 5.7 about 100 km to the southeast on May 24, 2013
and as an M 5.4 on November 26, 1998." (September 8, 2023)
Today's epicenter in northern California is located near the fourth node (90 degrees)
from Taiwan; at 144 degrees from a much-strengthened TC Grant; the third node
(120 degrees) from newly formed TC Hayley; and 103 degrees from Mindanao, Philippines and the seventh node (52 degrees) from Kamchatka and the north geomagnetic pole and
may have been promoted by energy from those sources.
O: 29DEC2025 00:41:14 40.5N 120.7W MW=4.7 EMSC NORTHERN CALIFORNIA
O: 29DEC2025 00:48:27 40.5N 120.6W MD=2.3 EMSC NORTHERN CALIFORNIA
O: 29DEC2025 01:16:06 40.5N 120.7W MD=2.2 EMSC NORTHERN CALIFORNIA
O: 29DEC2025 06:08:48 40.5N 120.7W MD=2.3 EMSC NORTHERN CALIFORNIA
NEIC reported the earthquake of M 2.8 east of San Francisco was felt with intensity up to II-III in the area(s) of east of San Francisco with III in San Ramon and II in Walnut Creek, Danville and Pleasanton.
The earlier M 2.6 near San Ramon was reported by NEIC with intensity III in Danville, San Ramon and II in Pleasanton, San Francisco, Dublin.
These epicenters are at the third node (120 degrees) from Tropical Cyclone Hayley;
at 149 degrees from Tropical Cyclone Grant, the fifth node (72 degrees) from Hokkaido; the seventh node from Kamchatka and
Central Philippines and may have been promoted by energy from those sources.
O: 28DEC2025 13:18:58 37.8N 121.9W MD=2.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 28DEC2025 15:16:40 37.8N 121.9W MD=2.4 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 28DEC2025 19:56:43 37.8N 121.9W MD=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 28DEC2025 20:05:52 37.8N 121.9W MD=2.3 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 28DEC2025 20:50:21 37.8N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 29DEC2025 05:45:34 37.8N 122.0W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 29DEC2025 00:52:18 37.7N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
P: 27DEC2025 178181 37.7N 121.9W 2.5-4.8 AAAAA Central California
A series of light earthquakes occurred within minutes of each other today
near local solar noon in the eastern U.S. These occurred as an M 3.2 in
eastern Kentucky followed by an M 2.1 five minutes later near West Warrenton,
Georgia and preceded by an M 2.3 in Missouri on the New Madrid Fault line.
This event in Missouri was reported felt in southeastern Missouri at Stelle with intensity III
and with II in Missouri at Hornersville, Caruthersville, Sikeston, Clarkton and Dexter and in
Kentucky with II in Mayfield and Murray. NEIC reported these earthquakes near local
solar noon The M 4.2 in Kentucky was felt with intensity up to II-III in the area(s) of Kentucky with III in Lancaster, Paint Lick, Nicholasville, Wellington, Richmond, Stanford, Berea, Danville, and Crab Orchard and in Indiana at Madison.
This earthquake occurred within minutes of local solar noon and may have
been promoted by tidal and/or geomagnetic effects.
These epicenters are near 144 degrees from the south geomagnetic pole and Tropical Cyclones Grant and Hayley
and at the fourth node from Honshu, Japan and at the fifth node from Kamchatka
and may have been promoted by energy from those sources.
The event in Georgia is at the sixth node (60 degrees) from the north geomagnetic
pole and near the third node (120 degrees) from Taiwan and an the eighth node
(45 degrees) from Yukon, Canada and may have been promoted by energy from
those sources.
The epicenter in Missouri is also at the fourth node (90 degrees) from Hokkaido;
the fifth node from Kamchatka and may have been promoted by energy from those
sources.
O: 28DEC2025 17:47:10 37.7N 84.4W ML=3.2 EMSC EASTERN KENTUCKY
O: 28DEC2025 17:52:08 33.3N 82.7W ML=2.1 EMSC GEORGIA
O: 28DEC2025 17:10:08 36.1N 89.7W ML=2.3 EMSC MISSOURI
NEIC reported an earthquake of M 5.0 in Peru was felt with intensity up to II-III in the area(s) of Peru with IV in Chimbote, Ancash and II in Trujillo La Libertad.
This epicenter is located at 102-103 degrees from both the north and south
geomagnetic poles and near 146 degrees from Tropical Cyclones Grant and Hayley and
is an aftershock of the M 6.2 that hit the area yesterday. It may have been promoted by constructive interference from
energy associated with those sources.
O: 28DEC2025 23:19:55 9.0S 79.0W MB=5.0 EMSC NEAR COAST OF NORTHERN PERU
NEIC reported an earthquake of M 2.6 east of Los Angeles, California was felt with intensity up to II-III in the area(s) of east of Los Angeles, California with III in San Bernardino, II in Lake Arrowhead, Running Springs, Pomona, Cedar Glen, Highland, Crestline.
O: 28DEC2025 15:44:30 34.3N 117.1W ML=2.6 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.3 in Mammoth Lakes, California was felt with intensity up to II-III in the area(s) of Mammoth Lakes, California with II in Glenbrook, Nevada.
This epicenter is located at the fifth node from Hokkaido and 104 degrees
from Mindanao and may have been promoted by energy from those sources.
O: 28DEC2025 19:02:07 37.9N 118.7W ML=3.2 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.6 in Central Peru was felt with intensity up to II-III in the area(s) of Central Peru with II in Santa Maria, Lima and Vista Alegre, Ica.
This epicenter is at 145-146 degrees from Tropical Cyclones, Grant and Hayley; at the third node (120 degrees) from Kamchatka and at the fourth node (90 degrees) from Yukon, Canada and may have been promoted by energy from those sources.
O: 28DEC2025 13:09:38 13.5S 77.2W MB=4.6 EMSC OFF COAST OF CENTRAL PERU
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE HAYLEY (10S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC HAYLEY 2025-12-29 00:00 UT 15.7S 120.0E 90 kts North of western Australia
Tropical Cyclone 10S formed today in the region north of western Australia winds up to 45 kts. It could continue promote enhanced seismicity in this area. The antipode is at 12N 61W - is in the area north of Venezuela and Trinidad and Tobago where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-29 00:00 UT 13.7S 80.5E 145 kts South of India
Tropical Cyclone Grant (09S) continued today in the region south of India winds up to 145 kts as a suddenly forming major storm. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 93W - is east of Central America where enhanced antipodal activity is possible, but unlikely as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica off the west coast of Central America around December 27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 28, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6290 0535 0539 0557 C2.6 (December 28, 2025) 4.0E-03
6300 0557 0608 0610 C3.3 (December 28, 2025) 2.7E-03
6310 0722 0728 0735 C4.0 (December 28, 2025) 2.6E-03
6320 0809 0820 0834 C3.2 (December 28, 2025) 4.5E-03
Fiji M 4.5 08:16 UT
Kuril Is. M 4.3 08:11 UT
Fiji M 4.8 08:06 UT
6330 1157 1208 1221 C2.8 (December 28, 2025) 3.7E-03
6340 1502 1509 1516 C2.9 (December 28, 2025) 2.4E-03
San Francisco M 2.4 15:16 UT
6350 1917 2008 2040 C4.0 (December 28, 2025) 1.6E-02
San Francisco M 2.2 20:50 M 2.8 19:56 M 2.3 20:05 UT
6360 2103 2113 2123 M1.3 (December 28, 2025) 9.2E-03
6370 2148 2153 2156 C6.8 (December 28, 2025) 2.8E-03
6380 2201 2239 2254 M4.2 (December 28, 2025) 7.5E-02
Kyushu M 4.0 22:35 UT
6400 2357 0002 0007 M2.2 (December 28, 2025) 9.7E-03
Northern California M 4.7 00:41 UT
Nicaragua M 3.1 00:02 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet December 29-31. Solar M-flare chance: 45% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 9 13 7 13:00 4 143 188
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
December 28, 2025
Notable earthquakes and events:
A strong M 6.6-7.0 earthquake occurred today in Northern Taiwan. EMSC reported
very strong shaking in Taiwan in Yilan, Taipei, Banqiao, Taoyuan, Hualien City, Hsinchu, Zhubei, Taichung, Jiayi Shi, Ishigaki, Kaohsiung, and in China in Xiamen, Singbin, Guoxiang, and Aotoucun.
NEIC reported intensity V in Taipei at Yungho and Sanchung and in Taoyuan and IV in Taichung and Kaohsiung.
Initial reports from CWB (Central Weather Bureau of Taiwan) gave this earthquake M 7.0.
CWB reported it was felt with intensity IV in Taiwan at Taipei, Hualien, Keelung City, Taoyuan, Hsinchu, Taichung, Nantou, Miaoli, Changhua, Yunlin, Taitung, Chiayi, Tainan, Kaohsiung, Pingtung, Lianjiang, Pengu and II in Kinmen County, Taiwan.
Initial reports did not report extensive damage but moderate damage would be
expected with this event. Loss of electricity, gas and water with minor damage to
buildings was reported in Yilan. Although high wave warning was issued for areas of Japan, no major
tsunami was expected nor observed. Some loss of property and a few injuries were
reported on the internet. High Rise building shook in Taipei, the capitol.
There were no immediate deaths or major injuries reported. The earthquake occurred near local solar midnight on
a weekend in the Christmas/New Year's season so many were out celebrating
and dining even at this late hour.
This earthquake follows an M 6.1 in Taiwan near the same epicenter which occurred
on December 24, 2025. At the time this summary noted:
"A strong M 6.0 occurred today in the region of southern Taiwan. NEIC reported it was
felt with intensity VI in Taiwan at Taitung; IV in Changhua, Kaohsiung, and III in Pingtung, Taipei, Kaohsiung and Yunlin, Taiwan.
CWB, the local network gave this earthquake M 6.1. That network reported intensity
up to V in Taitung with IV in Hualien, Kaohsiung, III in Nantou, Tainan, Chiayi, Changhua, Taichung, Miaoli, Yilan, Hsinchu, Taoyuan, Taipei, Pingtung, and Penghu Counties, Taiwan.
A foreshock of M 4.9 about 100 km north of the mainshock occurred about a day earlier
CWB reported this earthquake was felt with intensity III in Taiwan in Hualien, and II in Taitung, Taichung, Yunlin, Chiayi, Changhua Counties.
The last earthquake in Taiwan with M>=6.1 was recorded by NEIC as occurring
on August 15, 2024 with M 6.1 but the last of significantly larger magnitude
was an M 7.5 on April 2, 2024. At the time this summary noted:
"A major M 7.4 earthquake damaged much of the Island of Taiwan today. International Press reports indicated that this event and several
strong aftershocks killed at least 7 while injuring more than 700. The quake
occurred about 20 km south of Hualien and damaged and toppled buildings while
causing many damaging landslides. It is the strongest earthquake to hit
Taiwan in at least 25 years - since September 20, 1999 (M 7.7) - the strongest
event in Taiwan in the past 35 years. Major earthquakes have most recently
hit with M>=7.5 in Taiwan on November 14, 1986 (M 7.8); July 24, 1978 (M 8.0); April 24, 1972 (M 7.7) and January 25, 1972 (M 7.7)." (April 2, 2024)
Today's event in Taiwan may have also been promoted by a moderate solar
flare which began about the same time as the flare. This C4.9 flare
is the strongest in several days. Preliminary data on this flare from SWPC
follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1415 1420 1435 C2.4 (December 27, 2025) 2.4E-03 *
XXXX 0945 1021 1140 C4.9 (December 24, 2025) 1.4E-02 *
Taiwan M 6.0 09:47 UT ... " (December 24, 2025)
Today's earthquake in Taiwan occurred near the antipode of an M 5.6 earthquake at a
deep focus in Argentins earlier in the day and may have been promoted
by energy from that source. Despite the near-antipodal nature of these two
earthquake historical evidence does not support antipodal triggering in this case.
The last earthquake within about 200 km of this epicenter in Argentina with M>=5.6
occurred as an M 5.7 on October 2, 2025. At the time this summary noted:
"The strongest earthquake of the day was an M 5.7 in eastern Argentina near the border with Paraguay.
NEIC reported this event was probably felt lightly in the area of Hoyo, Argentina.
It occurred at a deep focus of 571 km and would not have been felt strongly
on the surface. The last earthquake at deep focus within about 200 km of this
epicenter with M>=5.7 occurred as an M 6.2 on August 23, 2023 following a series
of such events in 2023 after an M 6.8 on January 20, 2023. A series of
events of M>6 also occurred near this epicenter in 2011 and 2012 following an M 7.0 on January 1, 2011.
...
This epicenter is located near the antipode of several recent
typhoons in the Hong Kong, China area and may have been promoted by energy
associated with those sources. It is also at the fourth node (90 degrees)
from the South Geomagnetic Pole and at the third node (120 degrees) from the
North Geomagnetic equator in the South American/Atlantic geomagnetic anomaly
zone. Geomagnetic stresses associated with the current strong geomagnetic
storm probably helped promote today's earthquake in Argentina." (October 2, 2025)
O: 27DEC2025 10:40:50 28.3S 63.2W MW=5.6 EMSC SANTIAGO DEL ESTERO, ARGENTINA
Today's event may also have been promoted by a c-class solar flare. Preliminary
data on this flare from SWPC is in the table above. Taiwan was also near
local solar noon when the M 5.8 flare occurred earlier on December 27
see discussion below).
This epicenter is located at 144 degrees from the Drake Passage and at
the fifth node (72 degrees) from the Yukon, Canada and may have been promoted by
constuctive interference of energy from those two sources. It is also located
at the sixth node (60 degrees) from the north Geomagnetic pole.
O: 27DEC2025 15:05:56 24.7N 122.1E mw=7.0 CWB TAIWAN REGION
O: 27DEC2025 15:05:56 24.7N 122.1E MW=6.6 EMSC TAIWAN REGION
O: 27DEC2025 11:47:35 24.5N 122.9E mb=4.5 EMSC TAIWAN REGION
O: 27DEC2025 16:45:42 24.6N 122.1E mb=4.5 EMSC TAIWAN REGION
"Far-field earthquake triggering is possible with earthquakes of M 7.5 or greater.
In the case of Taiwan, the most likely triggering zones - near 144 degrees and
103 degrees from Taiwan do not contain many areas of high seismicity and far-field
triggering is likely to be muted. Following is a listing of potential triggering
sites with this earthquake:
180 degrees: Brazil, Argentina,
144 degrees: Panama, Colombia, South Sandwich Islands, East Pacific Rise, eastern Caribbean, Venezuela
120 degrees: Western Mexico, Michoacan, Jalisco, SE U.S., Northern Mid-Atlantic,
103 degrees: Southern, Baja California, Utah, Nunuvat, Ontario, Quebec Canada, South Africa, Spain, Morocco, Portugal,
90 degrees: Northwest U.S., Italy, Mediterranean, East Africa Rift,
72 degrees: Tonga, Fiji, Kermadec Is. Turkey,
60 degrees: Iran, Fox Islands,
52 degrees: Rat, Andreanof Is, Pakistan" (April 3, 2024)
The series of earthquakes in the San Francisco Bay area of California on the
northern Calaveras fault appears to have come to a temporary halt following
the earthquake in Taiwan. The distance between these two areas is 96 degrees
and is not nodal. There has been a tendency for larger quakes of M>=4.5 to
occur about 5 days after major events in Taiwan. This occurred in 1906 when
an M 7.2 in Taiwan was followed by the M 8.1 in San Francisco on April 18, 1906.
Earthquake of M>=5.0 in the San Francisco Bay area also occurred in the first 10 days after major
events in Taiwan in March, and January, 1986; September, 1935; August, 1989.
If this lull in Central California is precursory a moderate quake may
occur in this area in the next 5-10 days. A moderate watch for the area
is now in effect through January 7, 2026. Southern California and Baja California
are closer to 103 degrees from Taiwan. Even so, there is scant evidence
in the historical record that these areas are likely to see enhanced
seismicity at this time. A pair of quakes in the Los angeles area of 2.7 and M 2.5
preceded the Taiwan quake by about 30 minutes today. A similar M 4.5
in Los Angeles followed an M 6.6 in Taiwan at the same location as today's
event a day later on May 24-25, 1994. The only other activity on record
of M>=4.5 associated with major earthquakes in Taiwan occurred in April, 1910
and September 4, 1935. This area is not under watch from the Taiwan earthquake at this time.
Seismic waves from the earthquake in Taiwan may have triggered an M 3.8 in northern
Yerington, Nevada minutes later. NEIC reported this far-field aftershock was
felt in Silver Springs, Nevada with III and in Yerington, Nevada with intensity II.
The Nevada quake occurred 14.5 minutes arger the evne in Taiwan. The p-wave from
Taiwan would have arrived seconds before the subsequent event in Nevada
at 96 degrees from Taiwan.
This epicenter is at the fifth node from Hokkaido Japan (72 degrees) and at 103 degrees from
Central Philippines and may have been promoted by energy from those two sources.
O: 27DEC2025 15:20:28 39.2N 119.1W mb=3.7 NEIC NEVADA
A strong M 6.2 earthquake was recorded today off the coast of northern Peru. NEIC reported
it was felt with intensity V in Casma, Ancash, Peru and IV in La Libertad at Huanchanco, Paijan, Trujillo, Pacasmayo; III in Santiago de Chuco and in Lima at Caleta de Carquin, and San Luis. It was also felt with light entensity in Peru at Eten, Lambayeque and Celendin, Cajamarca.
EMSC reported moderate shaking in Peru at Chimbote, La Esperanza, Cajamarca, Independencia, Lima, Jesus Maria, San Isidro, San Francisco De Borja, Santiago de Surco, Cieneguilla.
This earthquake occurr several hour before midnight local solar time. The last
earthquake in Peru within about 200 km of this epicenter with M>=6.2 occurred
as an M 6.3 on February 24, 2007. A major earthquake hit the region on February 21, 1996 with M 7.5.
This epicenter is located on the geomagnetic equator and may have been
promoted by tidal and/or geomagnetic effects. Today's event was off the coast
so hazards were minimal to local populations.
This epicenter is at the seventh node (52 degrees) from the Drake Passage
and at 102 degrees from the North Geomagnetic pole and may have been promoted by energy from those sources.
O: 28DEC2025 02:51:49 9.0S 79.0W MW=6.2 EMSC NEAR COAST OF NORTHERN PERU
O: 28DEC2025 03:51:28 9.0S 79.2W ML=4.1 EMSC NEAR COAST OF NORTHERN PERU
O: 28DEC2025 05:17:22 9.1S 79.3W ML=4.3 EMSC OFF COAST OF NORTHERN PERU
NEIC reported an earthquake of M 4.7 in Central Luzon, Philippines was felt with intensity up to II-III in the area(s) of Central Luzon, Philippines with IV in Nambalan and III inMasinloc, Cabangan and Manila.
EMSC reported gentle swaying in Philippines at Balibago and Quiapo.
O: 27DEC2025 18:26:23 15.4N 120.1E MB=4.7 EMSC LUZON, PHILIPPINES
NEIC reported an earthquake of M 3.3 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii in Kailua Kona.
This epicenter is at 76 degrees from Taiwan and occurred as SSS-phase seismic waves
and body waves from Taiwan arrived in the area. It was probably promoted
by energy associated with those waves.
O: 27DEC2025 15:34:51 19.2N 155.5W ML=3.3 EMSC ISLAND OF HAWAII, HAWAII
NEIC reported earthquakes of M 2.5 and M 2.7 in western Los Angeles, California were felt with intensity up to II-III in the area(s) of California at Valenci, Stevenson Ranch, Newhall, Santa Clarita, Castaic.
These epicenters are at the fifth node (72 degrees) from Hokkaido; the sixth node (60 degrees)
from Kamchatka and 105 degrees from the Drake Passage and Mindanao and at
146 degrees from TC Grant and may have been promoted by energy from those
sources.
O: 27DEC2025 14:25:40 34.4N 118.6W ML=2.7 EMSC GREATER LOS ANGELES AREA, CALI
O: 27DEC2025 14:34:52 34.4N 118.6W ML=2.5 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 2.9 in the Texas-Louisiana border was felt with intensity up to II-III in the area(s) of the Texas-Louisiana border in Pleasant Hill, Louisiana.
This epicenter is at the fouorth node (90 degrees) from Hokkaido, Japan and at
the fith node from Kamchatka and may have been promoted by energy from those
sources.
O: 27DEC2025 12:47:51 31.9N 93.5W ML=2.9 EMSC LOUISIANA-TEXAS BORDER REGION
NEIC reported an earthquake of M 4.5 in Assam, India was felt with intensity up to II-III in the area(s) of Assam, India in Itanagar Arunachal Pradesh, India.
EMSC reported light shaking in India at Raha, Guwahati, Dispur, Mushalpur, Nongpoh, Ziro and Shillong.
O: 27DEC2025 12:42:49 26.7N 92.3E MB=4.5 EMSC ASSAM, INDIA
EMSC reported an earthquake of M 4.3 in Puerto Rico was felt with intensity up to IV in the area(s) of Puerto Rico in Mayaguez.
O: 28DEC2025 04:59:06 18.1N 68.2W MD=4.3 EMSC MONA PASSAGE, DOMINICAN REPUBL
O: 27DEC2025 22:31:30 18.8N 68.5W MD=3.5 EMSC DOMINICAN REPUBLIC REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE 10S
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 10S 2025-12-28 00:00 UT 12.8S 119.5E 45 kts North of western Australia
Tropical Cyclone 10S formed today in the region north of western Australia winds up to 45 kts. It could continue promote enhanced seismicity in this area. The antipode is at 12N 61W - is in the area north of Venezuela and Trinidad and Tobago where enhanced antipodal activity is possible as this storm makes landfall today and tomorrow.
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-28 00:00 UT 12.3S 86.7E 80 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 80 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 93W - is east of Central America where enhanced antipodal activity is possible, but unlikely as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica off the west coast of Central America around December 27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 27, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
6060 0023 0032 0038 C4.8 (December 27, 2025) 3.0E-03
Sumatra M 5.9 00:23 UT
6110 0110 0150 0159 M5.1 (December 27, 2025) 3.8E-02 *
Sumatra M 5.8 01:10 UT
6130 0532 0539 0541 C3.7 (December 27, 2025) 1.7E-03
Fiji M 4.5 05:45 UT
Nevada M 2.1, 2.1 05:30, 05:34 UT
6150 0640 0647 0650 C2.8 (December 27, 2025) 1.6E-03
6170 0744 0758 0816 C4.5 (December 27, 2025) 7.2E-03
6190 1024 1029 1036 C2.5 (December 27, 2025) 1.9E-03
Tarapaca M 4.7 10:26 UT
Argentina M 5.6 10:40 UT
6210 1322 1329 1332 C3.7 (December 27, 2025) 2.0E-03
Oaxaca M 4.0 13:25 UT
6220 1411 1415 1419 C3.2 (December 27, 2025) 1.6E-03
Los Angeles CA M 2.7 14:25 UT M 2.5 14:34 UT
6230 1535 1550 1609 C2.9 (December 27, 2025) 5.4E-03
Taiwan M 6.6 15:06 UT
Hawaii M 3.3 15:35 UT
Tarapaca M 4.2 15:51 UT
6250 2143 2148 2155 C2.4 (December 27, 2025) 1.7E-03
Baja M 3.4 21:45 UT
Kermadec M 3.9 21:51 UT
6270 2214 2233 2250 C9.8 (December 27, 2025) 1.4E-02
Izu Is M 4.4 22:48 UT
Fiji M 4.8 22:11 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet December 28-30. Solar M-flare chance: 65% X-class: 20% proton storm: 15%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 7 7 5 13:00 3 130 178
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 27, 2025
Notable earthquakes and events:
The strongest earthquake in the world today was an M 5.7-5.9 south of Sumatra,
Indonesia. BMG reported it was felt in the Bengkulu area of Sumatra with intensity
III at Enggano and II in Kab Ogan komering, Muara Eniam, Lahat, Selatan, Lawang, Pagar Alam, Kaur, Seluma, Kepahiang, among others.
An M 5.8 aftershock followed in the same area and was felt with similar
intensities and locations according to BMG data.
These epicenters in Sumatra are north of the eye of Tropical Cyclone Grant on December 25,
the only tropical cyclone currently active in the world at this time. This was discussed
in the previous issue of this summary as:
"Elsewhere in the world today was a particularly quiet day in seismicity. No
events of M>=5 were recorded by NEIC or EMSC (BMG reported an M 5.0 in the Talaud
Islands - M 4.6 by EMSC)." (December 26, 2023)
"The most likely activity to help promoted seismicity at this time in Tropical
Cyclone Grant. This cyclone is currently south of Sumatra where it has been
proposed in previous issues of this summary that it may help trigger a moderate
to strong earthquake to the north as for example:
"Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 50 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 78W - is in the area north of Colombia and Panama where enhanced antipodal activity is possible as this storm moves to the west." (December 22-23, 2025)
or more recently in the last issue of this summary:
"Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 55 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 84W - is in the area of eastern Costa Rica and east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica around December 25-27, the most likely time for a significant regional earthquake." (December 25, 2025)
A foreshock of M 3.6 hit today's epicenter on December 25 and was noted
at the time in this summary as:
O: 25DEC2025 18:17:52 5.5S 102.4E ML=3.6 EMSC SOUTHERN SUMATRA, INDONESIA
This epicenter is at the sixth node (60 degrees) from Hokkaido, Japan and may have been promoted by energy from that source." (December 25-26, 2025)
Today's mainshock appears to have been triggered by a moderate C4.8 solar
flare which began at the same time of this event of M 5.9 in Sumatra. The
strong aftershock of M 5.8 may have been promoted by an M5.2 class solar
flare which appears to have begun at the same time as that aftershock.
Preliminary data from SWPC on these events follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0015 0030 0100 C4.8 (December 27, 2025) 4.8E-03 *
Sumatra M 5.9 00:22 UT
XXXX 0110 0200 0300 M5.2 (December 27, 2025) 5.1E-02 *
Sumatra M 5.8 01:10 UT
These events in Sumatra are located at the sixth node (60 degrees) from Hokkaido,
Japan and may have been promoted by energy from that source.
O: 27DEC2025 00:22:31 5.4S 102.3E ML=5.6 EMSC SOUTHERN SUMATRA, INDONESIA
O: 27DEC2025 00:22:32 5.6S 102.3E ML=5.9 BMG SOUTHERN SUMATRA, INDONESIA
O: 27DEC2025 01:10:12 5.4S 102.3E ML=5.2 EMSC SOUTHERN SUMATRA, INDONESIA
O: 27DEC2025 01:10:12 5.6S 102.2E ML=5.8 BMG SOUTHERN SUMATRA, INDONESIA
NEIC reported an earthquake of M 4.6 in Lima, Peru was felt with intensity up to II-III in the area(s) of Lima, Peru in Lima, Santa Maria and San Luis.
EMSC reported moderate intensity in Oeru at Independencia, San Isidro, La Molina, Santiago de Surco.
O: 27DEC2025 00:35:20 11.0S 77.7W MB=4.6 EMSC NEAR COAST OF CENTRAL PERU
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-27 00:00 UT 11.8S 90.1E 75 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 75 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 89W - is in the area of El Salvador and Nicaragua east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica off the west coast of Central America around December 27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 26, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0022 0030 0100 C4.8 (December 27, 2025) 4.8E-03 *
Sumatra M 5.9 00:22 UT
XXXX 0110 0150 0300 M5.2 (December 27, 2025) 5.1E-02 *
Sumatra M 5.8 01:10 UT
5940 0305 0320 0326 C2.4 (December 26, 2025) 3.3E-03
Sumatra M 3.4, 3.0 03:07, 03:11 UT
5960 0326 0332 0335 C2.6 (December 26, 2025) 1.6E-03
Peru M 3.6 03:29 UT
5970 0725 0729 0731 C3.5 (December 26, 2025) 1.3E-03
Colombia M 3.6 07:30 UT
Loyalty Is. M 4.9 07:45 UT
5990 0810 0815 0840 C2.2 (December 26, 2025) 4.0E-03
Fiji M 5.6 08:36 UT
6000 0909 0914 0917 C6.9 (December 26, 2025) 2.5E-03
6010 1021 1028 1037 C4.0 (December 26, 2025) 3.7E-03
Oaxaca M 4.1 10:41 UT
Izu Is. M 4.8 10:44 UT
6050 1915 1923 1932 C2.7 (December 26, 2025) 2.6E-03
Fiji M 4.6 19:27 UT
Xinjiang, China M 4.2 19:44 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet December 27-29. Solar M-flare chance: 45% X-class: 5% proton storm: 5%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 8 13 6 13:00 4 131 166
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 26, 2025
Notable earthquakes and events:
It was a relatively quiet day in global seismicity. There were no major solar
flares or geomagnetic storms. This level of global seismicity is not uncommon
at this time of year as reported in this summary two years ago (for example):
"Elsewhere in the world today was a particularly quiet day in seismicity. No
events of M>=5 were recorded by NEIC or EMSC (BMG reported an M 5.0 in the Talaud
Islands - M 4.6 by EMSC)." (December 26, 2023)
But major earthquakes have occurred at this time including an M9+ event
in Indonesia on December 26, 2004 as reported last year at this time in this
summary:
"December 26 also marks the 20th anniversary of one of the largest and deadliest
tsunamis in history. This tsunami began near Sumatra, Indonesia and killed
up to 250,000 people as it ravaged the coastlines of the Indian Ocean.
This summary has previously discussed this tsunami as:
"12 26 04 21 25 2004 6.890 92.890 10 7.5 NICOBAR ISLANDS, INDIA
(GS). This is the fourth largest earthquake in the world since 1900 and is the largest since the 1964 Prince William Sound, Alaska earthquake. In total, more than 283,100 people were killed, 14,100 are still listed as missing and 1,126,900 were displaced by the earthquake and subsequent tsunami in 10 countries in South Asia and East Africa. The earthquake was felt (IX) at Banda Aceh, (VIII) at Meulaboh and (IV) at Medan, Sumatra and (III-V) in parts of Bangladesh, India, Malaysia, Maldives, Myanmar, Singapore, Sri Lanka and Thailand. The tsunami caused more casualties than any other in recorded history and was recorded nearly world-wide on tide gauges in the Indian, Pacific and Atlantic Oceans. Seiches were observed in India and the United States. Subsidence and landslides were observed in Sumatra. A mud volcano near Baratang, Andaman Islands became active on December 28 and gas emissions were reported in Arakan, Myanmar." (December 26, 2023, 2024 ...)
This summary was expecting a major event was likely at the time of this
tsunami following an M 8.2 near Australia and New Zealand two days before
the event in Indonesia on Boxing Day, 2004. At the time this summary (prior
to the event of December 26, 2004) and noted:
"A great earthquake of M 8.1 (NEIC) was located by the National Earthquake
Information Center. The earthquake was located about 800 km off the coast
of Tasmania and was felt in Tasmania lightly. The last earthquake of similar
size on the Macquarie Rise occurred in 1924. ..." (December 24, 2004)
"When great earthquakes occur with strike-slip mechanism (which causes horizontal
movements in the earth's crust) there is usually a quiet period in global
seismicity lasting for up to 3-4 days following the great quake followed
by a dramatic increase in global seismicity." (December 25, 2004)
At the time this summary was in negotiations with insurance agencies for
usage of data so this information was not widely publicized.
This summary issues sincere sympathies and condolences to nations and people affected
by this earthquake and tsunami of 20 years ago, hoping that more recent
improvements in tsunami observations and networks will mitigate future
tsunami disasters of this magnitude." (December 26, 2024)
The most likely activity to help promoted seismicity at this time in Tropical
Cyclone Grant. This cyclone is currently south of Sumatra where it has been
proposed in previous issues of this summary that it may help trigger a moderate
to strong earthquake to the north as for example:
"Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 50 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 78W - is in the area north of Colombia and Panama where enhanced antipodal activity is possible as this storm moves to the west." (December 22-23, 2025)
or more recently in the last issue of this summary:
"Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 55 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 84W - is in the area of eastern Costa Rica and east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica around December 25-27, the most likely time for a significant regional earthquake." (December 25, 2025)
Areas north of TC Grant and near the antipode in Nicaragua and El Salvador
continued to show moderate seismicity at this time and a moderate to strong
earthquake may still be in the works. Some of the earthquakes in the region
today included:
O: 25DEC2025 14:06:47 4.1N 97.5E ML=4.1 EMSC NORTHERN SUMATRA, INDONESIA
O: 26DEC2025 06:51:05 4.1N 97.4E ML=4.1 EMSC NORTHERN SUMATRA, INDONESIA
This epicenter is at 102 degrees from Yukon, Canada and at the fifth node (72 degrees)
from Kamchatka and may have been promoted by energy from those sources.
O: 25DEC2025 18:17:52 5.5S 102.4E ML=3.6 EMSC SOUTHERN SUMATRA, INDONESIA
This epicenter is at the sixth node (60 degrees) from Hokkaido, Japan and may have been promoted by energy from that source.
While that near the antipode included:
O: 25DEC2025 13:40:04 8.4N 82.9W ML=4.2 EMSC PANAMA-COSTA RICA BORDER REGIO
O: 26DEC2025 05:28:30 9.7N 83.9W ML=3.3 EMSC COSTA RICA
O: 26DEC2025 06:31:30 11.6N 88.5W ML=3.8 EMSC OFF COAST OF CENTRAL AMERICA
O: 26DEC2025 01:54:00 13.3N 89.5W ML=4.2 EMSC OFFSHORE EL SALVADOR
O: 26DEC2025 08:00:59 13.2N 90.4W ML=4.0 EMSC OFFSHORE EL SALVADOR
A series of light earthquakes occurred today in western Texas. The largest of
these was M 3.5. NEIC reported it was likely felt in the area of Whites City, New Mexico with
intensity up to IV.
O: 25DEC2025 19:31:42 31.3N 103.6W ML=2.0 EMSC WESTERN TEXAS
O: 25DEC2025 17:11:14 31.5N 104.5W ML=2.0 EMSC WESTERN TEXAS
O: 26DEC2025 01:15:26 31.5N 104.0W ML=2.0 EMSC WESTERN TEXAS
O: 26DEC2025 05:10:50 31.5N 104.0W ML=2.8 EMSC WESTERN TEXAS
O: 25DEC2025 18:46:56 31.6N 104.4W ML=2.5 EMSC WESTERN TEXAS
O: 25DEC2025 21:46:03 31.6N 104.4W ML=2.6 EMSC WESTERN TEXAS
O: 25DEC2025 10:18:39 31.7N 104.2W ML=2.1 EMSC WESTERN TEXAS
O: 25DEC2025 18:26:37 31.7N 104.4W ML=3.3 EMSC WESTERN TEXAS
O: 25DEC2025 18:29:44 31.7N 104.4W ML=2.3 EMSC WESTERN TEXAS
O: 25DEC2025 18:50:26 31.7N 104.4W ML=3.5 EMSC WESTERN TEXAS
O: 25DEC2025 19:23:19 31.7N 104.4W ML=2.1 EMSC WESTERN TEXAS
O: 25DEC2025 19:44:39 31.7N 104.4W ML=2.6 EMSC WESTERN TEXAS
O: 25DEC2025 19:53:31 31.7N 104.4W ML=2.7 EMSC WESTERN TEXAS
O: 26DEC2025 00:31:49 31.7N 104.4W ML=2.7 EMSC WESTERN TEXAS
O: 26DEC2025 00:38:39 31.7N 104.4W ML=2.0 EMSC WESTERN TEXAS
O: 25DEC2025 18:51:11 31.9N 104.0W ML=2.3 EMSC WESTERN TEXAS
O: 25DEC2025 18:27:20 32.0N 102.7W ML=2.9 EMSC WESTERN TEXAS
O: 25DEC2025 18:27:20 32.0N 102.7W ML=2.9 EMSC WESTERN TEXAS
O: 25DEC2025 09:52:00 32.1N 101.1W ML=2.2 EMSC WESTERN TEXAS
O: 26DEC2025 00:34:59 32.2N 102.2W ML=2.8 EMSC WESTERN TEXAS
NEIC reported an earthquake of M 4.4 in San Juan, Argentina was felt with intensity up to II-III in the area(s) of San Juan, Argentinan Monte Patria Coquimbo, Chile.
O: 26DEC2025 05:37:28 31.0S 69.9W MB=4.4 EMSC SAN JUAN, ARGENTINA
The latitude of sub-solar conditions today was around 22-23 degrees south latitude.
The sun is directly overhead at noon at this latitude on this day of the
year. In subduction zones this can provide efficient tidal stresses and
enhance seismicity at these latitudes. Some of the moderate-sized earthquakes near this latitude
range today occurred today at:
O: 25DEC2025 09:57:14 26.7S 176.0W MB=5.2 EMSC SOUTH OF FIJI ISLANDS
O: 26DEC2025 04:55:16 22.6S 67.7W MB=4.2 EMSC POTOSI, BOLIVIA
This event occurred within minutes of local solar midnight.
O: 25DEC2025 20:59:33 22.4S 66.3W ML=4.0 EMSC JUJUY, ARGENTINA
O: 26DEC2025 09:50:55 21.1S 68.7W MB=4.3 EMSC ANTOFAGASTA, CHILE
O: 25DEC2025 21:26:53 21.5S 68.7W mb=4.0 EMSC ANTOFAGASTA, CHILE
O: 26DEC2025 07:45:39 21.0S 168.7E MB=4.9 EMSC LOYALTY ISLANDS
O: 26DEC2025 07:14:06 16.3S 66.8E MB=4.8 EMSC MID-INDIAN RIDGE
This event occurred within minutes of local solar noon.
NEIC reported an earthquake of M 2.9 in Central California near Templeton was felt with intensity up to II-III in the area(s) of Central California near Templeton with III in Templeton and II in Paso Robles and Atascadero.
O: 25DEC2025 23:41:47 35.5N 120.8W MD=2.9 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.6 in Gujarat, India was felt with intensity up to II-III in the area(s) of Gujarat, India near Bhuj.
The is the largest earthquake in the Gujarat, India area within about 200 km
of this epicenter since an M 5.1 on June 14, 2020 and an M 5.0 on June 19, 2012. At these times this summary
noted:
"An M 5.1-5.5 also shook regions of Guharat, India today. NEIC reported it was felt with intensity V in Gugarat at Bhachau, Anjar, and Shuj; IV in Gandhi Dham, Dandia, Maliya, Barwala, Morvi, Mundra and Tankara.
The India Meterological Department (IMD) reported the quake at M 5.3-5.5 and that
it was felt in Kutch, Rajkot, Ahmedabad, Patan and other areas. People rushed
from their homes and collected on the streets. No major damages or loss of life
accompanied this earthquake." (June 14, 2020)
and
"A moderate earthquake of M 5.0 also shook much of the region of Gujarat,
India today. NEIC reported this earthquake was felt with the following intensities in India in Dadraand at Nagar Haveli Silvassa (2),
and in Gujarat at Ahmadabad (3), Anjar (4), Bhachau (4), Bhanvad (4), Chandkheda (3), Chandlodiya (4), Gandhi Dham (3), Gandhinagar (2), Jamnagar (4), Kadi (2), Kosamba (4),
Lalpur (4), Mahesana (3), Morvi (3), Porbandar (3), Rajkot (3), Sarkhej (4), Surat (3), Vadodara (4), and in Pakistan at Sind Badin (2).
Some damage is expected but local news reported no immediate loss of life
of major damage to property. Tremors were also felt in Bhavnagar, Jamnagar,
Rajkot and Ahmedabad. Several aftershocks were felt in the Dholavira area.
The only earthquake of similar or larger magnitude in Gujarat area of India
in the past four years was an M 5.0 on October 20, 2011. Today's event is the
strongest aftershock of the M 7.7 of January 26, 2001 since an M 5.5 on
April 6, 2006. The mainshock of 2001 killed tens of thousands and did billions
in damage to the region." (June 19, 2012)
This epicenter is at the fourth node from Yukon, Canad; the fifth node from Kamchatka; the sixth node from Hokkaido and the seventh
node from Central Philippines and may have been promoted by energy from those sources.
O: 25DEC2025 23:00:05 23.7N 70.3E MB=4.6 EMSC GUJARAT, INDIA
NEIC reported an earthquake of M 2.5 in Los Angeles California was felt with intensity up to II-III in the area(s) of Los Angeles California in Stevenson Ranch and Oxnard.
O: 25DEC2025 22:45:07 34.4N 118.6W ML=2.5 EMSC GREATER LOS ANGELES AREA, CALI
NEIC reported an earthquake of M 4.5 in New Zealand north of Wellington was felt with intensity up to II-III in the area(s) of New Zealand north of Wellington with III in Palmerston, North Manawatu-Wanganui and in Masterton with II.
GeoNet reported the following parameters for this earthquake:
O: 25DEC2025 18:16:50 40.6S 176.1E ML=4.8 GEONET Felt with moderate to light intensity in the area southeast of Wellington, New Zealand and in southern North Island and northern South Island. 2184 reports of felt events were made of which 1293 reported weak and 767 light intensity with 120 reports of moderate shaking and 4 with strong and 0 severe and 0 with extreme intensity came from the area.
O: 25DEC2025 18:16:50 40.7S 176.2E MW=4.5 EMSC NORTH ISLAND OF NEW ZEALAND
The strongest earthquake in the world today was an M 5.6 in the area of Hokkaido, Japan. NEIC reported
it was probably felt in the epicentral area near Yokohama, Japan with intensity
up go IV. It continued moderate aftershocks in the region of Hokkaido
following an M 7.6 on December 8, 2025.
O: 25DEC2025 16:17:41 41.2N 142.5E MW=5.6 EMSC HOKKAIDO, JAPAN REGION
O: 25DEC2025 16:25:50 41.3N 142.5E mb=4.6 EMSC HOKKAIDO, JAPAN REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-26 00:00 UT 11.9S 94.5E 65 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 65 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 85W - is in the area of eastern Costa Rica and Nicaragua east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica around December 25-27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 25, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5810 0417 0424 0426 C2.6 (December 25, 2025) 1.3E-03
Banda Sea M 4.2 04:19 UT
Fiji M 4.3 04:29 UT
5820 0601 0609 0616 C2.3 (December 25, 2025) 2.0E-03
Guatemala M 4.1 06:06 UT
Kuril Is M 4.1 06:22 UT
5880 2147 2153 2156 C2.4 (December 25, 2025) 1.3E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled December 26 quiet December 27-28. Solar M-flare chance: 40% X-class: 5% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 11 17 8 11:00 4 113 163
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 25, 2025
Notable earthquakes and events:
The strongest earthquake in the world today was an M 5.7 south of Guam. It followed events of M 5.1 and M 4.9
in the area of Guam. The mainshock was reported by NEIC to have been felt with intensity II
in Yona, Guam. The M 5.0 foreshock in Guam was reported with intensity IV in Guam at Asan, Tamuning and III in Nangilao, Yona and Santa Rita.
The mainshock of M 5.7 occurred within about an hour of local
solar midnight and may have been promoted by tidal and/or geomagnetic effects
which often maximize near this hour. The last earthquake within about 200
km of today's M 5.7 with equal or greater magnitude was an M 5.9 on November 4, 2025.
At the time this summary noted in this regard:
"The strongest earthquake in the world today outside of Kamchatka was an M 5.9
south of Guam. NEIC reported it was felt with intensity III in Guam at Tamuning, Yigo, Hagatna and Hagatna Heights.
This earthquake may have been triggered by Typhoon Kalmaegi as that storm
passed near Guam on October 31 and November 1, 2025 as noted at the time in this
summary:
"TS Kalmaegi formed today in the region of the north Pacific southwest of Guam with winds up to 50 kts. It could help promote moderate seismicity as it tracks to the west encounter Leyte and Samar, Philippines around November 3, 2025 as a typhoon. The area is currently experienceing aftershocks from major events lat month and could see a further significant event with Typhoon Kalmaegi. A moderate to moderately strong earthquake is possible in the area at this time with the full moon of November 6. The antipode is at 11S 44E - is in the South Atlantic near Brazil and is not likely to see seismic enhancement at this time." (November 1, 2025)
A second storm (TD 32W) also formed south of Guam today and also probably
provided energy helping to promote today's event of M 5.9 in Guam. This
was described in this summary as:
"TD 32W formed today in the region south of Guam with winds up to 45 kts. It could help promote moderate seismicity in Guam in the next several days. The antipode is at 10S 37W in the South Atlantic and is not expected to see enhanced seismicity at this time." (November 4, 2025)
The last earthquake reported in the region of Guam with M>=5.9 occurred on
August 10, 2025 with M 5.9 and also with M 5.9 on June 23, 2020. The last of larger
magnitude within about 200 km of today's epicenter was an M 6.7 on September 17, 2014.
At the time this summary noted:
"A major earthquake of M 6.6-7.1 hit the region of Guam in the Mariana Islands today.
This is the first of several strong earthquakes expected from the results of the
X-flare and geomagnetic storm of the past five days. But in addition to solar
flare effects (SFE) and geomagnetic induction effects, the area has also been
subject to two major tropical storms in the past week and was situated near maximum
tidal effects from the full moon of September 9. All of these probably played
a triggering role in this earthquake in Guam today, the largest in that region
since events of M 6.6 and 6.9 on August 13 and 14, 2010 and of M 6.7 on May 9, 2008.
Today's event was given M 6.7-7.1 by NEIC which reported it was felt with intensity
V in Guam at Tamuning, Barrigada, Yona, Umatacm, Mangilao, Yigo, Talofofo; IV in Hagatna, Dededo, Santa Rita, Asan, Sinajana and in the Mariana Islands at Gualo Rai and Koblerville, Saipan, and in Tota and Tinian with intensity III-IV.
It was preceded three minutes earlier by an M 5.6 in Vanuatu and followed three minutes later by an M 4.7 in Pakistan in the Hindu Kush region.
As this earthquake was at more than 100 km depth effects on the surface were
mitigated and no major damage or injuries were reported. Due to the depth
no tsunami was generated.
A new tropical cyclone is forming east of the Philippines and passed Guam several days ago. It is currently
located in the area west of Guam at 14N 137E with winds up to 23 kts.
On meteorological grounds, the earthquake in Guam had been anticipated in the last three summaries as follows:
"Typhoon Kalmaegi (Depression 15W) continued over the northern Philippine Islands with winds up to 80 kts.
It is expected to move to the west and pass over northern Philippines around September 15.
A seismic watch may be called as this storm approaches the Philippines. Some
increased seismicity in the Caroline and Mariana Islands may also occur." (September 12-15, 2014)
(editor's note - yes that reference to Typhoon Kalmaegi is correct for 2014. Tropical
Storm names are recycled and it happened that it is time for Kalmaegi to reused.)
A month ago this summary noted the relation between strong earthquakes in Guam
and regional tropical storms as follows:
"Seismicity in the region of Guam is often activated by strong storms
in that region. This results in a tendency for local seismicity to concentrate
in summer months. The largest recent earthquakes in the area occurred in late July,
2011 (M 5.6, 5.6); July and August, 2010 (M 5.5, 5.5). In the past 20 years
128 earthquakes of M>=5.3 have hit near Guam. Of these 45, nearly a third
have occurred in the summer monts of July, August and September while only
about 30 would have been expected by chance." (July 27, 2013, August 13, 2014)
Another triggering factor for this earthquake in Guam may have been tides from
the full moon of September 9. Maximum tidal stress occurred when Guam was sub-solar,
a time of maximum tidal stresses. This summary noted this at the time as follows:
"The full moon was complete at 01:38 UT on September 9. Areas which are sub-solar
at this time are within about 20 degrees of 22 West longitude and those at anti-solar
locations are within about 20 degrees of 158 East longitude. ... tidal triggering can occur in other
tectonic zones in which seismicity is moderated by fluids such as water or
magma. Seismicity in these regions could increase at this time." (September 8-13, 2014)
In addition to tidal and meteorological stresses, Guam is also located on the
geomagnetic equator. The strong X-ray flare and subsequent major geomagnetic
storm had been expected (in this summary) to bring about a strong earthquake
in this area at this time." (September 17, 2014, November 4, 2025)
Readers may also note that this event occurred at the same longitude (143-147 degrees)
as a current swarm in the southern Kuril Islands and at the same longitude
as the M 6.5 in New Guinea of December 23. The new moon of December 20, 2025
had been at local solar noon near this longitude and may have helped
promote the current seismicity as reported in previous issues of this summary:
"Like that event of October 7, 2025, today's event in New Guinea was also
closely associated with a soli-lunar alignment coming a day after the
new moon of December 20, 2025. It also occurred near the longitude
of maximum tidal stress with that alignment as noted in previous issues
of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-22, 2025)
These epicenters are at the eighth node from Kamchatka (45 degrees); the fifth node (72 degrees)
from Yukon, Canada and the seventh node from Tropical Cyclone Grant (52 degrees)
and may have been promoted by energy from those sources.
O: 24DEC2025 15:00:35 11.8N 143.3E MW=5.7 EMSC SOUTH OF MARIANA ISLANDS
O: 24DEC2025 13:33:58 13.0N 144.7E MB=5.0 EMSC GUAM REGION
O: 24DEC2025 22:37:31 11.8N 143.3E Mw=5.1 EMSC SOUTH OF MARIANA ISLANDS
NEIC reported an earthquake of M 2.8 in Washington State was felt with intensity up to II-III in the area(s) of Washington State with III in Port Orchard and II in Port Ludlow.
This earthquake occurred within minutes of local solar midnight and may have
been promoted by tidal and/or geomagnetic effects which maximize near this
hour.
This epicenter is at the eighth node (45 degrees) from Kamchatka and may have been
promoted by energy from that source.
O: 25DEC2025 07:58:27 47.5N 122.8W ML=2.8 EMSC PUGET SOUND REGION, WASHINGTON
NEIC reported an earthquake of M 3.0 in Southern California was felt with intensity up to II-III in the area(s) of Southern California with II in Cathedral City,Palm Springs, Rancho Mirage, Palm Desert, Rancho Cucamonga.
O: 24DEC2025 20:03:24 34.0N 116.8W ML=2.9 EMSC SOUTHERN CALIFORNIA
O: 24DEC2025 20:03:24 34.0N 116.8W ML=3.0 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.0 in the eastern San Francisco Bay, California area was felt with intensity up to II-III in the area(s) of the eastern San Francisco Bay, California area with III in San Ramon, Dublin, Pleasanton, Danville, San Francisco and II in Pleasanton, Danville, Castro Valley and Walnut Creek.
This earthquake occurred with minutes of local solar noon and may have been
promoted by tidal stresses which maximize near this hour. It continues a
series of light to moderate tremors in the area which have concentrated
near local solar noon and local solar midnight and may have been promoted
by tidal and/or geomagnetic stresses which maximize near those hours.
O: 24DEC2025 19:36:54 37.7N 122.0W ML=3.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 2.6 in Malibu, California was felt with intensity up to II-III in the area(s) of Malibu, California with II in Malibu, Westlake Village, Newbury Park and Agoura Hills and Santa Monica.
An aftershock of M 2.2 occurred within minutes of local solar noon and may have
been promoted by tidal stresses.
O: 24DEC2025 17:08:39 34.0N 118.9W ML=2.7 EMSC CHANNEL ISLANDS REG., CALIFORN
O: 24DEC2025 17:08:39 34.0N 118.9W ML=2.6 NEIC CHANNEL ISLANDS REG., CALIFORN
O: 24DEC2025 20:30:46 34.9N 119.0W ML=2.2 EMSC CENTRAL CALIFORNIA
A strong M 6.0 occurred today in the region of southern Taiwan. NEIC reported it was
felt with intensity VI in Taiwan at Taitung; IV in Changhua, Kaohsiung, and III in Pingtung, Taipei, Kaohsiung and Yunlin, Taiwan.
CWB, the local network gave this earthquake M 6.1. That network reported intensity
up to V in Taitung with IV in Hualien, Kaohsiung, III in Nantou, Tainan, Chiayi, Changhua, Taichung, Miaoli, Yilan, Hsinchu, Taoyuan, Taipei, Pingtung, and Penghu Counties, Taiwan.
A foreshock of M 4.9 about 100 km north of the mainshock occurred about a day earlier
CWB reported this earthquake was felt with intensity III in Taiwan in Hualien, and II in Taitung, Taichung, Yunlin, Chiayi, Changhua Counties.
The last earthquake in Taiwan with M>=6.1 was recorded by NEIC as occurring
on August 15, 2024 with M 6.1 but the last of significantly larger magnitude
was an M 7.5 on April 2, 2024. At the time this summary noted:
"A major M 7.4 earthquake damaged much of the Island of Taiwan today. International Press reports indicated that this event and several
strong aftershocks killed at least 7 while injuring more than 700. The quake
occurred about 20 km south of Hualien and damaged and toppled buildings while
causing many damaging landslides. It is the strongest earthquake to hit
Taiwan in at least 25 years - since September 20, 1999 (M 7.7) - the strongest
event in Taiwan in the past 35 years. Major earthquakes have most recently
hit with M>=7.5 in Taiwan on November 14, 1986 (M 7.8); July 24, 1978 (M 8.0); April 24, 1972 (M 7.7) and January 25, 1972 (M 7.7)." (April 2, 2024)
Today's event in Taiwan may have also been promoted by a moderate solar
flare which began about the same time as the flare. This C4.9 flare
is the strongest in several days. Preliminary data on this flare from SWPC
follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5780 0945 1021 1140 C4.9 (December 24, 2025) 1.4E-02 *
Taiwan M 6.0 09:47 UT
Chiapas M 4.3 10:00 UT
El Salvador M 4.1 10:08 UT
Andreanof Is. 10:57 UT
Mozambique M 3.0 10:57 UT
Fiji M 4.5 11:34 UT
O: 24DEC2025 09:47:07 22.9N 121.2E MW=6.0 EMSC TAIWAN REGION
O: 24DEC2025 09:47:05 22.9N 121.2E MW=6.1 CWB TAIWAN REGION
O: 23DEC2025 07:46:09 23.8N 121.7E MB=4.9 EMSC TAIWAN
O: 23DEC2025 07:46:09 23.8N 121.7E MB=4.8 CWB TAIWAN
P: 22DEC2025 178168 24.0N 122.0E 4.0-5.6 AAAAA Taiwan
The strongest earthquake in the U.S. or Canada today was an M 4.8 followed
by several lighter aftershocks in the region of the Andreanof Islands, Alaska.
NEIC reported it was probably felt with intensity up to III in the epicentral
area. This event occurred within minutes of local solar midnight and along with an aftershock
of M 3.9 may have been promoted by energy from tides and geomagnetic effects which tend
to maximize near this hour. This event occurred near the peak of the C4.9 solar
flare which also was associated with the M 6.1 in Taiwan 56 degrees distant and 70 minutes earlier (see above).
Seismic waves from Taiwan had already passed this area of the Andreanof Islands
when the M 4.8 occurred but may have contributed to destabilizing the area
leading to this earthquake in the Alaskan Aleutians.
The last earthquake within about 200 km of this event in the Andreanof Islands
with M>=4.8 was recorded by NEIC to have occurred on December 1, 2025 with M 5.1.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.1 in the eastern Andreanof Islands, Aleutians, Alaska.
NEIC reported it was felt with intensity II in Atka, Alaska. This event occurred
near local solar noon and may have been promoted by tidal or geomagnetic stresses
which maximize near this hour. This epicenter is at the 143 (node 5) degrees from the Drake Passage and
may have been promoted by energy from that source." (December 1, 2025)
O: 24DEC2025 03:14:52 51.3N 174.9W ML=3.5 EMSC ANDREANOF ISLANDS, ALEUTIAN IS
O: 24DEC2025 10:57:04 51.4N 174.9W mb=4.8 EMSC ANDREANOF ISLANDS, ALEUTIAN IS.
O: 24DEC2025 11:49:03 51.7N 175.1W mb=3.9 EMSC ANDREANOF ISLANDS, ALEUTIAN IS.
NEIC reported an earthquake of M 2.5 in Central California was felt with intensity up to II-III in the area(s) of Central California in Morgan Hill.
O: 24DEC2025 13:16:44 36.4N 121.0W MD=2.4 EMSC CENTRAL CALIFORNIA
O: 24DEC2025 12:31:44 36.8N 121.4W MD=2.5 EMSC CENTRAL CALIFORNIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-25 00:00 UT 11.9S 96.5E 55 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 55 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 84W - is in the area of eastern Costa Rica and east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica around December 25-27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 24, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5780 0948 1021 1140 C4.9 (December 24, 2025) 1.4E-02 *
Taiwan M 6.1 09:47 UT
Chiapas M 4.3 10:00 UT
El Salvador M 4.1 10:08 UT
Andreanof Is. 10:57 UT
Mozambique M 3.0 10:57 UT
Fiji M 4.5 11:34 UT
5790 2304 2313 2320 C2.7 (December 24, 2025) 2.3E-03
Azores M 4.6 23:18 UT
Kuril Is. M 4.9 23:00 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 25 unsettled December 26 quiet December 27. Solar M-flare chance: 30% X-class: 5% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 21 40 19 09:00 6 103 134
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 24, 2025
Notable earthquakes and events:
A moderate G1 geomagnetic storm occurred on December 24 beginning around 10:00 UT at
high latitudes with K-index of 6. Some enhanced seismicity is possible with
this storm including events near the International Date Line (IDL) and the
Greenwich Meridian in the first hours after the commencement of this storm.
A strong M 6.0 occurred today in the region of southern Taiwan. NEIC reported it was
felt with intensity VI in Taiwan at Taitung; IV in Changhua, Kaohsiung, and III in Pingtung, Taipei, Kaohsiung and Yunlin, Taiwan.
CWB, the local network gave this earthquake M 6.1. That network reported intensity
up to V in Taitung with IV in Hualien, Kaohsiung, III in Nantou, Tainan, Chiayi, Changhua, Taichung, Miaoli, Yilan, Hsinchu, Taoyuan, Taipei, Pingtung, and Penghu Counties, Taiwan.
A foreshock of M 4.9 about 100 km north of the mainshock occurred about a day earlier
CWB reported this earthquake was felt with intensity III in Taiwan in Hualien, and II in Taitung, Taichung, Yunlin, Chiayi, Changhua Counties.
The last earthquake in Taiwan with M>=6.1 was recorded by NEIC as occurring
on August 15, 2024 with M 6.1 but the last of significantly larger magnitude
was an M 7.5 on April 2, 2024. At the time this summary noted:
"A major M 7.4 earthquake damaged much of the Island of Taiwan today. International Press reports indicated that this event and several
strong aftershocks killed at least 7 while injuring more than 700. The quake
occurred about 20 km south of Hualien and damaged and toppled buildings while
causing many damaging landslides. It is the strongest earthquake to hit
Taiwan in at least 25 years - since September 20, 1999 (M 7.7) - the strongest
event in Taiwan in the past 35 years. Major earthquakes have most recently
hit with M>=7.5 in Taiwan on November 14, 1986 (M 7.8); July 24, 1978 (M 8.0); April 24, 1972 (M 7.7) and January 25, 1972 (M 7.7)." (April 2, 2024)
Today's event in Taiwan may have also been promoted by a moderate solar
flare which began about the same time as the flare. This C4.9 flare
is the strongest in several days. Preliminary data on this flare from SWPC
follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0945 1021 1140 C4.9 (December 24, 2025) 1.4E-02 *
Taiwan M 6.0 09:47 UT
Chiapas M 4.3 10:00 UT
El Salvador M 4.1 10:08 UT
Andreanof Is. 10:57 UT
Mozambique M 3.0 10:57 UT
Fiji M 4.5 11:34 UT
O: 24DEC2025 09:47:07 22.9N 121.2E MW=6.0 EMSC TAIWAN REGION
O: 24DEC2025 09:47:05 22.9N 121.2E MW=6.1 CWB TAIWAN REGION
O: 23DEC2025 07:46:09 23.8N 121.7E MB=4.9 EMSC TAIWAN
O: 23DEC2025 07:46:09 23.8N 121.7E MB=4.8 CWB TAIWAN
P: 22DEC2025 178168 24.0N 122.0E 4.0-5.6 AAAAA Taiwan
The strongest earthquake in the U.S. or Canada today was an M 4.8 followed
by several lighter aftershocks in the region of the Andreanof Islands, Alaska.
NEIC reported it was probably felt with intensity up to III in the epicentral
area. This event occurred within minutes of local solar midnight and along with an aftershock
of M 3.9 may have been promoted by energy from tides and geomagnetic effects which tend
to maximize near this hour. This event occurred near the peak of the C4.9 solar
flare which also was associated with the M 6.1 in Taiwan 56 degrees distant and 70 minutes earlier (see above).
Seismic waves from Taiwan had already passed this area of the Andreanof Islands
when the M 4.8 occurred but may have contributed to destabilizing the area
leading to this earthquake in the Alaskan Aleutians.
The last earthquake within about 200 km of this event in the Andreanof Islands
with M>=4.8 was recorded by NEIC to have occurred on December 1, 2025 with M 5.1.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.1 in the eastern Andreanof Islands, Aleutians, Alaska.
NEIC reported it was felt with intensity II in Atka, Alaska. This event occurred
near local solar noon and may have been promoted by tidal or geomagnetic stresses
which maximize near this hour. This epicenter is at the 143 (node 5) degrees from the Drake Passage and
may have been promoted by energy from that source." (December 1, 2025)
O: 24DEC2025 03:14:52 51.3N 174.9W ML=3.5 EMSC ANDREANOF ISLANDS, ALEUTIAN IS
O: 24DEC2025 10:57:04 51.4N 174.9W mb=4.8 EMSC ANDREANOF ISLANDS, ALEUTIAN IS.
O: 24DEC2025 11:49:03 51.7N 175.1W mb=3.9 EMSC ANDREANOF ISLANDS, ALEUTIAN IS.
An earthquake of M 4.5 in the Fiji Islands today also occurred within minutes
of local solar midnight. This event lies at a latitude which was sub-solar
at noon today and was probably promoted by tidal stresses. It was not reported
felt.
These epicenters are at the sixth node from central Philippines and at the
fourth node (90 degrees) from Yukon, Canada and may have been promoted by
enery from those sources.
O: 23DEC2025 20:32:21 25.0S 179.7E MB=4.5 EMSC SOUTH OF FIJI ISLANDS
O: 24DEC2025 11:34:39 24.2S 180.0E mb=4.5 EMSC SOUTH OF FIJI ISLANDS
A moderately strong earthquake of M 5.6 was also felt in the region of Central Vanuatu
today. NEIC reported it was felt with intensity III in Luganville Sanma.
This epicenter is located at the sixth node (60 degrees) from
the M 7.6 in Hokkaido and may have been promoted by energy from that source.
O: 23DEC2025 20:41:58 14.6S 167.2E MW=5.6 EMSC VANUATU
NEIC reported an earthquake of M 3.3-3.5 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii at Captain Cook, Naalehu and Kailua Kona.
O: 23DEC2025 09:56:57 19.2N 155.5W ML=3.5 EMSC ISLAND OF HAWAII, HAWAII
NEIC reported an earthquake of M 5.2 South of Honshu, Japan was felt with intensity up to II-III in the area(s) of South of Honshu, Japan in Fujisawa, Kanagawa.
EMSC reported light shaking in Tokyo and Urayasu, Japan.
This epicenter is near the sixth node (60 degrees) from Tropical Cyclone Grant and from
Yukon, Canada and may have been promoted by energy from those sources.
O: 23DEC2025 09:44:21 33.1N 137.8E MW=5.2 EMSC NEAR S. COAST OF HONSHU,
Earthquakes also continued today in the eastern San Francisco, California area on the
northern Calaveras fault. The strongest of today's events included an M 2.7 which
occurred within a minute of local solar midnight and was probably promoted
by tidal and/or geomagnetic stresses which maximize near this time of day.
NEIC reported these earthquakes were felt with intensity up to III in San Ramon, and Dublin and II in Castro Valley, Saratoga, Danville, Vallejo, Pleasanton, California.
O: 23DEC2025 08:11:11 37.7N 122.0W MD=2.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 23DEC2025 08:11:11 37.7N 122.0W MD=2.7 NEIC SAN FRANCISCO BAY AREA, CALIF.
O: 23DEC2025 08:23:42 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 4.0 in Northern Nevada was felt with intensity up to II-III in the area(s) of Northern Nevada in Carson City.
This epicenter is located at 103 degrees from central Philippines and at the fifth node
(72 degrees) from Hokkaido, Japan and may have been promoted by energy
from those sources.
O: 24DEC2025 03:50:09 41.2N 116.7W ML=4.0 EMSC NEVADA
NEIC reported an earthquake of M 4.5 in Valparaiso, Chile was felt with intensity up to II-III in the area(s) of Valparaiso, Chile with IV in La Ligua and III in Villa Alemana, Buin, Santiago and Vina del Mar.
O: 24DEC2025 01:05:20 32.4S 71.4W MW=4.5 EMSC VALPARAISO, CHILE
EMSC reported an earthquake of M 4.1 in Antofagasta, Chile was felt with intensity up to IV in the area(s) of Antofagasta, Chile at Calama.
This earthquake occurred near local solar midnight at a latitude which
is sub-solar on December 24 and may have been promoted by tidal stresses.
This epicenter is located at 143-144 degrees from Honshu, Japan and from Tropical Cyclone
Grant and may also have been promoted by energy from those sources.
O: 24DEC2025 06:10:10 22.6S 69.1W MB=4.3 EMSC ANTOFAGASTA, CHILE
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-24 00:00 UT 12.1S 98.2E 50 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 50 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 82W - is in the area north Panama, eastern Costa Rica and east of Central America where enhanced antipodal activity is possible as this storm moves to the west. It will be antipodal to El Salvador and Costa Rica around December 27, the most likely time for a significant regional earthquake.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 23, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0945 1021 1140 C4.9 (December 24, 2025) 1.4E-02
Taiwan M 6.0 09:47 UT
Chiapas M 4.3 10:00 UT
El Salvador M 4.1 10:08 UT
Andreanof Is. 10:57 UT
Mozambique M 3.0 10:57 UT
Fiji M 4.5 11:34 UT
5700 0003 0011 0017 C1.2 (December 23, 2025) 9.9E-04
5710 0137 0150 0202 C1.6 (December 23, 2025) 2.2E-03
5730 0916 0924 0933 C1.2 (December 23, 2025) 1.2E-03
Baja, Southern California M 3.2, 2.1 09:14-09:19 UT
Chiapas M 4.1 09:19 UT
5740 0945 0956 1004 C1.5 (December 23, 2025) 1.7E-03
Honshu M 5.2 09:44 UT
New Guinea M 5.2 09:55 UT
Hawaii M 3.5 09:57 UT
5750 1520 1529 1544 C1.1 (December 23, 2025) 1.6E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 24-25 unsettled December 26. Solar M-flare chance: 30% X-class: 5% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 21 42 14 15:00 6 106 142
A moderate G1 geomagnetic storm occurred on December 24 beginning around 10:00 UT at
high latitudes with K-index of 6. Some enhanced seismicity is possible with
this storm including events near the International Date Line (IDL) and the
Greenwich Meridian in the first hours after the commencement of this storm.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 23, 2025
Notable earthquakes and events:
The strongest geomagnetic storm of December 22, was a minor G1 with Kp reaching 5
beginning about 14:10 UT. High latitude geomagnetic storm reached Kp of 7 around
1400-1700 UT with A of 53, the second strongest storm in the past month at high latitudes.
An odd geomagnetic storm? occurred today about 09:45-10:00 UT (December 23). Spaceweatherlive.com
Described this as:
"Some kind of disturbance (Sneaky CME?) has arrived at earth. ... Expect at least
minor G1 geomagnetic conditions in the hours ahead if these conditions persist." (December 23, 2025)
This was associated with a C1.4 solar flare with the following SWPC parameters:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0945 0956 1004 C1.5 (December 23, 2025) 1.7E-03
Honshu M 5.2 09:44 UT
New Guinea M 5.2 09:55 UT
Hawaii M 3.5 09:57 UT
Earthquake of M 5.2 occurred in this period of fifteen minutes in Honshu, Japan and in
Eastern New Guinea with an M 3.5 in Hawaii as well.
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-21, 2025)
Mid-day on UT December 22, 2025 an M 6.5 earthquake occurred in Papua, New Guinea.
NEIC reported it was felt with intensity VI in New Guinea at Kainantu, Eastern Highland, V in Mount Hagen, Western Highlands; V in Goroka and Kundiawa, Simbu and III in Port Moresby.
EMSC reported moderate to strong shaking in Papua New Guinea at Law, Kerema, Port Moresby.
This is the strongest earthquake in the world since an M 6.6 and M 7.6 fourteen
days ago on December 8 in Hokkaido, Japan. It is also the strongest event in New Guinea
within about 200 km of this epicenter since an M 6.6 on October 7, 2025. At the time this
summary noted:
"The largest earthquake in the world was an M 6.6-6.7 in New Guinea at 146 East longitude near the maximum
expected tidal stress longitude. This was preceded by a strong swarm in the
eastern Caribbean with moderate quakes in Puerto Rico and the Virgin Islands (at 64-67 West longitude).
A swarm of events with magnitude up to M 5.1 also occurred off the coast of
Honshu, Japan (at 144 East longitude) following an M 4.9 in the Leyte, Philippines
aftershock zone (at 124 East longitude) and an M 4.1 in the Bonin Islands,
Japan (at 144 East longitude). These and other events today probably
were promoted by tidal stresses associated with today's super (full) moon.
The strongest earthquake in the world today was an M 6.6-6.7 in Papua New Guinea
east of Indonesia. NEIC reported it was felt in Papua New Guinea with maximum intensity VI in the Eastern Highlands at Kainantu and IV in Goroka, and Mount Hagen and V in the Morobe area at Lae, Wau and in the national Capital at Port Moresby with IV. Also felt with III in the north Solomons at Panguna and II in Balimo, Fly River and Kundiawa, Simbu, Papua New Guinea.
EMSC reported strong shaking in Papua New Guinea at Lae, Popondetta, Port Moresby.
This is the strongest earthquake within about 200 km of this epicenter since
a pair of events of M 6.7 and M 6.9 on October 7, 2023, exactly two years ago today. At the time this
summary noted:
"The strongest earthquake in the world today was an M 6.9 in Papua New Guinea.
It was followed by an M 6.7 and several moderate events of M>=5.
An M 5.1 aftershock was felt in Madang and Port Moresby, Papua New Guinea.
Other events in the series were not initially given intensities by NEIC however some felt data
comes from Madang, PNG. No tsunami was reported as this epicenter is inland near
the coast.
...
The earthquakes in New Guinea coincided with a moderate solar flare (#5480)
and may have been promoted by SFE associated with that flare.
...
An M 7.0 occurred about 350 km north of today's epicenter on April 2, 2023.
At the time this summary noted:
"The last earthquake of M>=6 in this area of Papua was an M 6.0 on January 18, 2020.
but no earthquake larger size than this have been recorded in this area since
an M 6.7 on January 10, 2002. ... This epicenter is at 103 degrees from the mainshocks in
Turkey and was probably promoted by energy from those sources." (February 9, 2023, April 2, 2023, October 7, 2023)
Today's event occurred shortly after the full moon arrived with maximum stress
in this area and near the geomagnetic equator.
A foreshock of M 4.9 south of this epicenter occurred earlier in the day. NEIC reported it
was felt with intensity III in Port Moresby, Papua New Guinea.
This earthquake may have also been promoted by SFE from a moderately strong
solar flare as it occurred at the beginning of that C5.6 flare. Preliminary
data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1100 1129 1134 C5.6 (October 7, 2025) 2.5E-03*
Papua New Guinea M 6.6 11:05 UT
Hindu Kush M 5.1 11:35 UT
Central California M 2.3 11:19 UT" (October 7, 2025)
Like that event of October 7, 2025, today's event in New Guinea was also
closely associated with a soli-lunar alignment coming a day after the
new moon of December 20, 2025. It also occurred near the longitude
of maximum tidal stress with that alignment as noted in previous issues
of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-21, 2025)
Readers may note that this longitude also saw a major swarm in the past
two days in the Kuril Islands and an M 4.6 in the Mariana Islands today.
More as this progression continues. Today's earthquake in New Guinea
occurred at the commencement of a G1 (kp5) geomagnetic storm near the
geomagnetic equator and may also have been promoted by geomagnetic
effects associated with the shock at the beginning of that storm one of the
strongest in the past month. A similar storm appears to be beginning
at high latitude around 10:00 UT on December 23 according to SWPC data.
An M 5.2 earthquake occurred at the start of this more recent event
as a regional aftershock in New Guinea at 09:56 UT (December 23).
This epicenter is at the sixth node (60 degrees) from Kamchatka and at the
eighth node (45 degrees) from Honshu, Tropical Cyclone Grant, and the Hokkaido/Kuril area and may
have been promoted by energy from those sources.
O: 22DEC2025 10:31:27 5.8S 145.5E MB=6.4 EMSC EASTERN NEW GUINEA REG., P.N.G
O: 22DEC2025 10:31:27 5.8S 145.5E MB=6.5 NEIC EASTERN NEW GUINEA REG., P.N.G
The earthquake in New Guinea appears to be consistent with the long-rnage
forecasts in this summary of November 30, 2025 as noted at the end of November
as:
"Some have wondered if the recent long quiet period in global seismicity will
be followed by a major global earthquake soon. Historical data suggests
about 30% chance of an earthquake in the world of M>=7.4 in the next month
on the basis of the 25 most prolonged global quiet periods of the past 35 years
as previously published in this summary. The most likely dates of such events
are 15-17 days after November 27, 2025 - when the quiet ended - and 21-22 days
after. This translates to a higher than likely probability of such a major
event in the next month within a day of December 13, 2025 and December 19, 2025" (November 30, 2025)
This epicenter is located at 107 degrees from Tropical Cyclone Grant and
may have been promoted by energy from that source.
NEIC reported an earthquake of M 3.3-3.5 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii at Captain Cook, Naalehu and Kailua Kona.
O: 23DEC2025 09:56:57 19.2N 155.5W ML=3.5 EMSC ISLAND OF HAWAII, HAWAII
NEIC reported an earthquake of M 5.2 South of Honshu, Japan was felt with intensity up to II-III in the area(s) of South of Honshu, Japan in Fujisawa, Kanagawa.
EMSC reported light shaking in Tokyo and Urayasu, Japan.
This epicenter is near the sixth node (60 degrees) from Tropical Cyclone Grant and from
Yukon, Canada and may have been promoted by energy from those sources.
O: 23DEC2025 09:44:21 33.1N 137.8E MW=5.2 EMSC NEAR S. COAST OF HONSHU,
Earthquakes also continued today in the eastern San Francisco, California area on the
northern Calaveras fault. The strongest of today's events included an M 2.7 which
occurred within a minute of local solar midnight and was probably promoted
by tidal and/or geomagnetic stresses which maximize near this time of day.
NEIC reported these earthquakes were felt with intensity up to III in San Ramon, and Dublin and II in Castro Valley, Saratoga, Danville, Vallejo, Pleasanton, California.
O: 22DEC2025 18:03:04 37.7N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 23DEC2025 08:11:11 37.7N 121.9W MD=2.7 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 22DEC2025 21:41:07 37.8N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 22DEC2025 23:00:50 37.8N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 23DEC2025 00:25:06 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 23DEC2025 08:23:42 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 2.9 in Southern California east of Los Angeles was felt with intensity up to II-III in the area(s) of Southern California east of Los Angeles with III in Big Bear Lake, and II in Lancaster, Apple Valley, Big Bear City and Yucaipa.
O: 23DEC2025 08:32:53 34.2N 116.9W ML=2.8 EMSC SOUTHERN CALIFORNIA
O: 23DEC2025 08:32:53 34.2N 116.9W ML=2.9 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 2.6 in Northern California was felt with intensity up to II-III in the area(s) of Northern California at Portola.
O: 23DEC2025 08:11:29 39.9N 120.6W MD=2.5 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.3 in Central California south of San Francisco was felt with intensity up to II-III in the area(s) of in Central California south of San Francisco in Carmel, Paicines with III and II in Carmel Valley, Marina, and Hollister.
O: 22DEC2025 23:32:28 36.7N 121.3W ML=3.2 EMSC CENTRAL CALIFORNIA
O: 22DEC2025 23:32:28 36.7N 121.3W ML=3.3 NEIC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 3.2 in Kenai, Alaska was felt with intensity up to II-III in the area(s) of Kenai, Alaska in Anchorage and Eagle River.
O: 22DEC2025 22:45:13 60.9N 150.6W ML=3.2 EMSC KENAI PENINSULA, ALASKA
NEIC reported an earthquake of M 4.6 in the Shanxi-Hebei region of NE China was felt with intensity up to II-III in the area(s) of the Shanxi-Hebei region of NE China with III in Mentougou, Beijing.
This is an unusual epicenter for an event of M>=4.5. The last earthquake
within about 200 km of this epicenter in northeastern China with M>=4.6
was recorded by NEIC as an M 4.7 on October 2, 2022 and before that an M 4.6 on February 12, 2018.
The last earthquake in the area of M>=5 was an M 5.3 on November 1, 1999, the largest
earthquake in this area in the past 30 years. At the time of the M 4.7
in October, 2022 this summary noted:
"NEIC reported this earthquake of M 4.7 in Eastern China was felt with intensity II-III in the area(s) of Eastern China in Shijiazhuang, Hebei (IV) and Taiyuan, Shanxi, China." (October 2, 2022)
This epicenter in China is near the sixth node from Yukon, Canada and the seventh
node from Cyclone Grant and may have been promoted by energy from those sources.
Forecast 178222 had expected this event within about 100 km of this epicenter
was likely around December 22.
O: 22DEC2025 12:31:20 39.4N 114.4E MB=4.6 EMSC SHANXI-HEBEI BORDER REG, CHINA
P: 22DEC2025 178222 39.0N 116.0E 3.5-4.9 AAAAA So. China
EMSC reported an earthquake of M 5.1 in the Caspian Sea was felt with intensity up to IV in the area(s) of the Caspian Sea in Turkmenbasy, Turkmenistan, in Azeraijan at Neft Daslari, Baku, Badamdar, Langarud, Kyakhulay, Russia, Amol, Iran.
This epicenter is at the fifth node (72 degrees) from Tropical Cyclone Grant and from
Mindanao, Philippines and may have been promoted by energy from those sources.
The last earthquake within about 250 km of of this event in the Caspian Sea
with M>=5.1 was recorded by NEIC as an M 5.4 on December 7, 2023 - an aftershock of an M 5.4 on July 3, 2023.
The only event of significantly larger magnitude in the area in the pst 35 years was an M 6.8 and M 6.5 on
November 26, 2000. At the time of the event in December 2023 this summary noted:
The strongest earthquake felt in the world today was an M 5.4 in Azerbaijan.
EMSC reported it was felt with moderate to strong intensity in Azerbaijan at Sumqayit, Corat, Saray, Ceyranbatan, Nardaran, Digah, Mastaga, Khirdalan, Bilajari, Baku, Khodzhi-Gasan, Biny Selo, Bakixanov, Qaracuxur, Khacmaz, Lobatan, Korgoz, Qusar, Sheki, and in Russia at Izerbash, Makhachkala, Kyakhulay, Leninkent, and in Shevchenko, Kazakhstan.
No events of M>=5.5 have hit Azerbaijan in at least four years. The last earthquake of equal or greater magnitude in Azerbaijan was an M 5.4 on
July 3, 2023. At the time this summary noted:
"An M 5.4 was widely felt today in the area of the Caspian Sea. NEIC reported it was felt with maximum magnitude IV in Azerbaijan at Siyazan, Quba, Qonaqkend, and in Dagestan, Russia at Derbent, Usukhchay with lesser intensity II-III in Azerbaijan at Sumqayit, Haci Zeynalabdin, Qusar and in Russia at Khazar.
The last earthquake with greater magnitude in Azerbaijan or the Caspian Sea
was an M 5.5 on June 7, 2014. At the time this summary noted in this regard:
"A moderately strong earthquake also hit the region of Azerbaijan near the Caspian Sea today with M 5.6.
EMSC reported this earthquake was felt for about 30 seconds in Baku, Azerbaijan.
NEIC reported intensity III in Xocasan and Corat, Azerbaijan and Tehran, Iran.
The last earthquake of M>=5.5 within 200 km of this epicenter occurred as an M 6.5
on November 25, 2000 with M 6.5-6.8. No other events of M>5.6 have hit in this
area in the past 25 years." (June 7, 2014)
Today's event occurred near local solar midnight and may have been promoted
by strong tidal stresses associated with today's full moon" (July 3, 2023, December 7, 2023)
Forecast 178248 had expected this event within about 100 km was likely around
December 23, 2025.
O: 23DEC2025 04:32:30 40.8N 51.9E MB=5.1 EMSC CASPIAN SEA, OFFSHR TURKMENIST
P: 23DEC2025 178248 40.0N 52.0E 4.0-5.5 AAAAA Kazakhstan
EMSC reported an earthquake of M 4.3 in Northern Mindanao, Philippines was felt with intensity up to IV in the area(s) of Northern Mindanao, Philippines in Dauin and Valencia, Dumaguete City, Negros Oriental.
O: 22DEC2025 15:42:41 9.3N 123.1E ML=4.0 EMSC NEGROS- CEBU REG, PHILIPPINES
EMSC reported an earthquake of M 4.0 in Laos was felt with intensity up to IV in the area(s) of Laos in Tachilek, Myanmar.
O: 22DEC2025 15:45:59 21.3N 101.7E MB=4.3 EMSC CHINA-LAOS BORDER REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE GRANT (09S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC GRANT 2025-12-23 00:00 UT 12.6S 100.0E 50 kts South of Sumatra
Tropical Cyclone Grant (09S) continued today in the region south of Sumatra winds up to 50 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 80W - is in the area north of Colombia and Panama and east of Central America where enhanced antipodal activity is possible as this storm moves to the west.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 22, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0945 0956 1004 C1.5 (December 23, 2025) 1.7E-03
Honshu M 5.2 09:44 UT
New Guinea M 5.2 09:55 UT
Hawaii M 3.5 09:57 UT
5610 0022 0030 0034 C2.3 (December 22, 2025) 1.5E-03
5620 0104 0115 0120 C1.6 (December 22, 2025) 1.4E-03
South Sandwich Is. M 4.6 01:08 UT
Philippine Is. M 4.6 01:14 UT
5650 0840 0846 0852 C2.0 (December 22, 2025) 1.8E-03
Northern Gulf of California M 3.4 08:49 UT M 3.5 08:52 UT
5670 0852 0914 0928 C2.8 (December 22, 2025) 5.6E-03
Northern Gulf of California M 3.5 08:52 UT
Baja California M 3.2, 3.2, 3.0, 3.0 09:21-09:29 UT
Papua New Guinea M 6.5 10:31 UT
5690 2221 2231 2256 C8.6 (December 22, 2025) 1.3E-02
Reykjanes Ridge M 4.5 22:29 UT
San Francisco M 2.2 23:00 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms December 23 active December 24-25. Solar M-flare chance: 30% X-class: 5% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 25 53 17 17:00 7 80 133
The strongest geomagnetic storm of December 22, however was a minor G1 with Kp reaching 5
beginning about 14:10 UT. High latitude geomagnetic storm reached Kp of 7 around
1400-1700 UT with A of 53, the second strongest storm in the past month at high latitudes.
An odd geomagnetic storm? occurred today about 09:45-10:00 UT (December 23). Spaceweatherlive.com
described this as:
"Some kind of disturbance (Sneaky CME?) has arrived at earth. ... Expect at least
minor G1 geomagnetic conditions in the hours ahead if these conditions persist." (December 23, 2025)
This was associated with a C1.4 solar flare with the following SWPC parameters:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0945 0956 1004 C1.5 (December 23, 2025) 1.7E-03
Honshu M 5.2 09:44 UT
New Guinea M 5.2 09:55 UT
Hawaii M 3.5 09:57 UT
Earthquake of M 5.2 occurred in this period of fifteen minutes in Honshu, Japan and in
Eastern New Guinea with an M 3.5 in Hawaii as well.
A strong Gamma Ray Burst was recorded by SWIFT on December 21, 2025 at 05:24:31 UT (#251221A). A preliminary UVOT Magnitude of V>19.6 was assigned to this GRB.
An earthquake of M 5.2 in New Britain accompanied this GRB at 05:25 UT.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacan, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 22, 2025
Notable earthquakes and events:
A moderately strong geomagnetic storm occurred on December 21, 2025 at high latitudes.
This storm register A at high latitudes of 50 the third largest of the past month with K-index of 7 about 19:00 UT (the first K-index of 7 since November 27, 2025).
Planetary K-index reached 5 near 00:00 UT on December 22, Incoming partical density with this stromed
peaked around 10:52-11:15 UT on December 22, 2025 - the most likely time for a triggered earthquake. This type of sudden
commencement geomagnetic storm (which apparently began 22:00-23:00 UT on December 21) can enhance seismicity at high latitudes
as well as near the geomagnetic equator as it ensues. This could mean
a strong earthquake near the equator most likely near 150 E longitude,
a longitude band stressed in the new moon alignment of December 20, 2025
as reported in this summary:
"... One of the largest of these - an M 5.1 in the Kurils occurred
within several minutes of local solar noon and was probably promoted
by tidal stresses associated with today's new moon as discussed in
the previous issue of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-21, 2025)
UPDATE:
Mid-day on UT December 22, 2025 an M 6.5 earthquake occurred in Papua, New Guinea.
NEIC reported it was felt with intensity VI in New Guinea at Kainantu, Eastern Highland, V in Mount Hagen, Western Highlands; V in Goroka and Kundiawa, Simbu and III in Port Moresby.
EMSC reported moderate to strong shaking in Papua New Guinea at Law, Kerema, Port Moresby.
This is the strongest earthquake in the world since an M 6.6 and M 7.6 fourteen
days ago on December 8 in Hokkaido, Japan. It is also the strongest event in New Guinea
within about 200 km of this epicenter since an M 6.6 on October 7, 2025. At the time this
summary noted:
"The largest earthquake in the world was an M 6.6-6.7 in New Guinea at 146 East longitude near the maximum
expected tidal stress longitude. This was preceded by a strong swarm in the
eastern Caribbean with moderate quakes in Puerto Rico and the Virgin Islands (at 64-67 West longitude).
A swarm of events with magnitude up to M 5.1 also occurred off the coast of
Honshu, Japan (at 144 East longitude) following an M 4.9 in the Leyte, Philippines
aftershock zone (at 124 East longitude) and an M 4.1 in the Bonin Islands,
Japan (at 144 East longitude). These and other events today probably
were promoted by tidal stresses associated with today's super (full) moon.
The strongest earthquake in the world today was an M 6.6-6.7 in Papua New Guinea
east of Indonesia. NEIC reported it was felt in Papua New Guinea with maximum intensity VI in the Eastern Highlands at Kainantu and IV in Goroka, and Mount Hagen and V in the Morobe area at Lae, Wau and in the national Capital at Port Moresby with IV. Also felt with III in the north Solomons at Panguna and II in Balimo, Fly River and Kundiawa, Simbu, Papua New Guinea.
EMSC reported strong shaking in Papua New Guinea at Lae, Popondetta, Port Moresby.
This is the strongest earthquake within about 200 km of this epicenter since
a pair of events of M 6.7 and M 6.9 on October 7, 2023, exactly two years ago today. At the time this
summary noted:
"The strongest earthquake in the world today was an M 6.9 in Papua New Guinea.
It was followed by an M 6.7 and several moderate events of M>=5.
An M 5.1 aftershock was felt in Madang and Port Moresby, Papua New Guinea.
Other events in the series were not initially given intensities by NEIC however some felt data
comes from Madang, PNG. No tsunami was reported as this epicenter is inland near
the coast.
...
The earthquakes in New Guinea coincided with a moderate solar flare (#5480)
and may have been promoted by SFE associated with that flare.
...
An M 7.0 occurred about 350 km north of today's epicenter on April 2, 2023.
At the time this summary noted:
"The last earthquake of M>=6 in this area of Papua was an M 6.0 on January 18, 2020.
but no earthquake larger size than this have been recorded in this area since
an M 6.7 on January 10, 2002. ... This epicenter is at 103 degrees from the mainshocks in
Turkey and was probably promoted by energy from those sources." (February 9, 2023, April 2, 2023, October 7, 2023)
Today's event occurred shortly after the full moon arrived with maximum stress
in this area and near the geomagnetic equator.
A foreshock of M 4.9 south of this epiceter occurred earlier in the day. NEIC reported it
was felt iwth intensity III in Port Moresby, Papaa New Guinea.
This earthquake may have also been promoted by SFE from a moderately strong
solar flare as it occurred at the beginning of that C5.6 flare. Preliminary
data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1100 1129 1134 C5.6 (October 7, 2025) 2.5E-03*
Papua New Guinea M 6.6 11:05 UT
Hindu Kush M 5.1 11:35 UT
Central California M 2.3 11:19 UT" (October 7, 2025)
Like that event of October 7, 2025, today's event in New Guinea was also
closely associated with a soli-lunar alignment coming a day after the
new moon of December 20, 2025. It also occurred near the longitude
of maximum tidal stress with that alignment as noted in previous issues
of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-21, 2025)
Readers may note that this longitude also saw a major swarm in the past
two days in the Kuril Islands and an M 4.6 in the Mariana Islands today.
More as this progression continues.
This epicenter is at the sixth node (60 degrees) from Kamchatka and at the
eighth node (45 degrees) from Honshu and the Hokkaido/Kuril area and may
have been promoted by energy from those sources.
O: 22DEC2025 10:31:27 5.8S 145.5E MB=6.4 EMSC EASTERN NEW GUINEA REG., P.N.G
NEIC reported an earthquake of M 4.6 in Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Mindanao, Philippines in Bislig, Caraga.
Ths event was an aftershock of an an M 5.6 in Mindanao earlier in the day.
NEIC reported that event with intensity up to V in the epicentral area.
This epicenter is at the seventh node from Kamchatka and may have been promoted
by energy from that sources.
O: 21DEC2025 17:53:58 8.4N 127.5E MW=5.6 EMSC PHILIPPINE ISLANDS REGION
O: 21DEC2025 23:11:21 7.0N 126.7E ML=4.0 EMSC MINDANAO, PHILIPPINES
O: 22DEC2025 01:14:13 8.4N 127.6E mb=4.6 EMSC PHILIPPINE ISLANDS REGION
NEIC reported an earthquake of M 2.9 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Fortuna.
NEIC reported an earthquake of M 3.4 in Central California was felt with intensity up to II-III in the area(s) of Central California in Hollister, Salinas, San Jose, Gardnerville, Nevada.
O: 21DEC2025 20:40:49 36.8N 121.4W ML=3.4 EMSC CENTRAL CALIFORNIA
O: 21DEC2025 22:05:39 36.8N 121.4W MD=2.1 EMSC CENTRAL CALIFORNIA
O: 21DEC2025 23:03:32 36.8N 121.4W MD=2.6 EMSC CENTRAL CALIFORNIA
The strongest earthquakes in the U.S. or Canada today occurred in the volcanic
area off the coast of Oregon with M 4.3 and M 4.5. They were not reported
felt on the mainland. These are located in the area of the Axial Volcano
which is expected to erupt soon. The larger event of M 4.5 occurred near
local solar midnight and may have been promoted by tidal stresses with
the new moon of October 20. The last earthquake of M>=4.5 within about
200 km of today's epicenter was an M 5.4 nearly two months ago on October 29, 2025and prior to that an M 5.1 and 5.9
on September 26-27, 2025. At the time this summary noted:
"The last earthquakes with M>=5.7 off the coast of Oregon occurred on June 4, 2021 (M 5.9) and
December 8, 2021 (M 5.8). This event also followed a full moon and was likely
promoted by tidal stresses associated with that alignment as explained in
this summary at the time:
"A strong series of earthquakes occurred off the coast of Oregon today at 120-130 West longitude. These events were reported lightly felt on the coast of Oregon including at Waldport, Eugene and Beaverton.
The largest of these was M 5.8 which was felt with intensity II-III in Oregon in Depoe Bay, Newport, Florence, Waldport, Hammond, Tualatin, Medford, Cloverdale, Seaside, Sheridan, Forest Grove, Springfield, Portland and as far as southern Washington State.
Other moderately large events of M 5.5, 5.5, 5.5, 5.5, 5.8, 5.3 ... also were recorded in this series.
The last earthquakes of M>=5.8 in this area off the coast of Oregon occurred in August and September, 2019
with M 6.3 and 5.9 and as an M 6.2 on August 22, 2018 and an M 5.9 on August 22, 2018. The
M 6.3 on August 29, 2019 is the strongest event in this area in the past 30 years.
Today's activity appears to be occurring the the volcanic vents off the coast
of Oregon. It is likely that this series was promoted by high tidal stresses associated
with the new moon/eclipse of December 4." (December 8, 2021, March 27, 2024, September 26, 2025)
This epicenter is near the eighth node from Kamchatka and the sixth node
from Honshu, Japan and may have been promoted by energy from those sources.
O: 21DEC2025 09:57:16 43.8N 127.9W MB=4.5 EMSC OFF COAST OF OREGON
O: 20DEC2025 14:05:07 43.9N 129.0W mb=4.3 EMSC OFF COAST OF OREGON
NEIC reported an earthquake of M 5.6 in Sulawesi, Indonesia was felt with intensity up to II-III in the area(s) of Sulawesi, Indonesia with II in Bitung.
O: 21DEC2025 12:21:46 1.4N 126.3E MW=5.6 EMSC MOLUCCA SEA
EMSC reported an earthquake of M 4.8 in Kazakhstan was felt with intensity up to IV in the area(s) of Kazakhstan in Turgen, Almaty, Pervomayka, Burunday.
This epicenter is at the seventh node from Kamchatka, the eighth node from Hokkaido
and the fifth node from Yukon, Canada and may have been promoted by energy
from those sources.
O: 21DEC2025 21:16:45 41.3N 78.8E MB=4.5 EMSC SOUTHERN XINJIANG, CHINA
SEISMIC EFFECTS OF TROPICAL CYCLONES
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 09S 2025-12-22 00:00 UT 12.0S 102.3E 50 kts South of Sumatra
Tropical Cyclone 09S continued today in the region south of Sumatra winds up to 50 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 78W - is in the area north of Colombia and Panama where enhanced antipodal activity is possible as this storm moves to the west.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 21, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5420 0214 0224 0232 C1.8 (December 21, 2025) 1.9E-03
San Francisco M 3.8 02:32 UT
5460 1154 1203 1211 C1.3 (December 21, 2025) 1.6E-03
Myanmar M 3.5 11:53 UT
5470 1211 1223 1229 C1.3 (December 21, 2025) 1.5E-03
Molucca Sea M 5.6 12:21 UT
5480 1247 1256 1301 C1.3 (December 21, 2025) 1.1E-03
Antofagasta M 4.2 12:47 UT
Balleny Is. M 5.0 13:12 UT
5500 1552 1558 1605 C1.4 (December 21, 2025) 1.1E-03
Izu Is. M 4.1 15:51 UT
5510 1647 1703 1727 C2.6 (December 21, 2025) 5.8E-03
Banda Sea M 4.3 17:02 UT
Idaho M 3.2 17:01 UT
Solomon Is. M 5.0 17:10 UT
5520 1812 1827 1836 M1.3 (December 21, 2025) 1.1E-02
Papua M 3.7 18:30 UT
5530 1929 1943 1951 C3.9 (December 21, 2025) 4.5E-03
Hokkaido M 4.3 19:33 UT
5540 1951 2000 2003 C6.1 (December 21, 2025) 3.9E-03
San Francisco CA, M 2.1 19:51 UT
5560 2016 2024 2032 C4.0 (December 21, 2025) 3.5E-03
5570 2051 2101 2107 C6.2 (December 21, 2025) 4.5E-03
Los Angeles M 2.0 20:54 UT
Xinjiang, China M 4.5 21:16 UT
5580 2157 2212 2219 C3.1 (December 21, 2025) 3.3E-03
5590 2228 2234 2237 C2.2 (December 21, 2025) 1.1E-03
Mariana Is. M 4.7 22:27 UT
Baja California M 3.2 22:30 UT
San Francisco CA, M 2.4 22:36 UT
5600 2325 2330 2334 C2.0 (December 21, 2025) 1.1E-03
Eastern Honshu M 4.5 23:33 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms December 22-23 active December 24. Solar M-flare chance: 25% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 27 50 20 19:00 7 85 124
A moderately strong geomagnetic storm occurred on December 21, 2025 at high latitudes.
This storm register A at high latitudes of 50 the third largest of the past month with K-index of 7 about 19:00 UT.
Planetary K-index reached 5 near 00:00 UT on December 22, This type of sudden
commencement geomagnetic storm can enhance seismicity at high latitudes
as well as near the geomagnetic equator as it ensues. This could mean
a strong earthquake near the equator most likely near 150 E longitude,
a longitude band stressed in the new moon alignment of December 20, 2025
as reported in this summary:
"One of the largest of these - an M 5.1 in the Kurils occurred
within several minutes of local solar noon and was probably promoted
by tidal stresses associated with today's new moon as discussed in
the previous issue of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-21, 2025)
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 21, 2025
Notable earthquakes and events:
A series of moderate earthquakes hit a number of regions of Japan today.
The strongest of this series occurred in the southern Kuril Islands about
200 km northeast of the current earthquakes in Hokkaido and northern
Honshu. One of the largest of these - an M 5.1 in the Kurils occurred
within several minutes of local solar noon and was probably promoted
by tidal stresses associated with today's new moon as discussed in
the previous issue of this summary:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-20, 2025)
O: 21DEC2025 06:58:48 34.8N 141.7E MB=5.1 EMSC OFF EAST COAST OF HONSHU,
O: 21DEC2025 01:29:02 40.8N 142.1E MW=5.4 EMSC NEAR EAST COAST OF HONSHU,
This earthquake was reported by NEIC to have been felt with intensity III in Misawa, Aomori, Japan.
O: 20DEC2025 21:30:30 41.1N 139.0E ML=4.2 EMSC HOKKAIDO, JAPAN REGION
The epicenters in Hokkaido and Honshu and the Kuril Islands area located
at the eighth node (45 degrees) from Yukon, Canada and may be promoted by
energy from that source.
O: 20DEC2025 12:58:54 42.7N 146.0E MB=5.2 EMSC OFF COAST OF HOKKAIDO, JAPAN
O: 20DEC2025 12:30:29 42.8N 146.0E Mw=5.3 EMSC HOKKAIDO, JAPAN REGION
O: 20DEC2025 12:33:56 42.8N 146.0E mb=5.1 EMSC OFF COAST OF HOKKAIDO, JAPAN
O: 21DEC2025 00:19:01 43.4N 147.9E MB=5.0 EMSC KURIL ISLANDS
O: 21DEC2025 04:03:38 43.5N 148.0E mb=5.1 EMSC KURIL ISLANDS
O: 21DEC2025 03:48:01 43.6N 147.8E Mw=5.2 EMSC KURIL ISLANDS
O: 21DEC2025 00:22:24 43.7N 147.8E mb=5.0 EMSC KURIL ISLANDS
O: 21DEC2025 00:26:01 43.7N 147.8E mb=4.9 EMSC KURIL ISLANDS
O: 21DEC2025 02:05:38 43.7N 147.7E mb=5.1 EMSC KURIL ISLANDS
O: 21DEC2025 04:47:10 43.7N 147.7E mb=4.7 EMSC KURIL ISLANDS
O: 21DEC2025 03:52:41 43.8N 147.9E mb=5.0 EMSC KURIL ISLANDS
O: 20DEC2025 23:46:33 43.9N 147.7E mb=4.8 EMSC KURIL ISLANDS
O: 21DEC2025 03:33:46 43.9N 147.7E mb=4.7 EMSC KURIL ISLANDS
The swarm near San Ramon east of San Francisco, California continued today.
The largest of today's events was an M 3.8. NEIC reported it was felt with
intensity IV in California at San Ramon, Dublin, Castro Valley, San Jose, Pleasanton, Danville, and II in Walnut Creek, San Anselmo and San Francisco.
Other events in the swarm were felt with intensity upt o IV in San Lorenzo, and III in Castro Valley, Dublin, San Ramon, Alamda, San
Bruno, Danville and II in Pleasanton, Hayward, and Morago. A widespread
power outage also occurred in San Francisco today but was probably not
related to the current elevated seismicity in that area. This summary
had reported last on this swarm in the previous issue as:
"The major swarm of light to moderate earthquakes in the eastern San Francisco
California Bay area today included several events of M 4.0 and M 3.8-3.9 which
were widely felt. NEIC reported more than 2000 people responded to them with
felt reports from each of these events. These included intensity V in California at Lafayette,
Hayward, IV in Brentwood, San Lorenzo, Oakland, San Jose, San Ramon, Vallejo, Union City, Alamo, Dublin, San Francisco and III in Millbrae, Fremont and Pleasanton among others." (December 20, 2025)
These epicenters are located at 102 degrees from central Philippines and at the
fifth node (72 degrees) from Hokkaido and may have been promoted by energy
from those sources.
O: 20DEC2025 16:10:32 37.7N 121.9W MD=2.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 21DEC2025 02:31:54 37.7N 121.9W Mw=3.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 21DEC2025 02:53:47 37.7N 121.9W MD=2.9 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 19:06:36 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 21DEC2025 02:36:35 37.8N 122.0W MD=2.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
Earthquakes also continued today near Ojai, California. An M 2.8 in this continuing
swarm was reported felt with intensity III in Ventura, Oak View and II in Ojai, California by NEIC.
O: 20DEC2025 12:44:52 34.4N 119.3W ML=2.4 EMSC SOUTHERN CALIFORNIA
O: 20DEC2025 12:47:12 34.4N 119.2W ML=2.8 EMSC SOUTHERN CALIFORNIA
O: 20DEC2025 14:01:43 34.4N 119.2W ML=2.9 EMSC GREATER LOS ANGELES AREA, CALIF.
O: 20DEC2025 17:19:09 34.4N 119.2W ML=2.4 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 5.2 in Bolivia was felt with intensity up to II-III in the area(s) of Bolivia in Iquique, Tarapaca, Chile.
O: 20DEC2025 20:30:24 20.1S 68.1W MW=5.2 EMSC POTOSI, BOLIVIA
The strongest earthquakes in the U.S. or Canada today occurred in the volcanic
area off the coast of Oregon with M 4.3 and M 4.5. They were not reported
felt on the mainland. These are located in the area of the Axial Volcano
which is expected to erupt soon. The larger event of M 4.5 occurred near
local solar midnight and may have been promoted by tidal stresses with
the new moon of October 20. The last earthquake of M>=4.5 within about
200 km of today's epicenter was an M 5.4 nearly two months ago on October 29, 2025and prior to that an M 5.1 and 5.9
on September 26-27, 2025. At the time this summary noted:
"The last earthquakes with M>=5.7 off the coast of Oregon occurred on June 4, 2021 (M 5.9) and
December 8, 2021 (M 5.8). This event also followed a full moon and was likely
promoted by tidal stresses associated with that alignment as explained in
this summary at the time:
"A strong series of earthquakes occurred off the coast of Oregon today at 120-130 West longitude. These events were reported lightly felt on the coast of Oregon including at Waldport, Eugene and Beaverton.
The largest of these was M 5.8 which was felt with intensity II-III in Oregon in Depoe Bay, Newport, Florence, Waldport, Hammond, Tualatin, Medford, Cloverdale, Seaside, Sheridan, Forest Grove, Springfield, Portland and as far as southern Washington State.
Other moderately large events of M 5.5, 5.5, 5.5, 5.5, 5.8, 5.3 ... also were recorded in this series.
The last earthquakes of M>=5.8 in this area off the coast of Oregon occurred in August and September, 2019
with M 6.3 and 5.9 and as an M 6.2 on August 22, 2018 and an M 5.9 on August 22, 2018. The
M 6.3 on August 29, 2019 is the strongest event in this area in the past 30 years.
Today's activity appears to be occurring the the volcanic vents off the coast
of Oregon. It is likely that this series was promoted by high tidal stresses associated
with the new moon/eclipse of December 4." (December 8, 2021, March 27, 2024, September 26, 2025)
This epicenter is near the eighth node from Kamchatka and the sixth node
from Honshu, Japan and may have been promoted by energy from those sources.
O: 21DEC2025 09:57:16 43.8N 127.9W MB=4.5 EMSC OFF COAST OF OREGON
O: 20DEC2025 14:05:07 43.9N 129.0W mb=4.3 EMSC OFF COAST OF OREGON
NEIC reported an earthquake of M 2.8 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Lakeport, Hopland and Ukiah.
O: 20DEC2025 10:56:13 38.9N 123.1W MD=2.6 EMSC NORTHERN CALIFORNIA
The largest earthquake recorded today was an M 5.5-5.6 in the Balleny Islands
South of New Zealand. This may have also been promoted by energy associated
with the new moon alignment as it occurred in an area which was near local
solar noon at the time of the alignment with maximum soli-lunar tides
with this new moon. It was not reported felt in this remote area.
An earthquake of M 3.3 preceded this event in Balleny Islands in Iceland
several hours earlier. That quake was nearly antipodal to the Balleny Islands.
This epicenter in the Balleny Islands is at 104-107 degrees from Honshu and
Hokkaido, Japan and may have been promoted by energy from major
earthquakes in those areas.
O: 20DEC2025 06:57:10 63.8S 172.6E MW=5.6 EMSC BALLENY ISLANDS REGION
O: 20DEC2025 10:25:04 63.8S 172.6E Mw=5.3 EMSC BALLENY ISLANDS REGION
EMSC reported an earthquake of M 4.8 in Tajikistan was felt with intensity up to IV in the area(s) of Tajikistan in Dushanbe.
EMSC reported an earthquake of M 5.2 in Bolivia was felt with intensity up to IV in the area(s) of Bolivia in Arequipa, Peru.
NEIC reported an earthquake of M 5.2 in Bolivia was felt with intensity up to II-III in the area(s) of Bolivia in Iquique, Tarapaca, Chile.
This epicenter was under near sub-solar conditions when it occurred.
This epicenter is located at 146 degrees from Hokkaido, Japan and may
have been promoted by energy from that source.
O: 20DEC2025 20:30:24 20.1S 68.1W MW=5.2 EMSC POTOSI, BOLIVIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 09S 2025-12-21 00:00 UT 12.4S 104.4E 55 kts South of Sumatra
Tropical Cyclone 09S continued today in the region south of Sumatra winds up to 55 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 76W - is in the area north of Colombia and Venezuela where enhanced antipodal activity is possible as this storm moves to the west.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 20, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5290 0059 0109 0113 C1.2 (December 20, 2025) 8.7E-04
Los Lagos, Chile M 4.0 01:05 UT
5330 0522 0534 0542 C1.3 (December 20, 2025) 1.6E-03
5370 0542 0546 0549 C1.2 (December 20, 2025) 6.4E-04
Mindanao M 4.6 05:52 UT
Fiji M 4.305:55 UT
San Francisco M 2.1 05:55 UT
5340 0608 0614 0623 C1.3 (December 20, 2025) 1.1E-03
Argentina M 4.7 06:29 UT
5350 0652 0706 0725 C1.4 (December 20, 2025) 2.6E-03
Balleny Is. M 5.6 06:57 UT
Oaxaca M 4.1 07:25 UT
5360 0736 0753 0815 M1.0 (December 20, 2025) 1.0E-02 *
Central California M 3.4 07:52 UT
5390 1915 1928 1939 C2.7 (December 20, 2025) 2.8E-03
5400 1948 1955 1958 C2.8 (December 20, 2025) 2.4E-03
Sulawesi M 4.0 19:50 UT
5430 1958 2005 2007 C3.1 (December 20, 2025) 2.1E-03
Peru M 4.1 20:11 UT
Bolivia M 5.2 20:30 UT
5410 2310 2320 2330 C1.3 (December 20, 2025) 1.5E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet December 21 minor storms December 22-23. Solar M-flare chance: 10% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 6 8 4 13:00 4 74 120
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 20, 2025
Notable earthquakes and events:
An unconfirmed geomagnetic pulse was recorded around 03:30 with peak around
04:10 UT on December 20, 2025. This was reported on social media and could
be in error. It involved data from the IceCube Neutrino Observatory at the south Pole
Station in Antarctica. At the same time a major swarm of light to moderate
earthquakes hit the East San Francisco Bay area of California - a swarm
which included two earthquakes of M 4.0. This series was widely felt in
the area near San Ramon, California. Both of these unusual events occurred
about an hour after the completion of the current new moon today. This
summary had noted seismic effects related to this new moon in previous issues as:
"The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands." (December 18-20, 2025)
The largest earthquake recorded today was an M 5.5-5.6 in the Balleny Islands
South of New Zealand. This may have also been promoted by energy associated
with the new moon alignment as it occurred in an area which was near local
solar noon at the time of the alignment with maximum soli-lunar tides
with this new moon. It was not reported felt in this remote area.
An earthquake of M 3.3 preceded this event in Balleny Islands in Iceland
several hours earlier. That quake was nearly antipodal to the Balleny Islands.
This epicenter in the Balleny Islands is at 104-107 degrees from Honshu and
Hokkaido, Japan and may have been promoted by energy from major
earthquakes in those areas.
O: 20DEC2025 06:57:10 63.8S 172.6E MW=5.6 EMSC BALLENY ISLANDS REGION
O: 20DEC2025 02:42:35 63.9N 19.2W ML=3.3 EMSC ICELAND
The major swarm of light to moderate earthquakes in the eastern San Francisco
California Bay area today included several events of M 4.0 and M 3.8-3.9 which
were widely felt. NEIC reported more than 2000 people responded to them with
felt reports from each of these events. These included intensity V in California at Lafayette,
Hayward, IV in Brentwood, San Lorenzo, Oakland, San Jose, San Ramon, Vallejo, Union City, Alamo, Dublin, San Francisco and III in Millbrae, Fremont and Pleasanton among others.
in December 17, 2025 this summary reported on these events in San Francisco
as:
"An earthquake of M 3.0 in the area of San Francisco Bay, California also coincided
with the above-mentioned solar flares. This earthquake was reported by NEIC
to have been felt with intensity III in Oakland, San Ramon, Alamo, San Leandro, Berkeley, , Walnut Creek, Dublin and Castro Valley and II in Alameda, Haywrd, Pleasanton, Danville, San Francisco, San Rafael, Stockton, Sunnyvale, Hayward and Livermore.
It continues a series of events near this epicenter which has been ongoing
for several weeks and could be precursory to a moderate to large regional
earthquake with origin near this epicenter. A major earthquake on this
portion of the Calaveras Fault is still considered unlikely at this time though." (December 17, 2025)
As this swarm began within about an hour of the new moon today, it is most
likely to have been promoted by tidal stresses with that event (see above).
The last swarm of events in this region of California with events of M>=4
occurred on September 22, 2025 with an event of M 4.3. At the time this summary
noted:
The new moon arrived today. Several unusual earthquakes accompanied it and were
probably promoted by tidal stresses associated with it and the now completed geomagnetic storm of mid-September.
The effects of this new moon and eclipse expected in the previous issue of
this summary were noted in the previous issue as:
"The new moon will arrive on September 21, 2025 at 19:54 UT. A partial solar eclipse will accompany this new moon with maximum eclipse near 19:41 UT covering about 85% of the sun with sub-solar point near 0N 118W. It will be visible in New Zealand, Antarctica and as far as the South Sandwich Islands with greatest eclipse near 60S 150E in the Macquarie Island region. Enhanced seismicity in this area is likely at this time as well as near the antipode near Iceland. Longitudes which are at local solar noon at this time are near 119W and those at local solar midnight near 61E. In the west these include western North America and portions of the East Pacific Rise and in the east portions of the central Indian Ocean and Central Asia near Hindu Kush, Iran, Pakistan and Afghanistan among others. These areas are most likely to see tidal triggering in the next week. A large earthquake is possible in this time and tidal triggering is not limited to these regions but is most likely near local solar noon or local solar midnight." (September 20-21, 2025)
For many readers, the most significant earthquake associated with this new moon and
solar eclipse was an M 4.3 in the area of San Francisco, California. NEIC reported
it was felt with intensity up to V in the San Francisco area with more than
22,000 people reporting felt effects to the USGS. Rather than list all the communities
affected by this earthquake readers are referred to the USGS website:
https://earthquake.usgs.gov/earthquakes/eventpage
The strongest felt reports came to NEIC from citizens in California with slight damage (VI) at Oakland, Berkeley; V in San Francisco, Alameda, Concord, Oakland, Emeryville, Berkeley, Portola Valley and IV in Pacifica, Redwood City, San Francisco, Alameda, Danville, Concord, Pleasant Hill, El Cerrito, Fairfield, Lafayette, Martinez, Moraga, Orinda, Pinole, San Leandro, Vallejo, Walnut Creek, Oakland, Berkeley, Albany, among others. It was was as far as 150 km from the epicenter.
Readers of this summary had been warned of the potential for enhanced
seismicity near this location in California with the new moon and solar
eclipse of September 21. For example in the previous issue it was noted:
"... seismicity is likely to rise in California through eastern Alaska in the
next several days (these areas are subsolar with today's new moon) ..." (September 20-22, 2025)
Today's earthquake of M 4.3 in San Francisco, California is the strongest
recorded within about 50 km of San Francisco since an M 4.5 two years ago on
October 15, 2019. At the time this summary noted:
"The activity in San Francisco began several hours before local solar midnight
and was probably promoted by strong tidal stresses associated with the full moon
...
The last event in the San Francisco Bay area within about 75 km of today's epicenter
which exceeded M 4.5 occurred on August 24, 2014 when an M 6.0 hit the Napa area.
The last within the San Francisco Bay area was an M 5.6 more than 11 years ago on October 31, 2007." (October 15, 2019, September 22, 2025)
(any similarity to today's situation is probably? coincidental? - Think timing,
location, new moon etc.)
These epicenters are located at 102 degrees from central Philippines and at the
fifth node (72 degrees) from Hokkaido and may have been promoted by energy
from those sources.
O: 19DEC2025 17:13:31 37.7N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:49:22 37.7N 121.9W Mw=3.6 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:56:09 37.7N 121.9W Mw=3.9 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:56:09 37.7N 121.9W Mw=4.0 NEIC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 04:06:31 37.7N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 04:10:00 37.7N 121.9W MD=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 04:36:57 37.7N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 05:55:47 37.7N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 06:01:47 37.7N 121.9W MD=2.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 19DEC2025 11:37:39 37.8N 121.9W MD=2.4 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:41:31 37.8N 121.9W MD=2.5 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:57:56 37.8N 121.9W ML=3.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 03:58:44 37.8N 122.0W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 20DEC2025 04:15:41 37.8N 121.9W MD=2.3 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 3.4 in Central California near San Lucas was felt with intensity up to II-III in the area(s) of King City with III and in Salinas and San Francisco with lesser intensity.
This event occurred within minutes of local solar midnight at the peak of the largest solar
flare of the past two days. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0736 0753 0815 M1.0 (December 20, 2025) 1.0E-02 *
Central California M 3.4 07:52 UT
This epicenter is located at 103 degrees from central Philippines and at the
fifth node (72 degrees) from Hokkaido and may have been promoted by energy
from those sources.
O: 20DEC2025 07:51:35 36.2N 120.9W ML=3.3 EMSC CENTRAL CALIFORNIA
O: 20DEC2025 07:51:35 36.2N 120.9W ML=3.5 NEIC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 2.7 in Washington State was felt with intensity up to II-III in the area(s) of Washington State in Chehalis and Port Orchard.
This epicenter is located at 101 degrees from central Philippines and at the fifth
node from Hokkaido and may have been promoted by energy from those sources.
O: 19DEC2025 23:29:54 46.5N 123.4W ML=2.6 EMSC WASHINGTON
NEIC reported an earthquake of M 5.1 in Ecuador was felt with intensity up to II-III in the area(s) of Ecuador with III in Latacunga, Cotopaxi, Quito, Pichincha and Archidona, Napo and II in Sangolqui.
This epicenter is at the sixth node (60 degrees) from the Drake Passage
and May have been promoted by energy from that source.
O: 19DEC2025 21:59:54 0.7S 78.0W MB=5.1 EMSC ECUADOR
NEIC reported an earthquake of M 2.6 in Southern California was felt with intensity up to II-III in the area(s) of Southern California in Big Bear City, California.
O: 19DEC2025 16:38:42 34.3N 116.8W ML=2.6 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.2 in Southern California was felt with intensity up to II-III in the area(s) of Southern California with III in Cathedral City, La Quinta, Mountain Center and II in Indio, Aguanga, Warner Springs, Escondido, Palm Desert, Palm Springs and Valley Center.
This epicenter is located at 103 degrees from the Drake Passage
and at the sixth node from Kamchatka and may have been promoted by energy
from those sources.
O: 19DEC2025 14:52:54 33.5N 116.5W ML=2.6 EMSC SOUTHERN CALIFORNIA
O: 19DEC2025 17:44:16 33.5N 116.5W ML=2.0 EMSC SOUTHERN CALIFORNIA
O: 19DEC2025 09:49:03 33.7N 116.8W ML=2.0 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 2.5 in eastern Los Angeles, California was felt with intensity up to II-III in the area(s) of eastern Los Angeles, California with III in Fontana, Riverside, Colton, Bloomington, and II in Rialto and Norco.
EMSC reported an earthquake of M 2.5 in eastern Los Angeles, California was felt with intensity up to IV in the area(s) of Southern California as a jolt in Bloomington, Sunnyslope, Highgrove, Eastvale, Riverside.
This earthquake occurred within a few minutes of local solar midnight
and was likely promoted by tidal stresses with the upcoming new moon.
This epicenter is located at 104-106 degrees from the Drake Passage and central Philippines
and at the sixth node from Kamchatka and may have been promoted by energy
from those sources.
O: 19DEC2025 07:54:18 34.1N 117.4W ML=2.5 EMSC GREATER LOS ANGELES AREA, CALI
An earthquake of M 3.9 also occurred in the northern Gulf of California today.
It was not reported felt in this area.
O: 19DEC2025 20:52:37 30.6N 114.3W ML=3.9 EMSC GULF OF CALIFORNIA
A series of events also occurred today in northern Baja California, Mexico
near the southern California border with M 3.1, 3.4 and 3.0 among others.
These events occurred within minutes of local solar noon and local solar
midnight and were probably promoted by tidal stresses with the new moon
today which maximize near this hour.
These epicenters are at 101 degrees from the Drake Passage and may have
been promoted by energy from that source.
O: 19DEC2025 08:02:41 31.3N 115.3W ML=3.1 EMSC BAJA CALIFORNIA, MEXICO
O: 19DEC2025 08:11:34 31.3N 115.4W ML=3.4 EMSC BAJA CALIFORNIA, MEXICO
O: 19DEC2025 20:28:17 31.4N 115.6W ML=3.0 EMSC BAJA CALIFORNIA, MEXICO
EMSC reported an earthquake of M 4.3 in Pakistan was felt with intensity up to IV in the area(s) of Pakistan in Attock City.
This epicenter is located near the sixth node (60 degrees) and the seventh
node (52 degrees) from recent major disturbances south of Java, in Kamchatka,
Hokkaido, and Central Philippines and may have been promoted by constructive
interference of energy from those sources.
O: 20DEC2025 04:37:17 33.8N 72.2E MB=4.2 EMSC PAKISTAN
SEISMIC EFFECTS OF TROPICAL CYCLONES
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 09S 2025-12-20 00:00 UT 12.0S 107.1E 55 kts South of Sumatra
Tropical Cyclone 09S continued today in the region south of Sumatra winds up to 55 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 73W - is in the area north of Colombia and Venezuela where enhanced antipodal activity is possible as it moves to the west.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 19, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0736 0753 0815 M1.0 (December 20, 2025) 1.0E-02 *
Central California M 3.4 07:52 UT
5210 0534 0543 0549 C1.9 (December 19, 2025) 1.4E-03
Afghanistan M 5.3 05:39 UT
Luzon M 4.2 05:33 UT
5220 0553 0558 0601 C1.3 (December 19, 2025) 7.0E-04
Chiapas M 4.1 05:51 UT
5230 0608 0620 0628 C1.7 (December 19, 2025) 1.7E-03
Afghanistan M 4.6 06:35 UT
5240 1314 1343 1358 C2.2 (December 19, 2025) 4.5E-03
Central Turkey M 4.2 13:19 UT
Maui, Hawaii M 2.9 13:37 UT
Southern Iran M 4.3 13:38 UT
5250 1535 1558 1608 M1.0 (December 19, 2025) 1.3E-02
5260 1704 1716 1724 C2.3 (December 19, 2025) 2.0E-03
San Francisco M 2.2 17:14 UT
5280 2215 2223 2231 C1.8 (December 19, 2025) 1.5E-03
Central California M 2.1 22:25 UT M 2.5 22:35 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 20 unsettled December 21 minor storms December 22. Solar M-flare chance: 5% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 6 4 4 02:00 2 33 118
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 19, 2025
Notable earthquakes and events:
A strong M 5.9 earthquake occurred in the area of Kamchatka today near local solar midnight.
NEIC reported it was likely felt with intensity up to V in Petropavlovsk-Kamchatsky, Russia but this was not verified.
EMSC reported it was widely felt in Kamchatka in Yelizovo, V ilyuchinsk, Paratunka, Severo-Kurilsk and Petropavlovsk-Kamchatsky.
This event is consistent with tidal triggering associated with the new
moon alignment early on December 20 as noted in this summary:
The new moon will arrive on December 20, 2025 at 01:43 UT. Longitudes which will be at local solar midnight at this time are near 25 West while those at local solar noon are near 155 East. These zones include the central Atlantic and Iceland and western Europe in the west (local solar midnight) and the Kamchatka, the Kuril Islands, Japan and portions of eastern Indonesia and the Vanuatu Islands in the east (local solar noon). These areas are the most likely to see tidal triggering in the next week. Such events often occur near local solar midnight and noon. A strong earthquake is considered likely with this new moon in the next several days with most likely probability in the northwestern Pacific rim including Kamchatka, Japan and the Kuril Islands.
Today's M 5.9 in Kamchatka is the strongest earthquake in Kamchatka within
about 200 km of this epicenter and in the aftershock zone of the series
that began in mid-July 2025 and included an M 8.8 on July 29, 2025 event in October since an M 6.0
more than a month-and-a-half ago on November 4, 2025. The series in early
November, 2025 in Kamchatka, like today's earthquake occurred with the alignment
of sun and moon in a full moon of November 5, 2025 which culminated while
Kamchatka was at local solar midnight. Other major milestones in the
Kamchatka sequence (as in the mid-July start and an M 7.8 on September 18, 2025) have also occurred near new and
full moons and were probably tidally enhanced.
Kamchatka is located at the seventh node (52 degrees) from Central Philippines
and may also have been promoted by energy from that area.
O: 18DEC2025 11:19:40 51.4N 159.9E MB=4.5 EMSC OFF EAST COAST OF KAMCHATKA
O: 18DEC2025 12:37:19 52.9N 159.8E Mw=5.9 EMSC OFF EAST COAST OF KAMCHATKA
O: 18DEC2025 23:25:43 53.1N 159.6E mb=4.3 EMSC NEAR EAST COAST OF KAMCHATKA
O: 18DEC2025 14:56:00 55.9N 163.0E mb=4.3 EMSC OFF EAST COAST OF KAMCHATKA
In the previous issue of this summary it had been noted:
"A moderate geomagnetic storm appears to be starting at high latitudes (kp 6) around 09:00 UT on December 18.
This could encourage seismicity in sub-solar sections and high latitudes. NOAA's GOES Magnetometer
shows a spike in geomagnetic field intensity near 07:10 UT which could indicate
the sudden commencement of this storm. Areas which could see immediate changes is
seismicity include Afghanistan and central Asia." (December 18, 2025)
The second strongest earthquake felt in the world today was an M 5.3 and M 5.0 aftershock
in Afghanistan in the Hindu Kush area. This earthquake was reported by EMSC
to have been felt with very strong intensity in Kunduz, Afghanistan and lesser
intensity in Afghanistan at Kabul, Mazar-e-Sharif, Qadis; in Islamabad, Pakistan and in Tirmiz, Uzbekistan where it terrifying; and in Dushanbe, Tajikistan. Light shaking was also felt in Uzbekistan at Yangi-Nishon Shahri, Samarkand, Tashkent, Salor and in .
These epicenters are at or near the sixth node (60 degrees) from central
Philippines, Kamchatka and Hokkaido and at the seventh node (52 degrees) from
the north geomagnetic pole and TC Bakung and may have been promoted by energy
from those sources.
O: 19DEC2025 05:39:10 36.3N 69.4E MW=5.3 EMSC HINDU KUSH REGION, AFGHANISTAN
O: 19DEC2025 06:35:02 36.6N 69.5E mb=4.4 EMSC HINDU KUSH REGION, AFGHANISTAN
A strong earthquake of M 5.7 occurred today in Fiji. It was not reported
felt in this remote area but NEIC estimaged intensity up to VII may have been felt in the epicentral area. This event occurred as remnants of Tropical Storm
08P were dissipating over this epicenter and today's event may have been
promoted by energy from this storm. This storm was last described
in this summary on December 16, 2025 as:
"TC 08P 2025-12-16 00:00 UT 15.1S 172.1E 45 kts Fiji
Tropical Cyclone 07P continued today in the region of Fiji with winds up to 45 kts. It could help promote moderate seismicity in Vanuatu and/or Fiji as it tracks south and east in this active seismic area. The antipode is at 15N 8W - is not a seismic active area." (December 16, 2025)
This epicenter is at the fifth node (72 degrees) from Kamchatka; the sixth node
(60 degrees) from central Philppines and 103 degrees from the North Geomagnetic
Pole and may have been promoted by energy from those sources.
O: 19DEC2025 05:00:19 15.7S 179.6W MW=5.7 EMSC FIJI REGION
NEIC reported an earthquake of M 4.8 in Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Mindanao, Philippines in Mawab, Southern Mindanao.
O: 18DEC2025 19:32:56 5.2N 126.8E ML=4.1 EMSC MINDANAO, PHILIPPINES
O: 18DEC2025 21:19:35 7.0N 127.1E mb=4.7 EMSC PHILIPPINE ISLANDS REGION
O: 19DEC2025 05:25:55 7.7N 126.7E mb=4.8 EMSC MINDANAO, PHILIPPINES
NEIC reported an earthquake of M 3.3 in Central Alaska was felt with intensity up to II-III in the area(s) of Central Alaska in Fairbanks, North Pole and Fort Wainwright.
NEIC reported an earthquake of M 3.6 in Central California was felt with intensity up to II-III in the area(s) of Central California in Ridgecrest.
This is a somewhat unusual earthquake for Central California. The last
event within about 50 km of this epicenter with M>=3.6 occurred on
October 6, 2024 with M 3.6 but the last event in the region occurred
more than 35 years years ago. This could be an important precursory
earthquake to a stronger event in the near future.
O: 18DEC2025 15:13:42 35.9N 116.9W MW=3.6 EMSC CENTRAL CALIFORNIA
O: 18DEC2025 15:28:30 35.9N 116.9W ML=2.1 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 5.0 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan with IV in Taipei and III in Hualien City, Hsinchu and II in Yunlin and Tainan Counties Taiwan.
O: 18DEC2025 11:32:50 24.1N 121.8E MB=5.0 EMSC TAIWAN
NEIC reported an earthquake of M 2.8 in Central California was felt with intensity up to II-III in the area(s) of Central California with III in Salinas, and II in San Mateo, Gilroy and Hollister.
NEIC reported an earthquake of M 2.5 in eastern Los Angeles, California was felt with intensity up to II-III in the area(s) of eastern Los Angeles, California with III in Fontana, Riverside, Colton, Bloomington, and II in Rialto and Norco.
EMSC reported an earthquake of M 2.5 in eastern Los Angeles, California was felt with intensity up to IV in the area(s) of Southern California as a jolt in Bloomington, Sunnyslope, Highgrove, Eastvale, Riverside.
This earthquake occurred within a few minutes of local solar midnight
and was likely promoted by tidal stresses with the upcoming new moon.
O: 19DEC2025 07:54:18 34.1N 117.4W ML=2.5 EMSC GREATER LOS ANGELES AREA, CALI
SEISMIC EFFECTS OF TROPICAL CYCLONES
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 09S 2025-12-19 00:00 UT 12.5S 108.9E 45 kts South of Sumatra
Tropical Cyclone 09S continued today in the region south of Sumatra winds up to 45 kts. It could continue to excite regional seismicity while south of Sumatra. The antipode is at 12N 71W - is in the area north of Colombia and Venezuela where enhanced antipodal activity is possible as it moves to the west.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 18, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5120 0002 0011 0014 C1.3 (December 18, 2025) 8.9E-04
Kuril Is. M 4.2 00:01 UT
5130 0305 0315 0331 C1.7 (December 18, 2025) 2.1E-03
Kamchatka M 4.5 03:11 UT
Quebec, Canada M 3.0 03:19 UT
Myanmar M 4.0 03:33 UT
5150 0744 0750 0756 C3.2 (December 18, 2025) 1.7E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 19-20 unsettled December 21. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 17 36 17 11:00 6 87 116
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 18, 2025
Notable earthquakes and events:
A moderate geomagnetic storm appears to be starting at high latitudes (kp 6) around 09:00 UT on December 18.
This could encourage seismicity in sub-solar sections and high latitudes. NOAA's GOES Magnetometer
shows a spike in geomagnetic field intensity near 07:10 UT which could indicate
the sudden commencemtne of this storm. Areas which could see immediate changes is
seismicity include Afghanistan and central Asia. Additional
enhancement could occur near regions at local solar midnight (western U.S and
Canada) within an hour or so of commencement.
Over the past several days, this summary has been following possible antipodal
seismic triggering from Tropical Cyclone Bakung (TC 07S) in the region of
Central America. This cyclone began after moving from about 7S 97E on December 11, 2025
into a full Tropical Cyclone on December 12-13 with the following parameters\
as described in this summary at the time:
"TC 07S 2025-12-12 00:00 UT 8.4S 97.3E 45 kts South of Sumatra
Tropical Cyclone 07S formed today in the region south of Sumatra winds up to 45 kts. It could help promote moderate seismicity as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 9N 83W - is in the area of Costa Rica. Some enhanced seismicity in Panama and Costa Rica is possible near 9N 83W as this cyclone tracks to the west over the next several days." (December 12-14, 2025)
While relatively moderate events in Central America of M 4.4-5.3 in Nicaragua
and M 4.4-4.7 in El Salvador appear to have been triggered by the passage of this
storm, no moderately large to large quakes have been associated with it - but
this has now changed. An earthquake south of Panama today of M 5.6-5.7 occurred
at a position antipodal to the start of Bakung with the following parameters:
O: 17DEC2025 23:07:47 7.0N 82.5W ML=5.6 EMSC SOUTH OF PANAMA
The occurrence of this event illustrates that some longer-term effects
associated with antipodal triggering are possible. NEIC reported this earthquake
was felt with intensity II in Panama at Boquete, Chiriqui.
EMSC reported moderate shaking in Central Panama in Bajo Boquete, Jaramillo.
At M 5.7 this is the strongest earthquake in the world today. The last earthquake
within about 200 km of this epicenter south of Panama with M>=5.7
occurred on July 14, 2025 with M 6.2. At the time this summary noted:
"The strongest earthquake in the world today was an M 6.2 in the region of Panama.
NEIC reported it was felt lightly in Boquete, Chiriqui, Panama and possibly in Costa Rica but was likely felt with intensity IV in the epicentral area.
This is the strongest earthquake in Panama within about 200 km of this epicenter
since an M 6.6 on January 7, 2015 and an M 6.3 on June 4, 2012." (July 14, 2025)
A foreshock of M 3.0 occurred three minutes before the mainshock about
50 km north of the mainshock epicenter.
This epicenter is near the third node (120 degrees) from Hokkaido; at 147 degrees
from Central Philippines and at 100 degrees from Kamchatka and may have
also been promoted by energy from those sources.
O: 17DEC2025 23:07:46 6.7N 82.6W MW=5.6 EMSC SOUTH OF PANAMA
O: 17DEC2025 23:07:46 6.7N 82.6W MW=5.7 ICR SOUTH OF PANAMA
O: 17DEC2025 23:04:32 7.2N 83.3W ML=3.0 EMSC OFF COAST OF COSTA RICA
O: 17DEC2025 23:23:06 7.5N 83.2W ML=3.5 EMSC OFF COAST OF COSTA RICA
NEIC reported an earthquake of M 2.8 in Central California was felt with intensity up to II-III in the area(s) of Central California with III in Salinas and II in Gilroy and Hollister.
This event which occurred near local solar midnight may have been triggered by a geomagnetic storm which began about the
same time.
O: 18DEC2025 09:52:39 36.8N 121.5W MD=2.7 EMSC CENTRAL CALIFORNIA
O: 18DEC2025 09:52:39 36.8N 121.5W MD=2.8 NEIC CENTRAL CALIFORNIA
O: 18DEC2025 09:53:31 36.8N 121.5W MD=2.1 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 5.5 in northern Philippines was felt with intensity up to II-III in the area(s) of northern Philippines th IV estimated near Basco, Philippines.
This epicenter is at the eighth node (45 degrees) from Kamchatka and may
have been promoted by energy from that source.
O: 18DEC2025 07:27:46 19.9N 121.4E MW=5.5 EMSC BABUYAN ISL REGION, PHILIPPINE
NEIC reported an earthquake of M 5.0 in Molucca Sea, Indonesia was felt with intensity up to II-III in the area(s) of Molucca Sea, Indonesia with III in Bitung, Sulawesi.
This epicenter is at the sixth node from Kamchatka; the fourth node from
Yukon, Canada and the 10th node from TC Bakung and may have been promoted
by energy from those sources.
O: 18DEC2025 05:30:19 1.4N 125.8E MB=5.0 EMSC MOLUCCA SEA
NEIC reported an earthquake of M 3.0 in Quebec, Canada was felt with intensity up to II-III in the area(s) of Quebec Canada with III in Saint-Alexandre, Saint-Pascal, Saint-Pacome and II in La Pocatiere.
EMSC reported moderate shaking in Quebec, Canada at Saint-Pacome and La Malbaie.
This epicenter is at 143 degrees from TC Bakung, and at the fifth node
(72 degrees) from Kamchatka and may have been promoted by energy from those
sources.
O: 18DEC2025 03:19:09 47.6N 69.8W ML=3.0 EMSC ST. LAWRENCE VALLEY REG., CANA
NEIC reported an earthquake of M 5.0 in Southern Vanuatu was felt with intensity up to II-III in the area(s) of Southern Vanuatu in Port Vila Shefa.
This epicenter is located at the fifth node (72 degrees) from Kamchatka and TC Bakung at the
the seventh node (52 degrees) from Leyte, Philippines and at the fourth node node (90 degrees)
from Yukon, Canada and may have been promoted by constructive interference
of energy from those sources.
O: 17DEC2025 22:30:07 18.5S 168.5E MW=5.0 EMSC VANUATU
NEIC reported an earthquake of M 5.4 in Samoa was felt with intensity up to II-III in the area(s) of Samoa in Alo Wallis and Futuna with intensity II.
This epicenter is located at the fifth node (72 degrees) from Kamchatka and at the
sixth node (60 degrees) from Mindanao and may have been promoted by energy
from those sources.
O: 17DEC2025 17:23:27 16.7S 177.3W MW=5.4 EMSC FIJI REGION
A moderately strong earthquake today also occurred as an M 5.7 in the South Sandwich Islands. It was not reported felt in this remote area.
This epicenter is located at 147 degrees from the Yukon, Canada event and near
the fourth node (90 degrees) from TC Bakung and may have been promoted by
energy from those sources.
O: 17DEC2025 17:05:59 58.8S 25.4W MW=5.7 EMSC SOUTH SANDWICH ISLANDS REGION
NEIC reported an earthquake of M 3.1 in Central California was felt with intensity up to II-III in the area(s) of Central California in Ranco Palos Verdes.
O: 17DEC2025 10:01:15 35.9N 117.7W ML=3.2 EMSC CENTRAL CALIFORNIA
O: 18DEC2025 00:22:46 35.0N 117.0W ML=2.0 EMSC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 4.0 in Sunda Strait, Indonesia was felt with intensity up to IV in the area(s) of Sunda Strait, Indonesia in Babakantonggoh.
This epicenter is at the sixth node (60 degrees) from Hokkaido and at 107 degrees
from Yukon, Canada and may have been promoted by energy from those sources.
It occurred within minutes of local solar noon and may also have been
promoted by tidal and/or geomagnetic stresses.
O: 18DEC2025 05:23:40 6.7S 105.5E ML=4.0 EMSC SUNDA STRAIT, INDONESIA
EMSC reported an earthquake of M 4.4 in Azores, Portugal was felt with intensity up to IV in the area(s) of Azores, Portugal at Fonte Bastardo, Porto Judeu, Feteira, Praia da Vitoria, Ribirinha, Angra do Heroismo, Lajes, Sao Mateus, and Sao Bartolomeu.
This epicenter is at 101-102 degrees from Hokkaido and from the Drake Passage
and my have been promoted by constructive interference of energy from those
two sources.
O: 17DEC2025 21:42:36 38.4N 26.8W ML=4.4 EMSC AZORES ISLANDS, PORTUGAL
EMSC reported an earthquake of M 4.2 in the Adriatic Sea was felt with intensity up to IV in the area(s) of the Adriatic Sea in Croatia at Babino Polje, Zaton Doli, Ston, Slano, Orasac, Janjina and lightly in Bosnia and Herzegovina, Montenegro, among others.
O: 17DEC2025 22:07:46 42.6N 17.6E ML=4.2 EMSC ADRIATIC SEA
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-18 00:00 UT 11.0S 91.4E 60 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 60 kts. It has reversed direction again and is now moving to the west and is expected to dissipate in the next day. The antipode is at 11N 89W - is in the area off the coast of Central America. Some enhanced seismicity in El Salvador and Nicaragua is likely to continue near 12N 88W as this cyclone tracks to the east over the next several days.
A tropical Cyclone (INVEST 93S) may be forming south of Bali. This system is currently located at 12S 112E and is moving WNW with winds up to 33 kts. Some seismic enhancement has accompanied this systen in Bali and Java over the past several days and is expected to continue. The antipode at 12N 68W is south of Puerto Rico but is not highly seismic but areas of northern Venezuela and Trinidad and Tobago may see enhanced seismicity as this storm continues to slowly rotate around its current position.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 17, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5050 0827 0840 0901 C1.3 (December 17, 2025) 2.3E-03
Southern California M 2.2 08:31 UT
Banda Sea M 4.4 08:51 UT
5060 0948 0955 1000 C1.0 (December 17, 2025) 7.5E-04
Hokkaido M 5.0 09:50 UT
Central California M 3.2 10:01 UT
5110 2320 2335 2341 C2.0 (December 17, 2025) 1.9E-03
El Salvador M 3.3 23:20 UT
Costa Rica M 3.5 23:23 UT
Northern California M 2.1 23:37 UT
Banda Sea M 4.0 23:27 UT
South of Panama M 5.6 23:08 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 18 and disturbed December 19-20. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 18 17 10 22:00 4 68 119
A moderate geomagnetic storm appears to be starting at high latitudes (kp 6) around 09:00 UT on December 18.
This could encourage seismicity in sub-solar sections and high latitudes. NOAA's GOES Magnetometer
shows a spike in geomagnetic field intensity near 07:10 UT which could indicate
the sudden commencemtne of this storm. Areas which could see immediate changes is
seismicity include Afghanistan and central Asia. Additional
enhancement could occur near regions at local solar midnight (western U.S and
Canada) within an hour or so of commencement.
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 17, 2025
Notable earthquakes and events:
Tropical Cyclone Bakung continued to move to the west near 12 degrees south
latitude today south of Sumatra. In previous issues this storm had been
expected to trigger antipodal seismicity in the region of Nicaragua - an
event which occurred with M 4.4-5.3 and was documented in this summary in
the previous issue. It also appears to have triggered an M 4.2 the day before
off the west coast of Central America - also discussed in previous issues
of this summary. It was then expected to continue to enhance seismicity
in El Salvador as it moved to the west as noted in the previous issue of this
summary:
"Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 55 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 12N 87W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 87W as this cyclone tracks to the east over the next several days." (December 15-16, 2025)
With this in mind, it can now be reported that an M 4.2-4.7 did occur early on UT
December 17, 2025 at the antipode of TC Bakung in El Salvador consistent
with this prior forecast. The M 4.2-4.7 was followed 13 minutes later by an M 3.5
aftershock. MARN is the local seismic network operated out of San Salvador (Servicio National de Estudios Territoriales (SNET El Salvador)
and is likely the best data network for local events in El Salvador. The
last earthquake with M>=4.7 within about 100 km of today's event in El Salvador
was recorded by NEIC as an M 4.9 on November 9, 2025 but the last of significantly larger magnitude
in this area was an M 5.4 on June 18, 2025. This event followed several
hours after an M 6.2 in Oaxaca, Mexico northwest of its epicenter.
In addition to being antipodal to TC Bakung this epicenter is also at the sixth node
(60 degrees) from Yukon, Canada and may have been promoted by energy from that
source.
O: 17DEC2025 07:17:47 12.7N 88.4W MB=4.7 GFZ OFFSHORE EL SALVADOR
O: 17DEC2025 07:17:47 12.5N 88.5W MB=4.2 NEIC OFFSHORE EL SALVADOR
O: 17DEC2025 07:31:19 12.6N 88.6W MB=3.5 MARN OFFSHORE EL SALVADOR
Two moderate earthquakes occurred today in the Southern Mid-Atlantic area.
These events of M 5.1 and M 5.0 were not reported felt in this remote region.
They occurred within minutes of local solar noon and were probably promoted
by two of the strongest solar flares of the day of C1.5 (#4990) and C1.9 (#5020)
which peaked or were peaking at the time of these earthquakes. Data
on these solar flares follow. Note that foreshocks in El Salvador
and an M 3.0 in the San Francisco Bay area of California also coincided with these flares.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4990 1336 1343 1347 C1.5 (December 16, 2025) 1.1E-03
Southern Mid-Atlantic M 5.0 13:45 UT M 5.1 13:44 UT
El Salvador M 2.6 13:45 UT
5020 1347 1351 1355 C1.9 (December 16, 2025) 1.0E-03
San Francisco Bay M 3.0 13:53 UT
O: 16DEC2025 13:35:46 13.1N 90.1W MB=2.8 EMSC OFFSHORE EL SALVADOR
O: 16DEC2025 13:44:55 12.5N 88.2W MB=2.6 EMSC OFFSHORE EL SALVADOR
O: 16DEC2025 13:44:15 43.7S 16.3W MB=5.1 EMSC SOUTHERN MID-ATLANTIC RIDGE
O: 16DEC2025 13:45:25 43.8S 16.2W MB=5.0 EMSC SOUTHERN MID-ATLANTIC RIDGE
The earthquakes of M 5.1 and M 5.0 in the southern Mid-Atlantic Ridge today
were not reported felt in this remote area. They had been expected in this
summary at this time in forecast 178071 to occur within about 25 km of
these epicenters around December 12, 2025. The last earthquake of M>=5.1
within about 200 km of these epicenter occurred as an M 5.2 on April 18, 2024 but the
last of significantly larger magnitude was an M 5.5 and M 5.7 on November 9, 2018.
A similar M 5.7 hit the area on June 7, 2013. At the time this summary noted:
"The earthquake in the Southern Mid-Atlantic Ridge
was the strongest within 200 km of that epicenter in nearly 20 years.
One two events of similar size have occurred in this region in the past 25
years - an M 5.8 on March 22, 1992 and an M 6.0 on September 29, 1993. This
is a remote area and today's event was not reported felt." (June 7, 2013)
This epicenter is at 143 degrees from Yukon, Canada and may have been promoted
by energy from that source.
O: 16DEC2025 13:44:15 43.7S 16.3W MB=5.1 EMSC SOUTHERN MID-ATLANTIC RIDGE
O: 16DEC2025 13:45:25 43.8S 16.2W MB=5.0 EMSC SOUTHERN MID-ATLANTIC RIDGE
The largest earthquake in the world today (on this relative quiet day in seismicity)
was an M 5.3 in the Solomon Islands. It was not reported felt in this remote
area. A tropical Cyclone passed over this epicenter several days ago and may
have helped promote today's earthquake as noted in previous issues of this
summary:
"A tropical cyclone may be froming in the Santa Cruz Islands north of Vanuatu. This system with winds up to 33 kts is tracking to the south and east and may help promote enhanced seismicity in northern Vanuatu and Santa Cruz Islands in the next two days." (December 13-16, 2025)
O: 16DEC2025 09:18:44 11.6S 163.3E MW=5.3 EMSC SOLOMON ISLANDS
An earthquake of M 3.0 in the area of San Francisco Bay, California also coincided
with the above-mentioned solar flares. This earthquake was reported by NEIC
to have been felt with intensity III in Oakland, San Ramon, Alamo, San Leandro, Berkeley, , Walnut Creek, Dublin and Castro Valley and II in Alameda, Haywrd, Pleasanton, Danville, San Francisco, San Rafael, Stockton, Sunnyvale, Hayward and Livermore.
It continues a series of events near this epicenter which has been ongoing
for several weeks and could be precursory to a moderate to large regional
earthquake with origin near this epicenter. A major earthquake on this
portion of the Calaveras Fault is still considered unlikely at this time though. The M 3.0 was followed by an
aftershock of M 2.9 near local solar midnight.
O: 16DEC2025 13:53:27 37.8N 121.9W MB=3.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 17DEC2025 06:11:34 37.8N 121.9W MD=2.9 EMSC SAN FRANCISCO BAY AREA, CALIF.
An earthquake of M 3.1 also shook the area of eastern Los Angeles today joining
other recent earthquakes in southern California. NEIC reported it was felt with intensity
III in Crestline, Fontana, Riverside, Corona, San Bernardino, Rialto, Rancho Cucamonga, Lytle Creek, Riverside, Loma Linda, Ontario, Rialto, and II in Morno Valley, Colton, Grand Terrace, San Bernardino, Upland, Mira Loma, Redlands, Chino Hills, Glendora, Orange, Lancaster, Corona, Highland, San Dimas, Bloomington, California.
O: 17DEC2025 04:04:06 34.1N 117.5W ML=3.0 EMSC GREATER LOS ANGELES AREA, CALI
The area of western Los Angeles, California also continued the current swarm
near Santa Barbara today. Today's events included an M 3.2-3.3. NEIC reported
it was felt with intensity III in California at Ojai, Oak View, Ventura and II in Carpinteria, with lesser shaking in Santa Barbara, Oak Park, Canyon Country, Simi Valley, Newbury Park and Calabasas.
O: 16DEC2025 15:06:06 34.4N 119.3W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 16DEC2025 15:06:06 34.4N 119.3W ML=3.3 NEIC SOUTHERN CALIFORNIA
O: 16DEC2025 15:18:11 34.4N 119.3W ML=2.1 EMSC SOUTHERN CALIFORNIA
O: 16DEC2025 19:19:09 34.4N 119.3W ML=2.0 EMSC SOUTHERN CALIFORNIA
O: 16DEC2025 21:14:06 34.5N 119.0W ML=1.9 EMSC SOUTHERN CALIFORNIA
An unusual earthquake of M 3.4 south of the Channel Islands, California was
the strongest event in North America excluding Alaska today. NEIC reported
it may have been felt with intensity II in California at Sherman Oaks and Baldwin Park.
This appears to be part of the seismic enhancement of the California region
at this time and occurred at an unusual epicenter off the coast of Southern
California. The last earthquake within about 100 km of this epicenter
with M>=3.4 was recroded by NEIC as an M 4.1 on January 3, 2012 about 70 km
northeast of today's epicenter and is the only such event in this region
in at least 35 years. It may be precursory to a stronger regional earthquake
during this period of elevated seismicity in California.
This epicenter is at 104 degrees from recent strong earthquakes in the
Central Philipines and from the Drake Passage and at 144 degrees from
TC Bakung and may have been promoted by constructive interference from
energy associated with those sources.
O: 16DEC2025 21:38:33 32.9N 119.9W ML=3.5 EMSC OFF COAST OF CALIFORNIA
The largest earthquake in North America today was an M 5.0 in southern Alaska near
Chiniak. It may have been felt lightly in Sterling, Alaska but is well off
the coast of Alaska and is unlikely to have been widely felt.
This is an unusual epicenter and appears to be an outer rise event suggesting
a stronger earthquake down the subduction zone may be in preparation in southern
Alaska (with a possible tsunami). The last earthquake within about
200 km of this epicenter with M>=5 occurred on March 2, 2020. A major earthquake
hit near this epicenter with M 7.9 on January 23, 2018. At the time this summary
noted:
"The great earthquake in Alaska of M 7.9-8.0 early on January 23 may extend the
strong seismic triggering at distance from nodal and triggering distances from that epicenter.
The relation of the M 6.0-6.4 in Java and the subsequent Alaskan earthquake of M 8.0
at 103-104 degrees from Java probably begins a series of strong earthquake related
to Alaska. One promoter of the earthquake in Alaska may have been stresses from the
strong nor'easter of early to mid-January. Strong earthquakes off the northwestern
portion of the North American place often occur within days of strong hurricanes
and nor'easters as previously noted on many occasions in this summary. The map of
possible triggering areas from Alaska shows the 103 degree zone passing near northern Chile, the Central Atlantic, Java and Sumatra and New Zealand among the most active seismic region. The 144 zone
passes near the South Sandwich Islands and southern Indian Ocean. Some of the triggering
stresses may combine to trigger strong earthquake in areas where they were expected
following the M 7.6 north of Honduras of January 10. Tidal triggering is also
a likely promoter for additional global seismicity. In general maximum magnitudes
are likely to shift up to 0.5 units upward from those previously expected with the
chance of strong related seismicity increasing up to 50% at nodal distances and at short distances
from the Alaskan and Honduras epicenter." (January 23, 2018)
Today's earthquake occurred near local solar noon and may have been promoted by tidal and/or geomagnetic stresses
which tend to maximize near this hour.
This epicenter is at the eighth node (45 degrees) from Hokkaido, Japan
and may have been promoted by energy from that source.
O: 16DEC2025 23:35:26 56.4N 148.6W MW=5.0 EMSC GULF OF ALASKA
NEIC reported an earthquake of M 4.5 in Metropolitana, Chile was felt with intensity up to II-III in the area(s) of Metropolitana, Chile at Lampa and Santiago.
EMSC reported moderate shaking in Chile at Providencia, Nunoa, La Pintana, Quillota.
O: 16DEC2025 07:42:41 33.0S 70.2W MB=4.5 EMSC VALPARAISO, CHILE
EMSC reported an earthquake of M 4.1 in Turkey-Syria border Turkey-Syria border Turkey-Syria border Turkey-Syria border Turkey-Syria border in Deizciler, Payas, Iskenderun, Belen, Kuzeytepe, Hidirbey, Reyhanli, Bahce and in Syria at Afrin, Sharan, I'zaz, Salqin among others.
O: 17DEC2025 01:15:09 36.7N 36.4E ML=4.1 EMSC TURKEY-SYRIA BORDER REGION
EMSC reported an earthquake of M 4.1 in Western Turkey was felt with intensity up to IV in the area(s) of Western Turkey at Aksu, Muratpasa, Kepez, Belek, Konyaalti, Kumluca, Burdur, Alanya.
O: 16DEC2025 13:11:01 37.0N 30.9E MB=4.1 EMSC WESTERN TURKEY
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-17 00:00 UT 12.2S 92.8E 70 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 70 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 12N 88W - is in the area of El Salvador. Some enhanced seismicity in El Salvador and Nicaragua is likely to continue near 12N 88W as this cyclone tracks to the east over the next several days.
A tropical Cyclone (INVEST 93S) may be forming south of Bali. This system is currently located at 12S 113E and is moving SSW with winds up to 33 kts. Some seismic enhancement has accompanied this systen in Bali and Java over the past several days and is expected to continue. The antipode at 12N 67W is south of Puerto Rico but is not highly seismic but areas of northern Venezuela and Trinidad and Tobago may see enhanced seismicity as this storm continues to slowly rotate near its current position.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 16, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4960 + 0358 0417 0500 G18 5 XRA 1-8A C3.0 3.1E-03 *
Southern California M 2.0 04:01 UT
Kamchatka M 4.3 02:45 UT
Chiapas M 4.0 04:31 UT
Nicaragua M 5.3 04:55 UT
4990 1336 1343 1347 C1.5 (December 16, 2025) 1.1E-03
Southern Mid-Atlantic M 5.0 13:45 UT M 5.1 13:44 UT
El Salvador M 2.6 13:45 UT
5020 1347 1351 1355 C1.9 (December 16, 2025) 1.0E-03
San Francisco Bay M 3.0 13:53 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 16 active December 17 minor storms December 18 and disturbed December 19. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 12 12 6 11:00 4 81 117
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
An M 3.7 in Oaxaca, Mexico coincided with the GRB at 09:03 UT as did an M 3.5 in Michoacn, Mexico at 09:04 UT and an M 2.6 in Yukon, Canada at 09:03 UT
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
December 16, 2025
Notable earthquakes and events:
In the previous daily issue of this summary it was noted:
"... lack of these external triggers for seismicity allows the effects of other triggering mechanisms (such as ocean storms) to be more
easily seen in seismicity data. Two ocean storms are currently active -
Tropical Cyclone Bakung south of Sumatra, Indonesia with winds up to 85
kts and Tropical Cyclone 08E in northern Sumatra with winds up to 50 kts.
In the previous issue effects from TC Bakung were expected as:
"Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 85 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 11N 89W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 89W as this cyclone tracks to the west over the next several days." (December 13-24, 2025)
With this in mind a pair of earthquakes at 12N 89W off the west coast of
Central America today (as forecast in this summary - see above quote), takes
on some significance. While only a moderate event of M 4.2 with an aftershock
of M 3.6, this epicenter off central America is not highly seismic. The last
earthquake within about 150 km of today's epicenter with M>=4.2 occurred
nearly three months ago on September 23, 2025 with M 5.0. Today's event
off central America is at the exact antipode of the eye of TC Bakung at the
time of its occurrence and was likely promoted by focused antipodal energy.
TC Bakung has now reversed direction. The new direction takes it near the
antipode with El Salvador and Nicaragua and perhaps Guatemala but also
reduces the strength of the storm. A moderate earthquake induced by antipodal
focused energy in this area remains a likelihood in the next three days." (December 14-15, 2025)
and
"Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 65 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 11N 89W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 88W as this cyclone tracks to the east over the next several days." (December 15, 2025)
The current position of TC Bakung is at:
TC BAKUNG 2025-12-16 00:00 UT 11.6S 93.1E 55 kts South of Sumatra
The antipode of this position is at 12N 87W in Nicaragua.
With this in mind, it is useful to review some of today's seismicity in the
area of El Salvador and Nicaragua in terms of this and seismic wave
triggering. The strongest earthquake of the day was an M 5.7 in the region
of Guam and the Mariana Island. It was followed 20 minutes later by an
M 3.1 in El Salvador at 13N 89W as the PP-wave arrived at this epicenter
118 degrees from Guam. A stronger earthquake of M 5.3 occurred at 107 degrees
from Guam in the Ionian Sea, Greece as the SS-wave arrived from Guam.
In regard to the previous discussion the M 3.1 in El Salvador may be of
some interest. Of more interest was an M 4.4-5.3 in Nicaragua which occurred
near local solar midnight. That event occurred near the coast of Nicaragua
at 12N 87W within about 50 km of the antipode of the eye of TC Bakung as expected in this summary in the previous issue (see above)
and appears have been promoted by the expected antipodal effects from TC Bakung.
This earthquake in Nicaragua of M 4.4 is the strongest within about 150
km of this epicenter since a similar M 5.3 on November 17, 2025 - a month ago.
The last earthquake of stronger magnitude in this area was an M 6.2 on October 12, 2024.
At the time this summary noted:
"The strongest earthquake in the world today was an M 6.2 in Costa Rica. NEIC reported maximum intensity IV was felt in Guanacaste, Costa Rica at Belen and Santa Cruz and II-III in Liberia, La Cruz, Nicoya, in Alajuela, Costa Rica at Naranjo, San Juan, it was also felt with intensity II-III in Nicaragua at San Marcos, San Juan del sur Rivas and Altagracia Rivas.
EMSC reported strong shaking and a rumble in Costa Rica at Tamarindo, Veintisiete, Arenal and in Nicaragua at San Marcos, Managua.
This earthquake in Costa Rica is the strongest within about 200 km of this
epicenter since an M 6.5 on November 13, 2017 and an 6.7 on April 21, 2022. At the time this summary noted
"The last earthquake in Nicaragua within about 250 km of today's epicenter with
equal or larger magnitude occurred on September 5, 2012 with M 7.6 and prior
to that an M 7.0 on October 9, 2004." (April 21, 2022, Octover 12, 2024)
EMSC reported the Nicaragua earthquake was felt lightly in Tola, Managua and Nararote, Nicaragua.
NEIC reported intensity III was felt in Nicaragua at Diriamb, Carazo and Catarina Masaya and II in Managua, Nicaragua.
This event in Nicaragua may also have been promoted by the strongest solar
flare of the day - a C3.1 which was in progress when the earthquake occurred
and peaked minutes earlier. Data read from the GOES X-Ray Flux chart (online)
from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
XXXX 0400 0420 0500 C3.1 (December 16, 2025) 3.1E-03 *
O: 16DEC2025 04:55:50 11.6N 86.5W ML=4.4 EMSC NEAR COAST OF NICARAGUA
O: 16DEC2025 04:55:52 11.6N 86.5W ML=4.6 INET NEAR COAST OF NICARAGUA
O: 16DEC2025 04:55:52 11.6N 86.5W ML=4.7 GFZ NEAR COAST OF NICARAGUA
O: 16DEC2025 04:55:52 11.6N 86.5W MW=5.3 MARN NEAR COAST OF NICARAGUA
The strongest earthquake in the world today was an M 5.7 in the region north
of Guam, Mariana Islands. NEIC reported intensity IV in Rota, Hagatna, Yigo, Saipan, Santa Rita, Mangilao and III in Tinian, Tamuning, Barrigada, Guam and in the northern Mariana Islands at Garapan, Saipan.
EMSC reported moderate shaking in Saipan and in Guam at Yigo Village,Dededo Village, Tamuning-Tumon-Harmon, and Hagatna with material thrown from shelves.
This epicenter is at the sixth node (60 degrees) from TC Bakung and the fith node (72 degrees)
from Yukon, Canada and may have been promoted by energy from those sources.
O: 15DEC2025 23:06:13 14.3N 145.8E MW=5.7 EMSC ROTA REGION, N. MARIANA ISLAND
NEIC reported earthquakes of M 2.3 and M 2.8 continued to be felt with intensity up to II-III in the area(s) of west of Los Angeles, California at Santa Paula and Fillmore.
This epicenter is at 143 degrees from TC Bakung and at 104 from the central Philippines
and may have been promoted by energy from those sources.
O: 15DEC2025 15:26:36 34.5N 119.0W ML=2.3 EMSC SOUTHERN CALIFORNIA
O: 16DEC2025 01:29:46 34.5N 119.0W ML=2.8 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 5.3 in the Ionian Sea was felt with intensity up to II-III in the area(s) of the Ionian Sea at Messini, Greece.
EMSC reported moderate shaking in Greece at Katastarion, Laganas, Ambelokipoi Alonia, Kalliteros, Zakynthos, Myrtia, Lechaina, Pyrgos, Kato Achaia, Vrachnaiika, Patra, Kalamata.
O: 15DEC2025 23:41:47 37.5N 20.2E MW=5.3 EMSC IONIAN SEA
NEIC reported an earthquake of M 4.8 in Pakistan was felt with intensity up to II-III in the area(s) of Pakistan with III in Karachi Sind.
EMSC reported moderate shaking in Pakistan at Karachi, Malir Cantonment,
P-phases from an M 5.6 in Kamchatka 17 minutes earlier (at 73 degrees distance)
may have triggered this earthquake in Pakistan as they were coincident at
the time of its occurrence.
This epicenter is at the eighth node (45 degrees) from TC Bakung; the fourth node from
Yukon Canada; the fifth node from Kamchatka and the sixth node from Mindanao
and may have been promoted by energy from those sources.
O: 15DEC2025 19:50:59 25.5N 66.6E MB=4.8 EMSC PAKISTAN
The strongest earthquake in the U.S. or Canada today was an M 4.9 in the central
Andreanof Islands, Aleutians, Alaska. NEIC reported it was felt with intensity
up to III in Adak, Alaska.
This epicenter is located at 144 degrees from the Drake Passage and may
have been promoted by energy from those sources. It is also at the 12th node
(30 degrees) from Hokkairo, Japan.
O: 15DEC2025 18:03:53 51.5N 176.4W MW=4.9 EMSC ANDREANOF ISLANDS, ALEUTIAN IS
NEIC reported an earthquake of M 5.6 in Kamchatka may have been felt with intensity up to II-III in the area(s) of Kamchatka.
EMSC reported light to moderate shaking in Petropavlovsk-Kamchatsky, Vilyuchinsk, Yelizovo, Russia.
This continues the aftershocks from major earthquakes in the area which began
about 5 months ago in mid-July, 2025.
This epicenter is at the seventh node (51-52 degrees) from recent strong
earthquakes in central Philippines and may hav been promoted by energy from
those sources.
O: 15DEC2025 19:33:06 51.8N 161.1E MW=5.6 EMSC OFF EAST COAST OF KAMCHATKA
O: 15DEC2025 08:11:16 52.0N 160.2E Mw=5.3 EMSC OFF EAST COAST OF KAMCHATKA
O: 16DEC2025 02:11:29 52.0N 160.6E mb=4.3 EMSC OFF EAST COAST OF KAMCHATKA
O: 16DEC2025 04:25:08 52.0N 161.1E mb=4.3 EMSC OFF EAST COAST OF KAMCHATKA
The earthquake was followed 15.5 minutes later by an M 5.0 in the Southwest Indian
Ridge at a distance of 117 degrees. This earthquake was not felt in this remote
region. The P-diffracted phase from Kamchatka was at this epicenter in the
Southwest Indian Ocean at the time this subsequent earthquake occurred. It
is possible this seismic phase from Kamchatka triggered the earthquake in
the Southwest Indian Ridge.
This epicenter is located at 144 degrees from Yukon, Canada; 101 degrees from
Hokkaido, Japan and the fifth node from the central Philippines and may
have been promoted by energy from those sources.
O: 15DEC2025 19:48:30 28.3S 62.9E MB=5.0 EMSC SOUTHWEST INDIAN RIDGE
NEIC reported an earthquake of M 2.9 in Washington State was felt with intensity up to II-III in the area(s) of Washington State with II in Seattle, Bellingham and Mount Vernon.
O: 15DEC2025 16:29:38 48.5N 121.8W ML=3.0 EMSC WASHINGTON
O: 15DEC2025 15:06:20 48.5N 121.8W ML=2.7 EMSC WASHINGTON
NEIC reported an earthquake of M 4.0 in North Island, New Zealand was felt with intensity up to II-III in the area(s) of North Island, New Zealand in Palmerston North Manawatu-Wanganui.
GeoNet reported the following for this earthquake:
O: 15DEC2025 12:05:08 40.4S 175.9E ML=4.5 GEONET Felt with moderate to light intensity in the area southeast of Wellington, New Zealand and in southern North Island and northern South Island. 1542 reports of felt events were made of which 639 reported weak and 761 light intensity with 135 reports of moderate shaking and 6 with strong and 0 severe and 1 with extreme intensity came from the area.
This epicenter is at the antipode of an event in Portugal of December 13, 2025.
At the time this summary noted in this regard:
"The antipode of this epicenter (in Portugal) is near Wellington, New Zealand - an active seismic area." (December 13, 2025)
This earthquake occurred within minutes of local solar midnight and may have
been promoted by energy from tides or geomagnetic sources.
O: 15DEC2025 12:05:08 40.4S 175.9E MW=4.0 EMSC NORTH ISLAND OF NEW ZEALAND
EMSC reported an earthquake of M 4.0 in the Caucasus, Russia was felt with intensity up to IV in the area(s) of the Caucasus, Russia in Zelenokumsk.
EMSC reported an earthquake of M 4.0 in Turkey was felt with intensity up to IV in the area(s) of Turkey in Gunyazi, Antakya, Dursunlu, Hancagiz, Anayazi, Altinozu, Serinyol, Belen, Ceyhan, Mersin, Mahmutlar and in Nicosia, Geroskipou, Cyprus and in Syria at Aleppo.
This epicenter is at the fifth node (72 dgrees) from TC Bakung and may have
been promoted by energy from that source.
O: 15DEC2025 09:20:00 36.2N 36.1E ML=4.0 EMSC TURKEY-SYRIA BORDER REGION
EMSC reported an earthquake of M 4.0 in Portugal was felt with intensity up to IV in the area(s) of Portugal in Evora, Arraiolos, Estremoz, Redondo, Vila Vicosa, Pinhal Novo, Barreiro, Laranjeira, Alges, Alcanede.
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-16 00:00 UT 11.6S 93.1E 55 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 55 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 12N 87W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 87W as this cyclone tracks to the east over the next several days.
TROPICAL CYCLONE 08P
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 08P 2025-12-16 00:00 UT 15.1S 172.1E 45 kts Fiji
Tropical Cyclone 07P continued today in the region of Fiji with winds up to 45 kts. It could help promote moderate seismicity in Vanuatu and/or Fiji as it tracks south and east in this active seismic area. The antipode is at 15N 8W - is not a seismic active area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 15, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0400 0420 0500 C3.1 (December 16, 2025) 3.1E-03 *
Southern California M 2.0 04:01 UT
Kamchatka M 4.3 02:45 UT
Chiapas M 4.0 04:31 UT
Nicaragua M 5.3 04:55 UT
4830 0120 0129 0134 C1.9 (December 15, 2025) 1.1E-03
4840 0140 0148 0156 C1.8 (December 15, 2025) 1.6E-03
4850 0302 0316 0324 C1.4 (December 15, 2025) 1.8E-03
Central America M 4.2 03:29 UT
El Salvador M 3.2 03:43 UT
Costa Rica M 3.7 03:53 UT
4880 1152 1205 1215 C1.3 (December 15, 2025) 1.5E-03
North Is. New Zealand M 4.0 12:05 UT
4890 1221 1225 1234 C2.0 (December 15, 2025) 1.4E-03
4910 1720 1728 1749 C3.9 (December 15, 2025) 5.0E-03
4950 2323 2336 2343 C1.3 (December 15, 2025) 1.3E-03
Ionian Sea M 5.3 23:42 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 16 active December 17 minor storms December 18. Solar M-flare chance: 20% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 6 9 5 15:00 5 73 118
A strong Gamma Ray Burst was recorded by SWIFT on December 14, 2025 at 09:02:17 UT (#251214B). A preliminary UVOT Magnitude of V=17.09 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 15, 2025
Notable earthquakes and events:
Geomagnetic effects on seismicity were at low levels today. The earth
experienced a couple of low C-class solar flares and little in the way of
geomagnetic storms. This could lead to moderate gradual increases in seismicity
at high latitudes in the next day or two. This lack of these external
triggers for seismicity allows the effects of other triggering mechanisms (such as ocean storms) to be more
easily seen in seismicity data. Two ocean storms are currently active -
Tropical Cyclone Bakung south of Sumatra, Indonesia with winds up to 85
kts and Tropical Cyclone 08E in northern Sumatra with winds up to 50 kts.
In the previous issue effects from TC Bakung were expected as:
"Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 85 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 11N 89W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 89W as this cyclone tracks to the west over the next several days." (December 13-24, 2025)
With this in mind a pair of earthquakes at 12N 89W off the west coast of
Central America today (as forecast in this summary - see above quote), takes
on some significance. While only a moderate event of M 4.2 with an aftershock
of M 3.6, this epicenter off central America is not highly seismic. The last
earthquake within about 150 km of today's epicenter with M>=4.2 occurred
nearly three months ago on September 23, 2025 with M 5.0. Today's event
off central America is at the exact antipode of the eye of TC Bakung at the
time of its occurrence and was likely promoted by focused antipodal energy.
TC Bakung has now reversed direction. The new direction takes it near the
antipode with El Salvador and Nicaragua and perhaps Guatemala but also
reduces the strength of the storm. A moderate earthquake induced by antipodal
focused energy in this area remains a likelihood in the next three days.
The M 4.2 today is located at the sixth node (60 degrees) from Yukon, Canada
and may have been promoted by energy from that source.
O: 15DEC2025 03:29:27 11.9N 89.4W ML=4.2 EMSC OFF COAST OF CENTRAL AMERCICA
Several moderate earthquake of M 4.2 also occurred today in northern Vanuatu as
TC 08P was passing through the area. It was not reported felt.
O: 14DEC2025 20:46:32 11.9S 167.9E MB=4.2 EMSC SANTA CRUZ ISLANDS
NEIC reported an earthquake of M 4.1 hit the region of northern California today
and was followed by a series of light aftershocks. NEIC reported it was felt widely with intensity IV in California
at Glen Ellen, Kenwood, Santa Rosa an Penngrove; III in Tracy, Cotati, Sonoma, Petaluma, Bolinas, Sacramento, Oakdale, Daly City, San Jose, Greenbrae, San Francisco, Saint Helena, and II in Napa, Sebastopol, El Sobrante, Stanford, Napa, and as far as 100 km from the epicenter.
Aftershocks were felt with intensity III in Santa Rosa, Rohnert Park, Saint Helena, and II in Sonoma, San Francisco, Salinas, Napa, Cotati and Penngrove, California.
The mainshock of M 4.1 is the strongest earthquake near this epicenter since an M 4.4 and M 4.3 on
September 14, 2022 and prior to that an M 4.4 on August 3, 2006. An M 6.0 hit about 50 km southeast
the current epicenters on August 24, 2014 in the Napa area of California.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an unusually large M 4.4 in the Geysers
region of Northern California. It was followed by an M 3.9 aftershock a minute later.
NEIC reported it was felt with intensity V in Santa Roas, Fulton, IV in Windsor, Rohnert Park, Sebastopol, Calistoga, Healdsburg, Monte Rio, Occidental, Jenner with lesser shaking within 500 km in northern California.
The last earthquake in northern California within the Geysers area of equal or
larger magnitude occurred on December 14, 2016 with M 5.0. " (September 14, 2022)
and
"Strong earthquakes hit first in northern San Francisco Bay and Napa, California (M 6.0-6.4)
and about half a day later in Southern Peru (M 6.6-7.0). NEIC received nearly
40,000 felt reports on the San Francisco Bay quake, a record to date. The
California quake was felt throughout most of northern and central California
and as far as Idaho, Oregon, Washington and Nevada up to 800 km from the epicenter with intensity II.
It did extensive damage, up to $1 billion, in the epicentral area but while
there were two reported heart attacks and several severe injuries no on was
killed in this earthquake in California. The earthquake in Peru was at an intermediate depth and a remote area, and
while widely felt, there were no immediate reports of damage or casualties
from this event. Tidal stresses from the new moon today as well as geomagnetic,
and solar events and a GRB may have helped trigger this earthquake. A series of hurricanes,
including Lowell and Marie may also have helped set both areas up for today's
strong earthquakes. A detailed suggested timeline of triggering for this earthquake
can be found below.
The mainshock north of San Francisco was followed by a series of light aftershocks
including those of M 3.5, 2.4, 2.3, 2.3, 2.3, 2.3, 2.5, 3.6, 2.4, 2.8, 2.2 and 2.3.
The events of M 3.5-3.6 were felt with lesser intensity, but throughout much
the same area as the mainshock. NEIC gives intensity IV in Napa and IV in San Francisco, Mountain View, Alameda, Fairfield, Fremont, Orinda, Vallejo, Oakland, Berkeley, Richmond, Inverness, Novalo, Santa Rosa, Middletown, Windsor, California
for these events. A complete listing from NEIC of felt reports per community
can be found in the "CALIFORNIA" section of this summary. This is the strongest
earthquake in the San Francisco area since the Loma Prieta quake of October, 1989.
Damage to shops and wineries was considerable and ranged from fallen building
facades in Napa to broken wine bottles in wineries to fallen and smashed objects
throughout the region. One reader (PC) wrote to say she did not hear any rattling
but movement was obvious 30 km from the epicenter. While no one was killed
in the quake at least three were seriously hurt and more than 100 injured.
The contents of many homes were thrown to the floor and destroyed. The city
manager of Napa says the damage is too great for local resources and is asking
for outside help. At least six major fires were triggered and several mobile
homes were destroyed in Napa. Water systems and electricity were out throughout
the region. At least 15 building in Napa will have to be destroyed due to extensive
damage. Cell phone systems were overwhelmed, as often happens during and after
and earthquake anywhere, by people calling and sending photos of damage. The economic loss to the region is expected to initially be around
$1 billion US dollars. Much of this will be recovered in the rebuilding and
recovery after the quake, so, except for immediate losses, the impact on the
overall long-term economy of the area will probably be minimal.
Foreshocks of M 3.2 hit this epicenter on August 5 and M 2.8 on July 20 and were widely felt in the
region. This is the first earthquake of M>=6 to hit within the borders of California
since the San Simeon quake nearly 10 years ago on December 22, 2003 of M 6.4-6.6
and an M 6.0 near Parkfield on September 28, 2004. The other events of M>6 have
all occurred off the northern coast in June, 2005 (M 7.2, 6.6); January 10, 2010
(M 6.5) and March 10, 2014 (M 6.9)." (August 24, 2014)
O: 14DEC2025 23:30:42 38.4N 122.6W MW=4.1 EMSC NORTHERN CALIFORNIA
O: 14DEC2025 23:38:39 38.4N 122.6W ML=3.1 EMSC NORTHERN CALIFORNIA
O: 14DEC2025 23:43:11 38.4N 122.6W MD=2.1 EMSC NORTHERN CALIFORNIA
O: 15DEC2025 00:04:20 38.4N 122.6W ML=3.3 EMSC NORTHERN CALIFORNIA
O: 15DEC2025 00:07:09 38.4N 122.6W MD=2.4 EMSC NORTHERN CALIFORNIA
O: 15DEC2025 02:01:32 38.4N 122.6W MD=2.4 EMSC NORTHERN CALIFORNIA
O: 15DEC2025 02:03:17 38.4N 122.6W MD=2.5 EMSC NORTHERN CALIFORNIA
The swarm in the San Francisco Bay area of California also continued today. This
series near San Ramon was reported by NEIC to have been felt with intensity
up to IV in Danville and III in San Ramon, Dublin, and II in Pleasanton and Alameda
among others. This is possibly precursory activity leading up to a stronger
quake near this epicenter which would most likely be activated by a major
solar flare near local solar midnight or local solar noon. The combination of moderate
quakes in central and northern California over the past week suggests such
an event will occur sooner rather than later.
The activity in central California today is located at the fifth node (72 degrees) from
Hokkaido and at 102-103 degrees from recent major earthquakes in central
Philippines and may have been promoted by energy from those sources.
O: 14DEC2025 21:01:22 37.5N 121.8W MD=2.0 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 15DEC2025 06:46:53 37.8N 121.9W MD=2.8 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 15DEC2025 06:52:14 37.8N 121.9W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
The strongest earthquake of the day was an M 5.2 in the South Sandwich Islands. Like
previous earthquakes in the area this earthquake occurred within minutes of local
solar midnight and may may have been promoted by tidal and/or geomagnetic
stresses which maximize near this hour. It was not reported felt in this remote
area.
An earthquake of M 4.8 also occurred in the Drake Passage west of the South
Sandwich Islands. It was not reported felt. This event occurred within
minutes of local solar noon and may have been promoted by tidal and/or
geomagnetic stresses.
The epicenter in the Drake Passage is at 106 degrees from TC Bakung and
may have been promoted by energy from that source.
O: 15DEC2025 00:43:16 58.8S 25.7W MB=5.2 EMSC SOUTH SANDWICH ISLANDS REGION
O: 14DEC2025 15:54:19 59.3S 60.0W MB=4.8 EMSC DRAKE PASSAGE
NEIC reported an earthquake of M 3.2 in Central Alaska was felt with intensity up to II-III in the area(s) of Central Alaska in Fairbanks
This epicenter is at the eighth node (45 degrees) from Hokkaido, Japan and may have been promoted by energy from that source.
O: 14DEC2025 23:08:14 64.9N 148.8W ML=3.2 EMSC CENTRAL ALASKA
NEIC reported an earthquake of M 5.1 off the west coast of Honshu, Japan was felt with intensity up to II-III in the area(s) of off the west coast of Honshu, Japan in Ishikawa with V in Nanao and III in Kanazawa.
The mainshock occurred within minutes of local solar midnight and may
have been promoted by tidal and/or geomagnetic stresses.
O: 14DEC2025 14:26:51 37.0N 136.6E MB=5.1 EMSC NEAR WEST COAST OF HONSHU,
O: 14DEC2025 19:03:36 37.0N 136.6E mb=4.9 EMSC NEAR WEST COAST OF HONSHU,
EMSC reported an earthquake of M 2.0 in Utah was felt with intensity up to IV in the area(s) of Utah at Saratoga Springs.
This epicenter is at 143 degrees from Tropical Cyclone Bakung and may have been
promted by energy from that source.
O: 14DEC2025 13:32:29 40.4N 111.9W ML=2.0 EMSC WASATCH FRONT URBAN AREA, UTAH
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-15 00:00 UT 10.9S 91.6E 65 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 65 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 11N 89W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 88W as this cyclone tracks to the east over the next several days.
TROPICAL CYCLONE 08P
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 08P 2025-12-15 00:00 UT 14.6S 170.5E 50 kts Vanuatu
Tropical Cyclone 07P formed today in the region of Vanuatu with winds up to 50 kts. It could help promote moderate seismicity in Vanuatu as it tracks south and east in this active seismic area. The antipode is at 15N 10W - is not a seismic active area.
A tropical cyclone may be froming in the Santa Cruz Islands north of Vanuatu. This system with winds up to 33 kts is tracking to the south and east and may help promote enhanced seismicity in northern Vanuatu and Santa Cruz Islands in the next two days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 14, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4730 0012 0038 0056 C1.2 (December 14, 2025) 2.6E-03
Kuril Is. M 4.6 00:21 UT
Crimea M 4.1 00:38 UT
Halmahera M 4.3 00:55 UT
Southern Sumatra M 5.1 00:58 UT
4740 0724 0742 0804 C3.8 (December 14, 2025) 7.1E-03
4750 0905 0911 0915 C1.2 (December 14, 2025) 7.8E-04
4760 1223 1235 1254 C1.9 (December 14, 2025) 3.1E-03
4770 1655 1713 1717 C2.3 (December 14, 2025) 2.1E-03
4780 1804 1812 1816 C1.0 (December 14, 2025) 7.5E-04
Hokkaido M 4.7 18:09 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 15-. Solar M-flare chance: 25% X-class: 1% proton storm: 1%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 7 6 4 15:00 3 78 119
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 14, 2025
Notable earthquakes and events:
The strongest earthquakes of the day in the world occurred as events of M 5.4-5.5
in the Rat Islands, Alaska and in northern Chile in the Tarapaca area of
Iquique with IV and in Calama, Antofagasta with intensity III. EMSC reported moderate shaking at Iquique and Arica, Chile. The event in northern Chile
occurred at a latitude which was at sub-solar conditions today, the 14th of December.
When an M 3.9 occurred near this latitude in Brazil yesterday, enhanced seismicity at this latitude
was expected at this time as:
"EMSC reported an earthquake of M 3.9 in Brazil was felt with intensity up to IV in the area(s) of Brazil at Araxa and included a very loud noise.
This epicenter occurred near 20 South latitude and was near sub-solar on this
date. It is expected that sub-solar latitudes will see enhanced seismicity
and at this time this includes area of northern Chile in the Tarapaca and
Antofagasta areas (21-23S); the Loyalty Islands; and others." (December 13, 2025)
The last earthquake in the Tarapaca area of Chile within about 200 km of today's
epicenter with M>=5.4 was an M 5.5 on September 19, 2024 but the last of significantly
larger nagnitude was an M 6.1 on January 2, 2025. At the time this summary noted:
"A moderately strong M 5.5-5.9 earthquake also occurred today in the region of
northern Chile in the Tarapaca area. NEIC reported it was felt with intensity V in Iquique and III in Arica.
EMSC reported strong and long shaking in Chile at Pozo Almonte, Iquique, Arica, and in Peru at Tacna and Pocollay.
The last earthquake within about 200 km of this epicenter in the region of
Tarapaca, Chile with M>=5.5 occurred as an M 5.7 on May 26, 2025. The only other
event of M>=5.5 in the area in the past year was an M 6.1 on January 2, 2025." (September 19, 2025)
This epicenter is at 144 degrees from Hokkaido, Japan and from Tropical Cyclone Bakung
and may have been promted by energy from those sources.
O: 13DEC2025 12:18:46 21.2S 69.1W MW=5.4 EMSC TARAPACA, CHILE
The M 5.5 in the Rat Islands, Alaska was the strongest event in North America
today. It was not reported felt in this remote area. The last earthquake
with M>=5.5 in the Rat Islands within about 200 km of today's epicenter
occurred as an M 5.9 on August 28, 2025. The last of M>=6 in this area was
an M 6.3 on December 14, 2022 (exactly three years ago today). At the time this summary noted:
"The strongest earthquake in the U.S. or Canada or the world today was an M 6.3
in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote
region. A smaller earthquake of M 5.3 hit the Rat Islands on December 10, 2022.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.3 in the Rat Islands, Aleutians, Alaska. It was not reported felt in this remote epicentral area.
The last earthquake with M>=5.3 in the Rat Islands was an M 6.3 half a year
ago on June 4, 2022. At the time this summary noted in this regard:
"The event of M 6.3 in the Rat Islands was not reported felt in this remote area.
This is the strongest earthquake in the Rat Islands since an M 6.4 on April 2, 2019.
These appear to be aftershocks of the M 7.9 that hit about 50 km southeast of today's epicenter
on June 23, 2014. Today's event occurred near local solar noon and was likely
promoted by high tidal stresses which maximize near this hour. It may also have
been promoted by the recent geomagnetic storm." (June 5, 2022)
Today's event also occurred near local solar noon and may have been promoted
by high tidal stresses with the full moon of December 8." (December 11, 2022, December 14, 2022)
Today's earthquake in the Rat Islands occurred near local solar
midnight and may have been promoted by tidal and/or geomagnetic
stresses which maximize near this hour.
This epicenter is located at 146 degrees from the Drake Passage and at the sixth
node (60 degrees) from major quakes in the Central Philippines and may have
been promoted by energy from those sources.
O: 13DEC2025 10:51:00 52.0N 178.4E MW=5.5 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
An M 4.6 was also located today in the Loyalty Islands at 22 South
latitude (as noted above - the latitude of sub-solar conditions on this date).
It was not reported felt in this remote area.
This epicenter is at the fourth node (90 degrees) from Yukon, Canada and at the seventh node
from Mindanao and may have been promoted by energy from those sources.
O: 13DEC2025 11:13:05 22.6S 171.1E MB=4.6 EMSC SOUTHEAST OF LOYALTY ISLANDS
Unfelt earthquakes also occurred at opposite ends of the Atlantic Ocean region today.
An M 4.6 occurred near the northern end of the Atlantic in the Reykjanes
and an M 5.0 occurred in the South Sandwich Islands. These two earthquakes
both occurred within minutes of local solar noon and were probably promoted
by tidal and/or geomagnetic stresses. The event in the Reykjanes Ridge occurred 26 minutes
after the quake in the South Sandwich Islands at a distance of 117 degrees. Various S-phases from
the South Sandwich Islands would have been at the Reykjanes Ridge when
that event occurred and may have been helpful in triggering this later earthquake.
O: 13DEC2025 14:04:33 58.9S 25.8W MB=5.0 EMSC SOUTH SANDWICH ISLANDS REGION
This epicenter in the South Sandwich Islands is at 147 degrees from the
Yukon, Canada and may have been promoted by energy from that source.
O: 13DEC2025 14:30:42 57.8N 32.5W MB=4.6 EMSC REYKJANES RIDGE
An M 4.6 in the West Chile Rise also occurred today but was not felt in this remote area.
This epicenter is at 147 degrees from Hokkaido, Japan and may have been
promoted by energy from that source.
O: 14DEC2025 05:51:47 43.1S 82.4W MB=4.6 EMSC WEST CHILE RISE
The swarm of earthquakes west of Los Angeles, California continued today.
This contained the largest event in the swarm thus far - an M 3.6. NEIC reported it was felt with
intensity IV in California at Oxnard; III in Snta Barbara, Porter Ranch, Santa Paula,Sunland, Frazier Park, Fillmore, Panorama City, Granada Hills, Newhall, Stevenson Ranch, Canoga Park, Ventura and II inNorthridge, Agoura Hills, Oak View, Chatsworth, Carpinteria, Van Nuys, Sherman Oaks, Calabasas, Castaic, Canyon Country, Newbury Park, Camarillo, Santa Monica, Ojai, Los Angeles, Simi Valley, West Hills and within about 50 km of the epicenter.
In previous issues this summary noted this swarm as:
"A swarm of earthquakes ranging between M 1.0 and M 3.3 occurred today in the
region west of Los Angeles near Santa Barbara. NEIC reported these were felt
with intensity up to III in California at Santa Paula and II in Los Angeles, Santa Clarita, Thousand Oaks, Fillmore, Ventura, Moorpark. This swarm included at least
20 shocks with six of M>=2.5 and was not dissimilar to other recent swarms in California in
the past week. The press did not report any major damage with this swarm.
These epicenters area at 104 degrees from major earthquakes in the Central
Philippines and may have been promoted by energy from those sources." (December 12, 2025)
Today's activity began near local solar noon and may have been promoted
by tidal and/or geomagnetic stresses which maximize near this hour.
O: 13DEC2025 21:38:27 34.3N 119.3W ML=2.7 EMSC GREATER LOS ANGELES AREA, CALI
O: 14DEC2025 01:03:34 34.5N 119.0W ML=3.5 EMSC SOUTHERN CALIFORNIA
O: 14DEC2025 01:03:34 34.5N 119.0W ML=3.6 NEIC SOUTHERN CALIFORNIA
O: 14DEC2025 01:15:49 34.5N 119.0W ML=2.4 EMSC SOUTHERN CALIFORNIA
O: 14DEC2025 01:53:09 34.5N 119.0W ML=2.2 EMSC SOUTHERN CALIFORNIA
O: 13DEC2025 21:47:06 34.4N 119.3W ML=2.0 EMSC GREATER LOS ANGELES AREA, CALIF.
O: 13DEC2025 23:24:06 34.4N 119.3W ML=2.1 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 2.9 in San Francisco, California was felt with intensity up to II-III in the area(s) of San Francisco, California with III in San Ramon and II in Danville, Oakley, San Francisco, Dublin and Pleasanton.
Today's activity began near local solar noon and may have been promoted
by tidal and/or geomagnetic stresses which maximize near this hour.
O: 13DEC2025 21:44:08 37.8N 121.9W MD=2.9 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 13DEC2025 22:09:07 37.8N 121.9W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 14DEC2025 02:57:33 37.8N 121.9W MD=2.3 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 2.7 north of San Francisco near Kenwood, California was felt with intensity up to II-III in the area(s) of north of San Francisco near Kenwood, California with III in Santa Rosa, Kenwood and II in Sloughhouse, Oakley, Rohnert Park, Glen Ellen.
O: 13DEC2025 17:30:35 38.4N 122.6W MD=2.5 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.0 in Central Alaska was felt with intensity up to II-III in the area(s) of Central Alaska at Willow and Talkeetna.
O: 13DEC2025 13:08:33 62.1N 149.3W ML=3.0 EMSC CENTRAL ALASKA
P: 19DEC2025 178020 62.7N 150.6W 3.2-5.1 CAAAA Central Alaska
EMSC reported an earthquake of M 4.1 in Crimea, Ukraine was felt with intensity up to IV in the area(s) of Crimea, Ukraine in Sevastopol.
This epicenter is located near the fifth node (72 degrees) from Tropical Cyclone Bakung; Yukon, Canada;
Kamchatka and Hokkaido and may have been promoted by coherent energy from
those sources.
O: 14DEC2025 00:38:06 44.4N 33.2E MB=4.1 EMSC CRIMEA REGION, UKRAINE
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-14 00:00 UT 10.4S 91.2E 85 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 85 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 11N 89W - is in the area of Nicaragua and El Salvador. Some enhanced seismicity in Nicaragua, El Salvador and Costa Rica is possible near 12N 89W as this cyclone tracks to the west over the next several days.
A tropical cyclone may be froming in the Santa Cruz Islands north of Vanuatu. This system with winds up to 33 kts is tracking to the south and east and may help promote enhanced seismicity in northern Vanuatu and Santa Cruz Islands in the next two days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 13, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4580 0204 0211 0217 C1.1 (December 13, 2025) 8.7E-04
Veracruz M 4.0 02:03 UT
Nicaragua M 3.1 02:07 UT
Mindanao M 4.5 02:02 UT
Oaxaca M 4.1 02:13 UT
4590 0251 0259 0314 C1.2 (December 13, 2025) 1.6E-03
Central Mediteranean M 2.5 02:53 UT
Kermadec M 3.6 02:53 UT
Kamsas M 2.7 02:49 UT
Eastern Turkey M 1.5 02:52 UT
4610 0356 0359 0402 C1.6 (December 13, 2025) 5.9E-04
4620 0411 0421 0427 C1.6 (December 13, 2025) 1.3E-03
Fiji M 4.5 04:31 UT
San Francisco M 2.2 04:31 UT
4640 0741 0748 0753 C1.5 (December 13, 2025) 9.9E-04
Java M 2.7 07:41 UT
4660 1036 1051 1102 C8.6 (December 13, 2025) 8.1E-03
Rat Is. M 5.5 10:51 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 14 disturbed December 15-16. Solar M-flare chance: 30% X-class: 1% proton storm: 5%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 14 18 8 16:00 4 76 122
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 13, 2025
Notable earthquakes and events:
Planetary k-index reached moderate geomagnetic storm levels UT December 12 of 5.0 towards
the end of the UT day. This was accompanied by K-index of 6 at high latitudes with
the strongest geomagnetic storm in 9 days (high latitude A 52).
GOES magnetometers show this was most likely a sudden commencement storm starting around 21:00-22:00 UT.
This is likely to dampen seismicity for at least two days while induced telluric currents
reform.
It was a relatively quiet day in global seismicity. Only three events of M>5
were recorded in the past 24 hours. These occurred in the Izu Islands, Japan with M 5.3
and as an M 5.2 in the northern Kuril Islands. Neither of these were felt.
The third was an M 5.2 in the South Sandwich Islands in the South Atlantic
Ocean area. This event occurred within minutes of local solar noon and may
have been promoted by strong tidal and/or geomagnetic effects which tend
to maximize near this hour.
O: 12DEC2025 13:55:54 59.6S 26.0W MB=5.2 EMSC SOUTH SANDWICH ISLANDS REGION
O: 12DEC2025 17:43:14 50.9N 156.9E MW=5.2 EMSC KURIL ISLANDS
O: 12DEC2025 19:03:12 32.4N 137.5E MW=5.3 EMSC IZU ISLANDS, JAPAN REGION
This epicenter is at the sixth node (60 degrees) from the Yukon, Canada and
may have been promoted by energy from that source.
An M 4.9 was also widely felt in the region of Tokyo, Japan today. As this occurred
while JMA continued their mega-earthquake alert, it caused concern in Tokyo, but no damage was reported.
NEIC reported it was felt with intensity IV in Saitama, Chiba, Niigata, Tokyo, Tochigi Prefectures of Japan with III in Ibaraki, Tokyo and Saitama.
EMSC reported strong shaking in Japan at Ryugasaki, Misato, Kamagaya, Narita, Toda, Urayasu, Tokyo, Musashino, Kolubunji, Kawasaki, Fukushima and Isesaki.
This epicenter is at the sixth node (60 degrees) from the eye of Tropical Cyclone Bakung and
may have been promoted by energy from that source.
O: 12DEC2025 10:05:20 36.2N 140.1E MB=4.9 EMSC NEAR EAST COAST OF HONSHU, JAP
NEIC reported an earthquake of M 2.7 in northern Kansas was felt with intensity up to II-III in the area(s) of northern Kansas with IV in Enterprise, III in Lost Springs, Saint Joseph and II in Hope.
O: 13DEC2025 02:49:01 38.7N 97.1W ML=2.7 EMSC KANSAS
NEIC reported an earthquake of M 3.8 in Wyoming was felt with intensity up to II-III in the area(s) of Wyoming with III in Lander and Riverton.
O: 13DEC2025 00:38:36 42.5N 108.4W ML=3.8 EMSC WYOMING
NEIC reported an earthquake of M 3.5 in Central California was felt with intensity up to II-III in the area(s) of Central California with IV in Templeton; III in Cayucos, Cambria, Bradley, Paso Robles, Atascadero an San Simeon and II in Morro Bay, Los Osos and San Miguel.
O: 12DEC2025 23:30:31 35.6N 120.8W MW=3.5 EMSC CENTRAL CALIFORNIA
The strongest earthquake in the U.S. or Canada today was an M 4.8 in the
Fox Islands, Alaska. NEIC reported it may have been felt in the epicentral area near Nikolski, Alaska.
O: 12DEC2025 18:14:58 52.1N 169.4W MB=4.8 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
NEIC reported an earthquake of M 4.2 in Cyprus was felt with intensity up to II-III in the area(s) of Cyprus at Kedares and Pegeia.
EMSC reported in Cyprus with moderate to strong intensity at Paphos, Geroskipou, Cloakas, Emba, Konia, Lempa, Mesa Chorio, Mesogi, Kissonerga, among others.
The mainshock was preceded about 1.5 minutes earlier by an M 3.5 foreshock. That event
was reported felt lightly in Cyprus at Paphos, Geroskipou, Chlorakas, Timi among others.
An earlier foreshock of M 2.7 was felt in Cyprus at Tala, Kissonerga, Pegeia, Emba, Paphos, Koloni, Geroskipou, Limassol and Voroklini with light intensity.
This epicenter is at the fifth node (72 degrees from Tropical Cyclone Bakung
and at the ninth node from Mindanao and the third node from the Drake
Passage and may have been promoted by energy from those sources.
O: 12DEC2025 17:20:18 34.7N 32.4E MW=4.2 EMSC CYPRUS REGION
O: 12DEC2025 17:18:41 34.7N 32.3E MW=3.5 EMSC CYPRUS REGION
O: 12DEC2025 13:03:59 34.9N 32.5E MW=2.7 EMSC CYPRUS REGION
An earthquake in the southern Indian Ridge near Broken Ridge today of M 4.9
was not reported felt in this remote area. It is antipodal to western
Texas where swarming of minor earthquakes is common. This event may lead
to a swarm in Texas in the next two days.
This epicenter is at 142 degrees from the Yukon, Canada; the fourth node (90 degrees)
from Hokkaido and the sixth node (60 degrees from Central Philippines and
may have been promoted by energy fron those sources.
O: 12DEC2025 15:34:28 31.5S 79.1E MB=4.9 EMSC BROKEN RIDGE
EMSC reported an earthquake of M 4.1 in Portugal was widely felt with intensity up to IV in the area(s) of Portugal at Fornos de Algodres with a loud rumbling sound and heavy swelling shaking, it was also felt with moderate shaking in Celorica de Beira, Mesquitela, Guarda, Aguiar da Beira, Trancoso, Mangualde, Manteigas, Sequeira, Famalicao, Manteigas, Seia, Nelas, Rio de Loba among others within about 150 km of the epicenter.
This is the strongest earthquake in Portugal within about 150 km of this epicenter
since an M 4.8 on September 4, 2018 and an M 4.5 on January 23, 2003.
At the time of the 2018 event this summary noted:
"An earthquake of M 4.8 hit off the western coast of Portugal today.
NEIC reported this earthquake of M 4.8 NW of Portugal was felt with intensity IV in Portugal at Canedo, Vila Nova de Gaia, Porto and Baguim do Monte, Norte, Portugal. in the area(s) of
The antipode of this epicenter is located in the Cook Strait between North and
South Island, New Zealand. Some sympathetic seismicity in North or South Island
New Zealand may follow this event in Portugal in the next several days.
Great earthquakes such as the Lisbon quake of November 1, 1755 (M 8.0) and
several in the late 1960's can occur west of Portugal in this tectonic regime
and can be accompanied by tsunamis. This is the strongest earthquake within
about 200 km of this epicenter in at least 30 years. An M 4.8 last hit
about 300 km southwest of this on July 26, 2007." (September 4, 2018)
and in 2003 as:
"An M 5.1 occurred this morning (UT) in the region near Portugal. This was the
strongest event within 200 km of this epicenter since a swarm on May 21 and
22, 1997 more than five years ago. That swarm had included events of M 5.3 and
5.6" (January 23, 2003)
Today's earthquake occurred within a few minutes of local solar midnight and may have
been promoted by tidal and/or geomagnetic stresses which maximize near this hour.
The antipode of this epicenter is near Wellington, New Zealand - an active seismic area.
This epicenter is at 105 degrees from Teopical Storm Bakung; and the fifth
node (72 degrees) from the Yukon Canada and may have been promoted by energy from those sources.
O: 13DEC2025 00:38:09 40.6N 7.5W ML=4.1 EMSC PORTUGAL
EMSC reported an earthquake of M 3.9 in Brazil was felt with intensity up to IV in the area(s) of Brazil at Araxa and included a very loud noise.
This epicenter occurred near 20 South latitude and was near sub-solar on this
date. It is expected that sub-solar latitudes will see enhanced seismicity
and at this time this includes area of northern Chile in the Tarapaca and
Antofagasta areas (21-23S); the Loyalty Islands; and others.
The last earthquake of M>=3.9 within about 200 km of this epicenter in Brazil occurred
as an M 4.3 on June 18, 2024. The only other such earthquake in the past 35 years in the area was
an M 4.1 on May 22, 1998. This epicenter is at 107 degrees from the Yukon, Canada
and may have been promoted by energy from that source.
O: 13DEC2025 01:10:41 19.5S 47.0W MR=3.9 EMSC MINAS GERAIS, BRAZIL
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE BAKUNG (07S)
---- ------- ---------- -------- ----- ------ ------- ---------------
TC BAKUNG 2025-12-13 00:00 UT 8.6S 95.3E 55 kts South of Sumatra
Tropical Cyclone Bakung (07S) continued today in the region south of Sumatra winds up to 55 kts. It could help promote moderate seismicity in Sumatra as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 9N 85W - is in the area of Costa Rica and Nicaragua. Some enhanced seismicity in Panama,, Nicaragua and Costa Rica is possible near 9N 85W as this cyclone tracks to the west over the next several days.
A tropical cyclone may be froming in the Santa Cruz Islands north of Vanuatu. This system with winds up to 33 kts is tracking to the south and east and may help promote enhanced seismicity in northern Vanuatu and Santa Cruz Islands in the next two days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 12, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4410 0450 0505 0514 M2.0 (December 12, 2025) 1.7E-02
Guerrero M 4.0 04:50 UT
Honshu M 4.7 04:58 UT
4420 0527 0544 0553 M1.1 (December 12, 2025) 1.6E-02
4460 0910 0919 0929 C2.6 (December 12, 2025) 2.8E-03
Fiji M 4.4 09:14 UT
4480 1343 1348 1352 C2.2 (December 12, 2025) 1.3E-03
South Sandwich Is. M 5.2 13:55 UT
Nicaragua M 4.0 13:33 UT
4500 1437 1447 1451 C2.8 (December 12, 2025) 1.7E-03
Ceram Sea M 4.6 14:49 UT
4520 1543 1558 1612 C3.5 (December 12, 2025) 4.4E-03
4530 1722 1757 1829 C3.2 (December 12, 2025) 1.1E-02
Cyprus M 4.2 17:21 UT
Oaxaca M 4.2 17:20 UT
Kuril Is. M 5.2 17:43 UT
Baja California M 3.4 17:43 UT
Java M 2.8 17:50 UT
Fox Is. M 4.8 18:14 UT
4550 2211 2218 2224 C1.3 (December 12, 2025) 1.1E-03
Nicaragua M 3.9 22:17 UT
4560 2331 2341 2347 C1.2 (December 12, 2025) 1.1E-03
Central California M 3.5 23:31 UT
Jalisco M 4.1 23:37 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active December 13-14 disturbed December 15. Solar M-flare chance: 30% X-class: 1% proton storm: 5%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 28 52 19 19:00 6 124 135
Planetary k-index reached moderate geomagnetic storm levels today of 5.0 towards
the end of the UT day. This was accompanied by K-index of 6 at high latitudes with
the strongest geomagnetic storm in 9 days (high latitude A 52). This is likely
to dampen seismicity for at least two days while induced telluric currents
reform.
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 12, 2025
Notable earthquakes and events:
A swarm of earthquakes ranging between M 1.0 and M 3.3 occurred today in the
region west of Los Angeles near Santa Barbara. NEIC reported these were felt
with intensity up to III in California at Santa Paula and II in Los Angeles, Santa Clarita, Thousand Oaks, Fillmore, Ventura, Moorpark. This swarm included at least
20 shocks with six of M>=2.5 and was not dissimilar to other recent swarms in California in
the past week. The press did not report any major damage with this swarm.
These epicenters area at 104 degrees from major earthquakes in the Central
Philippines and may have been promoted by energy from those sources.
O: 11DEC2025 17:33:48 34.5N 119.0W ML=2.3 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 17:50:21 34.5N 119.0W ML=2.0 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 18:21:02 34.5N 119.0W ML=2.5 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 18:27:32 34.5N 119.0W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 18:27:32 34.5N 119.0W ML=3.3 NEIC SOUTHERN CALIFORNIA
O: 11DEC2025 18:29:05 34.5N 119.0W ML=2.5 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 18:31:11 34.5N 119.0W ML=2.7 EMSC SOUTHERN CALIFORNIA
O: 11DEC2025 18:59:55 34.5N 119.0W ML=2.2 EMSC SOUTHERN CALIFORNIA
A strong aftershock of the M 7.6 in Hokkaido occurred today (UT December 12) with M 6.7.
NEIC reported intensity IV shaking in Aomori, Japan at Hachinohe and Misawa and in Sapporo, Hokkaido with II-III in Tokyo, Miyagi, Kanagawa Prefectures.
EMSC reported moderate shaking in Japan at Takizawa, Shiraoi, Sapporo, Niseko Town, Urayasu, Tokyo, Yokohama and in Yuzhno-Kurilsk, Russia.
An M 5.5 aftershock occurred about 37 minutes later and was likely felt with intensity up to IV in the epicentral area.
An M 5.1 foreshock was felt with intensity III in Iwanai, Hokkaido, Japan.
The M 6.7 quake is the second strong aftershock after a similar one hours after the mainshock.
This earthquake occurred within minutes of local solar noon and was likely
promoted by strong geomagnetic and/or tidal stresses which tend to maximize
near this hour. When the prolonged global seismic quiet ended on November 27, 2025
this summary had noted that a strong earthquake appeared likely around December
12 as:
"Some have wondered if the recent long quiet period in global seismicity will
be followed by a major global earthquake soon. Historical data suggests
about 30% chance of an earthquake in the world of M>=7.4 in the next month
on the basis of the 25 most prolonged global quiet periods of the past 35 years
as previously published in this summary. The most likely dates of such events
are 15-17 days after November 27, 2025 - when the quiet ended - and 21-22 days
after. This translates to a higher than likely probability of such a major
event in the next month within a day of December 13, 2025 and December 19, 2025" (November 30, 2025)
O: 11DEC2025 22:09:19 41.0N 142.8E MB=5.1 EMSC HOKKAIDO, JAPAN REGION
O: 12DEC2025 02:44:13 41.0N 142.8E Mw=6.7 EMSC NEAR EAST COAST OF HONSHU,
O: 12DEC2025 03:21:40 41.0N 142.9E mb=5.5 EMSC HOKKAIDO, JAPAN REGION
O: 12DEC2025 07:05:30 41.0N 143.1E ML=4.0 EMSC HOKKAIDO, JAPAN REGION
O: 12DEC2025 07:55:30 41.2N 142.5E ML=4.7 EMSC HOKKAIDO, JAPAN REGION
O: 11DEC2025 17:04:20 41.4N 142.9E mb=4.4 EMSC HOKKAIDO, JAPAN REGION
O: 11DEC2025 18:11:06 41.4N 142.6E mb=4.8 EMSC HOKKAIDO, JAPAN REGION
O: 12DEC2025 04:58:19 40.8N 143.0E mb=4.7 EMSC NEAR EAST COAST OF HONSHU,
A moderate geomagnetic storm occurred off and on today with peak K-index of 5.7. This
may have promoted the M 6.6 in Hokkaido and the swarm west of Los Angeles, California.
The GOES magnetometer showed spikes in the field intensity occurring atou 02:30 UT
on December 12 (followed several minutes later by the M 6.6 in Hokkaido);
at 18:40 UT on December 11 and at 15:00 UT on December 11 (followed by an M 4.7 in Taiwan
and an M 2.7 in Louisiana several minutes later). These may have been promoted by the sudden change
in geomagnetic field intensity. The M 2.7 in Louisiana was reported by NEIC
to have been felt with intensity III in Coushatta, Louisiana and lightly in
Natchez, Mississippi.
O: 11DEC2025 16:07:50 32.0N 93.3W ML=2.7 EMSC LOUISIANA
An earthquake of M 3.9 in the area of Java, Indonesia occurred today.
EMSC reported it was lightly felt in Indonesia at Cangkeuteuk Sabrang.
This event may have been promoted by antipodal focused energy from an M 5.5
in Colombia which occurred yesterday and was noted in this summary at the
time as:
"Antipodal activity is common with earthquakes in this region of Colombia. The
most likely antipodal events would be at 6S 106E in the Sumba Strait area of Indonesia.
This area is active at this time and an M 4.1 occurred at this antipodal epicenter
earlier in the day" (December 11, 2025)
These epicenters are at the sixth node (60 degrees) from the M 7.6 in Hokkaido,
Japan and may have been promoted by energy from that source.
O: 11DEC2025 16:50:30 7.0S 105.4E ML=3.2 EMSC JAVA, INDONESIA
O: 11DEC2025 16:11:53 7.1S 105.4E ML=3.9 EMSC JAVA, INDONESIA
O: 11DEC2025 17:09:03 7.1S 105.6E ML=2.6 EMSC JAVA, INDONESIA
O: 12DEC2025 04:40:02 7.1S 106.0E ML=2.7 EMSC JAVA, INDONESIA
O: 11DEC2025 12:25:22 7.5S 106.0E ML=3.1 EMSC JAVA, INDONESIA
O: 12DEC2025 05:38:25 7.9S 107.0E ML=2.8 EMSC JAVA, INDONESIA
NEIC reported an earthquake of M 4.9 north of Tokyo, Japan was felt with intensity up to II-III in the area(s) of Honshu, Japan with IV in Saitama, Chiba, Niigata, Tokyo and Tochigi Prefectures and III in Ibaraki, Tokyo, Saitama, Kanagawa, Chiba.
NEIC reported an earthquake of M 3.3 in Central California was felt with intensity up to II-III in the area(s) of Central California with III in Hollister, Salinas and II in Los Gatos, Fresno, Salinas, Campbell.
These epicenters are at the fifth node (72 degrees) from Hokkaido, Japan
and 103 degrees from central Philippines and may be related to energy from
those sources.
O: 12DEC2025 01:19:43 36.8N 121.5W ML=3.3 NEIC CENTRAL CALIFORNIA
O: 12DEC2025 01:19:43 36.8N 121.5W ML=3.2 EMSC CENTRAL CALIFORNIA
O: 12DEC2025 01:57:14 36.8N 121.5W MD=2.5 EMSC CENTRAL CALIFORNIA
O: 12DEC2025 03:33:35 36.8N 121.5W MD=2.3 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.4 in Southern Peru was felt with intensity up to II-III in the area(s) of Southern Peru in Ica.
This epicenter is near 141 degrees from Hokkaido, the eighth node (45 degrees) from the
Drake Passage and near the fourth node (90 degrees) from Yukon Canada and may
have been promoted by energy from those sources.
O: 12DEC2025 00:46:18 16.3S 73.9W MB=4.4 EMSC NEAR COAST OF SOUTHERN PERU
NEIC reported an earthquake of M 3.6 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii with III in Pahoa, Naalehu, Hakalau and II in Volcano, Captain Cook, Kihei and Hilo.
This epicenter is near the sixth node (60 degrees) from Hokkaido and may have
been promoted by energy from that source.
O: 11DEC2025 14:28:24 19.1N 155.4W ML=3.5 EMSC ISLAND OF HAWAII, HAWAII
NEIC reported an earthquake of M 3.2 in Northern California was felt with intensity up to II-III in the area(s) of Northern California with III in Bayside, Kneeland, Loleta, Trinidad, Arcata, McKinleyville and Samoa and II in Eureka, and Hoopa,
O: 11DEC2025 13:35:23 40.9N 124.0W ML=3.2 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.5 in Western Turkey was felt with intensity up to II-III in the area(s) of Western Turkey at Sile, Istanbul and Tire, Izmir.
EMSC reported an earthquake of M 4.1 in Romania was felt with intensity up to IV in the area(s) of Romania at Dancu.
SEISMIC EFFECTS OF TROPICAL CYCLONES
TROPICAL CYCLONE 07S
---- ------- ---------- -------- ----- ------ ------- ---------------
TC 07S 2025-12-12 00:00 UT 8.4S 97.3E 45 kts South of Sumatra
Tropical Cyclone 07S formed today in the region south of Sumatra winds up to 45 kts. It could help promote moderate seismicity as it tracks south of this active seismic area of eastern Indonesia. The antipode is at 9N 83W - is in the area of Costa Rica. Some enhanced seismicity in Panama and Costa Rica is possible near 9N 83W as this cyclone tracks to the west over the next several days.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 11, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4180 0248 0251 0255 C2.0 (December 11, 2025) 8.7E-04
4240 0609 0615 0618 C1.7 (December 11, 2025) 9.5E-04
Oaxaca M 4.0 06:06 UT
4260 0919 0929 0932 C2.4 (December 11, 2025) 1.4E-03
4270 0934 0938 0940 C5.0 (December 11, 2025) 1.5E-03
Chiapas M 4.1 09:40 UT
4280 1016 1022 1038 C2.4 (December 11, 2025) 2.8E-03
Yukon M 4.0 10:29 UT
Tonga M 4.9 10:38 UT
4290 1206 1212 1214 C2.3 (December 11, 2025) 9.6E-04
Java M 3.1 12:25 UT
4310 1516 1521 1525 C4.5 (December 11, 2025) 2.9E-03
Taiwan M 4.7 15:19 UT
4310 1525 1529 1531 C5.0 (December 11, 2025) 2.3E-03
4320 1539 1546 1551 C9.7 (December 11, 2025) 5.0E-03
4340 1708 1711 1714 C2.4 (December 11, 2025) 8.1E-04
Java M 2.6 17:09 UT
El Salvador M 4.9 17:18 UT
Sichuan, China M 4.7 17:18 UT
4350 2135 2146 2153 C1.8 (December 11, 2025) 2.0E-03
4370 2226 2232 2235 C2.3 (December 11, 2025) 1.0E-03
4390 2335 2345 2353 C2.4 (December 11, 2025) 2.1E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 12 active December 13-14. Solar M-flare chance: 65% X-class: 10% proton storm: 10%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 26 23 27 02:00 5 123 146
A moderate geomagnetic storm occurred off and on today with peak K-index of 5.7. This
may have promoted the M 6.6 in Hokkaido and the swarm west of Los Angeles, California.
The GOES magnetometer showed spikes in the field intensity occurring atou 02:30 UT
on December 12 (followed several minutes later by the M 6.6 in Hokkaido);
at 18:40 UT on December 11 and at 15:00 UT on December 11 (followed by an M 4.7 in Taiwan
several minutes later. These may have been promoted by the sudden change
in geomagnetic field intensity.
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 11, 2025
Notable earthquakes and events:
New tolls have been reported following the M 7.6 in Hokkaido, Japan of December 8 (UT).
Light damage in Pacific Coastal communities was reported as were tsunami waves
up to about a meter. Videos on the web showed a number of damaged structures.
AP reported at least 33 people were injured with one in serious condition. Most
of the injuries were caused by falling debris. The strongest tsunami was 70 km
in Iwate Prefecture but a number of other communities registered waves up
to 50 cm according to JMA. Some damage from the tsunami was reported by NHK
especially to oyster and fishing communities. At least 800 homes lost electricity
because of the quake. Bullet Trains and local lines were suspended temporarily
for inspection of damage. Some airline passengers were stranded for the night
in Hokkaido and some damage to airport terminals was reported. While some
water was spilt in nuclear facilities it was within tolerance levels and
no major damage was reported. JMA reported a slight risk of a major earthquake
from Hokkaido to Tokyo exists in the next several days. The earthquake
occurred during a regional snowstorm.
A moderate geomagnetic storm occurred today starting around 20:00-22:00 UT.
This reached a planetary K-index of 6.3 between 21:00 and 24:00 UT on
December 10. The only geomagnetic storm to reach planetary K since the storm
on November 12-13, 2025 was on December 3 when k-value reached 6.6 briefly
around 1800-2100 UT. Sudden commencement storms of this type can help
promote emhanced seismicity at high latitudes at the storm's onset. A moderately strong solar flare of M4.4 occurred late on UT day December 10, 2025.
This is the strongest solar flare since an X1.1 occurred on December 8 as
discussed earlier issues of this summary. Today's flare and geomagnetic storm apparently triggered
a moderate M 5.0 earthquake in northern Alaska which occurred within minutes
of local solar noon towards the end of this flare. Data from SWPC for this
flare and earthquake follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4100 2158 2208 2220 M4.4 (December 10, 2025) 1.9E-02 *
Northern Alaska M 5.0 22:17 UT
Baja California M 3.4 22:14 UT
The M 5.0 in northern Alaska today was the strongest event in the U.S. or
Canada (including Yukon) today. It earthquake in northern Alaska at 156 West longitude occurred within
minutes of local solar noon with a strong solar flare and was probably
promoted by tidal and/or geomagnetic stresses which are strongest under
these conditions. This is the strongest earthquake in Northern Alaska within
about 300 km of this epicenter since an M 5.0 on March 13, 2025 but the last
of significantly larger magnitude was an M 5.3 on October 14, 2018. This is the largest
earthquake in Alaska north of 68 North latitude in this region in at least
35 years. At the time of the event in March, 2025, this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.1 in north-central Alaska near Ambler.
It was not reported felt in this remote area but was probably felt with intensity up to VI in the epicentral area.
This earthquake occurred within minutes of local solar noon and was probably
promoted by tidal stresses with today's full moon and lunar eclipse which maximize
near this hour and were noted in previous issues of this summary ...
This event in northern Alaska could have been promoted by SFE associated with
flare 9740 which began five minutes before the quake and for which SFE were
maximized at this event of local solar noon in northern Alaska. Data from
SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9740 2159 2221 2224 C2.5 (March 13, 2025) 3.6E-03
Northern Alaska M 5.0 22:04 UT " (March 13, 2025)
Today's epicenter in northern Alaska is located at 144 degrees from the
major events in the Drake Passage and may have been promoted by energy
from those sources.
O: 10DEC2025 22:17:11 68.3N 156.5W MB=5.0 EMSC NORTHERN ALASKA
A moderate earthquake of M 5.5 also occurred today in Northern Colombia.
NEIC reported it was felt with intensity IV in Santander, Colombia at Piedecuesta, Bello, Antioquia, in Cundinamarca at Funza, Cota, Itagui and Tunja, Boyaca with III shaking in Mosquera, Sabaneta, Duitama, Medellin.
EMSC reported this earthquake in Colombia was felt with moderate to strong intensity
in Colombia at San Gil, Giron, Bucaramanga, Simacota, Charala, Paipa, Cucuta, Tunja, La Belleza, Gachancipa, Tocancipa, Cajica, Chia, Barrio San Luis, Cota, Funza, Bogota, Mosquera, Soacha, Medellin, Envigado, Itagui, Sabaneta, Caldas, Ricaurte, Ibague, Calarca, Armenia, Cartago.
This earthquake occurred near local solar midnight and may have been promoted
by tidal and/or geomagnetic effects which maximize near this hour.
The last earthquake of M>=5.5 within about 200 km of today's epicenter
was recorded by NEIC as occurring on March 10, 2015 with M 6.2. At the time
this summary noted:
"A strong earthquake of M 6.2 hit at an intermediate depth near Bucaramanga, Colombia today.
It was widely felt in the area of northern Colombia. EMSC reported moderate intensity
in Bucaramanga, Colombia, San Gil, Bogota, Copacabana, Soacha, Bello, El Retiro, Medellin, Sabaneta, La Estrella, Manizales, Cali, Colombia.
NEIC reported intensity V in San Jose de Miranda, Soacha, Pasca, Madrid, Chia, Leiva, and La Ceja, Colombia. Intensity IV was felt in Venezuela at San Cristobal, and II-III in Caracas, Chacao, Ejido, Trujillo, Maracaibo, Venezuela. It was also felt with intensity IV in Envigado, Guarne, Medellin, Barranquilla, Bogota, Chinchina, Manizales, Neira, Cota, La Calera, Puerto Salgar, Tabio, Villavicencio, Funza, LLa Calera, Puerto Salgar, Tabio, Floridablanca, Jordan, Florian, Piedcuesta and II-III in Calif, Sabana de Torres, Puerto Parra, Barrancabermeja, Salento, Armenia, Tiba, Puerto Santander, El Zulia, Fuente de Oror, Santa Maria, Aracataca, Sibato, San Bernardo, Medina, La Mesa, Cajica, Agua de Dios, Yopal, San Luis de Gaceno, Cartagena, Puerto Colombia, Sabaneta, Rionegro, La Union, Barbosa, Colombia.
Some structural damage was reported from Bogota including at City Hall. Air traffic
was briefly disrupted at Manizales where volcanic ash was in the atmosphere.
While residents fled into the streets during the quake, there were no injuries reported.
As often occurs cell phone networks were temporarily down after the quake. Over
use of these networks after an earthquake often occurs as people call others
to check on their status. The volcano Vallerica in Southern Chile continued
an eruption which began on March 4 and has caused extensive evacuation of more than 3000 residents of that
region. This may also have been related to recent solar activity including an
M8.2 flare which occurred hours earlier and the tidal effects of the full moon which
can often affect volcanism.
The earthquake in Colombia was probably promoted by strong solar flares which
occurred today. ...
The last earthquake of M>=6.2 within 150 km of this epicenter occurred
more than 25 years ago. The last event of M>=6.2 in this area was an M 6.2
on June 2, 1988. The last of larger magnitude was an M 6.5 on August 30, 1973
and nearly 50 years ago on July 29, 1967." (March 11, 2015)
Like previous significant earthquakes in this area of Colombia, this event
appears to have been promoted by a solar flare as it occurred near the end of solar
flare 3900 (M1.9), the strongest flare of the past two days. Data for this
flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3900 0731 0737 0800 M1.9 (December 10, 2025) 8.2E-03 *
Northern Colombia M 5.5 08:27 UT
Northern Sumatra M 4.9 07:42 UT
Mindanao M 3.4 07:41 UT
This epicenter is at the third node (120 degrees) from Hokkaido and at the fifth
node (72 degrees) from Yukon, Canada and 105 degrees from Kamchatka and may have been
promoted by energy from those sources.
O: 10DEC2025 08:27:07 6.8N 73.0W MW=5.5 EMSC NORTHERN COLOMBIA
NEIC reported an earthquake of M 4.5 in Western Turkey was felt with intensity up to II-III in the area(s) of Western Turkey in Sile, Istanbul and Tire, Izmir.
EMSC reported moderate shaking in Turkey at Sindirgi, Yagcilar, Bigadic, Akhisar, Balikesir, Kepsut, Soma, Golmarmara, Dursunbey, Salihi, Mustafakemalpasa, Bergama, Manisa among others.
O: 11DEC2025 07:06:15 39.2N 28.3E MW=4.5 EMSC WESTERN TURKEY
NEIC reported an earthquake of M 3.6 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Arcata.
O: 11DEC2025 00:35:33 40.4N 124.9W MW=3.3 EMSC OFFSHORE NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.2 in Northern Alaska was felt with intensity up to II-III in the area(s) of Northern Alaska in Wainwright.
O: 10DEC2025 22:17:11 68.3N 156.5W MB=5.0 EMSC NORTHERN ALASKA
O: 10DEC2025 22:17:11 68.3N 156.5W MB=4.2 NEIC NORTHERN ALASKA
EMSC reported an earthquake of M 4.3 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar in Mandalay, Pyin Oo Lwin, Yangon and Kyaukse.
O: 10DEC2025 09:35:36 22.6N 95.9E MB=4.7 EMSC MYANMAR
SEISMIC EFFECTS OF TROPICAL CYCLONES
No tropical cyclones are currently active.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 10, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3900 0731 0737 0800 M1.9 (December 10, 2025) 8.2E-03 *
Northern Colombia M 5.5 08:27 UT
Northern Sumatra M 4.9 07:42 UT
Mindanao M 3.4 07:41 UT
3720 0120 0125 0130 C7.8 (December 10, 2025) 4.7E-03
3750 0231 0247 0254 C8.0 (December 10, 2025) 7.5E-03
3850 0305 0313 0317 C6.5 (December 10, 2025) 5.8E-03
3770 0317 0324 0330 C9.5 (December 10, 2025) 7.3E-03
3780 0417 0422 0427 M1.2 (December 10, 2025) 5.8E-03
3800 0457 0503 0507 C4.1 (December 10, 2025) 2.4E-03
3810 0533 0538 0543 C3.1 (December 10, 2025) 1.8E-03
3840 0615 0626 0634 C3.6 (December 10, 2025) 3.3E-03
Hokkaido M 4.5 06:24 UT
Papua M 4.0 06:24 UT
Atacama M 5.2 06:38 UT
3860 0700 0704 0707 C2.0 (December 10, 2025) 9.6E-04
3870 0723 0729 0731 C2.5 (December 10, 2025) 3.4E-03
3900 0731 0737 0742 M1.9 (December 10, 2025) 8.2E-03
Mindanao M 4.5 07:41 UT
Colombia M 5.5 08:27 UT
3910 0946 0955 1002 M1.0 (December 10, 2025) 7.2E-03
Yukon M 4.3 09:50 UT
3920 1022 1029 1043 C4.1 (December 10, 2025) 4.5E-03
Oaxaca M 3.7 10:24 UT
3980 1332 1343 1349 M1.6 (December 10, 2025) 9.5E-03
New Guyinea M 5.3 13:30 UT
4010 1456 1505 1514 C3.4 (December 10, 2025) 3.1E-03
Hokkaido M 5.7 14:52 UT
Kermadec M 5.1 14:53 UT
4070 1918 1928 1936 C3.7 (December 10, 2025) 3.8E-03
Luzon M 4.1 19:22 UT
Sumba M 4.0 19:17 UT
4080 1958 2004 2007 C2.7 (December 10, 2025) 1.6E-03
Eastern China M 4.5 20:06 UT
4090 2019 2024 2034 C2.7 (December 10, 2025) 2.4E-03
4100 2158 2208 2220 M4.4 (December 10, 2025) 1.9E-02 *
Northern Alaska M 5.0 22:17 UT
Baja California M 3.4 22:14 UT
4150 2258 2305 2307 C4.8 (December 10, 2025) 2.0E-03
Kashmir M 3.7 23:02 UT
El Salvador M 4.2 23:02 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: disturbed December 11-12 active December 13. Solar M-flare chance: 75% X-class: 15% proton storm: 15%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 21 19 16 22:00 6 134 168
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
December 10, 2025
Notable earthquakes and events:
The geomagnetic field continued at quiet levels throughout December 9, 2025.
Planetary A-values reached 5 with no peaks in activity recorded. A moderate
geomagnetic storm alert for this time was issued by SWPC but has been cancelled.
However a geomagnetic storm of moderate intensity is expected late on December
10 and into early December 11, 2025. Sudden commencement of this storm could
provoke a moderate earthquake in the region of Alaska which will be near local
solar noon if it arrives as expected. Otherwise seismicity for the coming
day is likely to remain unremarkable.
A moderate earthquake of M 5.5 also occurred today in Northern Colombia.
EMSC reported this earthquake in Colombia was felt with moderate to strong intensity
in Colombia at San Gil, Giron, Bucaramanga, Simacota, Charala, Paipa, Cucuta, Tunja, La Belleza, Gachancipa, Tocancipa, Cajica, Chia, Barrio San Luis, Cota, Funza, Bogota, Mosquera, Soacha, Medellin, Envigado, Itagui, Sabaneta, Caldas, Ricaurte, Ibague, Calarca, Armenia, Cartago.
This earthquake occurred near local solar midnight and may have been promoted
by tidal and/or geomagnetic effects which maximize near this hour.
The last earthquake of M>=5.5 within about 200 km of today's epicenter
was recorded by NEIC as occurring on March 10, 2015 with M 6.2. At the time
this summary noted:
"A strong earthquake of M 6.2 hit at an intermediate depth near Bucaramanga, Colombia today.
It was widely felt in the area of northern Colombia. EMSC reported moderate intensity
in Bucaramanga, Colombia, San Gil, Bogota, Copacabana, Soacha, Bello, El Retiro, Medellin, Sabaneta, La Estrella, Manizales, Cali, Colombia.
NEIC reported intensity V in San Jose de Miranda, Soacha, Pasca, Madrid, Chia, Leiva, and La Ceja, Colombia. Intensity IV was felt in Venezuela at San Cristobal, and II-III in Caracas, Chacao, Ejido, Trujillo, Maracaibo, Venezuela. It was also felt with intensity IV in Envigado, Guarne, Medellin, Barranquilla, Bogota, Chinchina, Manizales, Neira, Cota, La Calera, Puerto Salgar, Tabio, Villavicencio, Funza, LLa Calera, Puerto Salgar, Tabio, Floridablanca, Jordan, Florian, Piedcuesta and II-III in Calif, Sabana de Torres, Puerto Parra, Barrancabermeja, Salento, Armenia, Tiba, Puerto Santander, El Zulia, Fuente de Oror, Santa Maria, Aracataca, Sibato, San Bernardo, Medina, La Mesa, Cajica, Agua de Dios, Yopal, San Luis de Gaceno, Cartagena, Puerto Colombia, Sabaneta, Rionegro, La Union, Barbosa, Colombia.
Some structural damage was reported from Bogota including at City Hall. Air traffic
was briefly disrupted at Manizales where volcanic ash was in the atmosphere.
While residents fled into the streets during the quake, there were no injuries reported.
As often occurs cell phone networks were temporarily down after the quake. Over
use of these networks after an earthquake often occurs as people call others
to check on their status. The volcano Vallerica in Southern Chile continued
an eruption which began on March 4 and has caused extensive evacuation of more than 3000 residents of that
region. This may also have been related to recent solar activity including an
M8.2 flare which occurred hours earlier and the tidal effects of the full moon which
can often affect volcanism.
The earthquake in Colombia was probably promoted by strong solar flares which
occurred today. ...
The last earthquake of M>=6.2 within 150 km of this epicenter occurred
more than 25 years ago. The last event of M>=6.2 in this area was an M 6.2
on June 2, 1988. The last of larger magnitude was an M 6.5 on August 30, 1973
and nearly 50 years ago on July 29, 1967." (March 11, 2015)
Like previous significant earthquakes in this area of Colombia, this event
appears to have been promoted by a solar flare as it occurred near the end of solar
flare 3900 (M1.9), the strongest flare of the past two days. Data for this
flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3900 0731 0737 0800 M1.9 (December 10, 2025) 8.2E-03 *
Northern Colombia M 5.5 08:27 UT
Northern Sumatra M 4.9 07:42 UT
Mindanao M 3.4 07:41 UT
This epicenter is at the third node (120 degrees) from Hokkaido and at the fifth
node (72 degrees) from Yukon, Canada and 105 degrees from Kamchatka and may have been
promoted by energy from those sources.
O: 10DEC2025 08:27:07 6.8N 73.0W MW=5.5 EMSC NORTHERN COLOMBIA
Antipodal activity is common with earthquakes in this region of Colombia. The
most likely antipodal events would be at 6S 106E in the Sumba Strait area of Indonesia.
This area is active at this time and an M 4.1 occurred at this antipodal epicenter
earlier in the day as:
O: 09DEC2025 16:56:43 6.1S 105.8E ML=4.1 EMSC SUNDA STRAIT, INDONESIA
This epicenter is located near the sixth node (60 degrees) from Hokkaido and
at 107 degrees from Yukon Canada and may have been promoted by energy from thoses
sources.
A series of earthquakes occurred today near the sixth node (60 degrees) from the
M 7.6 of Hokkaido, Japan of December 8. These included the two largest earthquakes in
North America (outside Yukon, Canada aftershocks). These were located as an M 3.9
in Vancouver Island, B.C. Canada and off the coast of Oregon as an M 4.1.
Other events near the sixth node from Hokkaido today included an M 3.6 in Gujarat, India;
and moderate earthquakes in Southwestern Siberia (M 4.4), Afghanistan (M 4.5); Java and Santa Cruz Islands (M 4.7) and Sumatra (M 5.2).
The earthquake off Oregon is located at the sixth node (50 degrees) from Hokkair and
at the eighth node from Kamchatka and may have been promoted by energy from those
sources.
O: 09DEC2025 15:12:46 44.5N 129.4W MB=4.1 EMSC OFF COAST OF OREGON
The earthquake in Vancouver is located at the sixth node (50 degrees) from Hokkaido and
near the eighth node from Kamchatka and may have been promoted by energy from those
sources.
O: 10DEC2025 04:43:57 49.6N 127.9W ML=3.9 EMSC VANCOUVER ISLAND, CANADA REGIO
EMSC reported an earthquake of M 5.2 in Atacama, Chile was felt with intensity up to IV in the area(s) of Atacama, Chile in Coquimbo and Vicuna.
This epicenter is located at 104 degrees from the Yukon, Canada and may have
been promoted by energy from that source.
O: 10DEC2025 06:38:10 28.9S 71.2W MW=5.2 EMSC ATACAMA, CHILE
EMSC reported an earthquake of M 5.1 in Sumatra, Indonesia was felt with intensity up to IV in the area(s) of Sumatra, Indonesia in Lubukbergalung.
This epicenter is at 104 degrees from the Yukon; near the fifth node from Kamchatka
and near the sixth node from Hokkaido and may have been promoted by energy
from those sources.
O: 09DEC2025 19:48:27 0.8S 100.9E MB=4.9 EMSC SOUTHERN SUMATRA, INDONESIA
EMSC reported an earthquake of M 4.5 in Iran-Iraq border was felt with intensity up to IV in the area(s) of Iran-Iraq border in Tabriz, Iran and As Sulaymaniyah and Kelar, Iraq.
A similar earthquake of M 4.5 occurred north of this epicenter in northwestern Iran
about 14 seconds later. This is not sufficient time for seismic waves to
have arrived at the second epicenter which is about 403 degrees northeast
of the first epicenter. A similar earthquake of M 4.5 occurred north of this epicenter in northwestern Iran
about 14 seconds later. This is not sufficient time for seismic waves to
have arrived at the second epicenter which is about 403 degrees northeast
of the first epicenter. Travel time curves show the first wave to arrive
were the p-phases which would have arrived one minute and 5 seconds after
the first quake in the Iran-Iraq border.
A hypothesis for the coincidence of these two quakes in Iran involves
triggering by Solar Flare Effects (SFE). In this case a C3.8 solar flare
(#3620) peaked within about one minute of these two Iranian quakes.
It is likely it helped promote these events at this time. Data from
SWPC for this event follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3620 1710 1715 1718 C3.8 (December 9, 2025) 2.8E-03
Iran M 4.5 17:16 UT
Iran-Iraq M 4.5 17:16 UT
These epicenters are located at the fifth node (72 degrees) from the M 7.6 in
Hokkaido and from Kamchatka and the central Philippines and were likely promoted by energy from that source.
O: 09DEC2025 17:16:06 34.3N 45.5E MB=4.5 EMSC IRAN-IRAQ BORDER REGION
O: 09DEC2025 17:16:20 37.7N 47.1E ML=4.5 EMSC NORTHWESTERN IRAN
EMSC reported an earthquake of M 4.6 in Siberia, Russia was felt with intensity up to IV in the area(s) of Siberia, Russia in Gorno-Altaysk and Biysk.
O: 09DEC2025 10:36:50 50.6N 87.3E MB=4.4 EMSC SOUTHWESTERN SIBERIA, RUSSIA
EMSC reported an earthquake of M 4.2 in eastern Turkey was felt with intensity up to IV in the area(s) of eastern Turkey in Erzincan.
This epicenter is at the fifth node (72 degrees) from Kamchatka and from the M 7.6 in Hokkaido Japan of December 8
and may have been promoted by energy from those sources.
O: 09DEC2025 12:34:14 39.5N 39.9E ML=4.2 EMSC EASTERN TURKEY
SEISMIC EFFECTS OF TROPICAL CYCLONES
No tropical cyclones are currently active.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of December 9, 2025. These listings are published daily in this summary and at SWPC.
The main line gives details of flares. Subsequent lines identify some earthquakes
which are at or after the time of the flare and could have been affected by
immediate Solar Flare Effects (SFE). Some earthquakes occur at longitudes
which were at local solar noon or local solar midnight and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3900 0731 0737 0800 M1.9 (December 10, 2025) 8.2E-03 *
Northern Colombia M 5.5 08:27 UT
Northern Sumatra M 4.9 07:42 UT
Mindanao M 3.4 07:41 UT
3300 0019 0030 0037 C4.6 (December 9, 2025) 4.5E-03
Hokkaido M 4.9 00:18 UT
3350 0037 0058 0117 M2.0 (December 9, 2025) 3.7E-02
Kermadec Is. M 5.3 00:37 UT
3360 0134 0138 0142 M1.1 (December 9, 2025) 6.0E-03
3370 0147 0152 0155 C8.0 (December 9, 2025) 4.1E-03
Coquimbo M 4.0 01:57 UT
3400 0234 0236 0239 C2.5 (December 9, 2025) 8.8E-04
3470 0532 0539 0543 C3.1 (December 9, 2025) 1.8E-03
Oaxaca M 4.1 05:36 UT
Antofagasta M 4.3 05:46 UT
Trinidad-Tobago M 3.6 05:31 UT
3500 0741 0747 0751 M1.6 (December 9, 2025) 1.2E-02
Afghanistan M 4.5 07:47 UT
Chiapas M 4.0 07:49 UT
3530 0956 1004 1008 C4.2 (December 9, 2025) 2.5E-03
Iceland M 5.0 12:12 UT
Hokkaido M 3.3 10:04 UT
3550 1129 1142 1148 C2.7 (December 9, 2025) 3.3E-03
Santa Cruz Is. M 4.7 11:26 UT
3570 1235 1241 1255 C3.9 (December 9, 2025) 4.7E-03
Antofagasta M 4.0 12:57 UT
3580 1315 1325 1327 C4.8 (December 9, 2025) 4.6E-03
3580 1327 1335 1343 C5.6 (December 9, 2025) 5.6E-03
Java M 4.0 13:43 UT
3600 1500 1514 1520 M1.5 (December 9, 2025) 1.0E-02
Oregon M 4.1 15:13 UT
Sulawesi M 4.0 15:20 UT
3620 1652 1702 1710 C3.7 (December 9, 2025) 4.1E-03
Sunda Strait, M 4.1 16:56 UT
3620 1710 1715 1718 C3.8 (December 9, 2025) 2.8E-03
Iran M 4.5 17:16 UT
Iran-Iraq M 4.5 17:16 UT
3620 1718 1724 1727 C3.8 (December 9, 2025) 2.5E-03
3650 1851 1912 1931 C3.9 (December 9, 2025) 8.7E-03
Hindu Kush M 4.2 19:00 UT
Argentina M 4.1 19:14 UT
3670 2053 2109 2121 C3.4 (December 9, 2025) 5.1E-03
Kermadec M 5.3 21:00 UT
3680 2130 2142 2203 C5.0 (December 9, 2025) 8.8E-03
Timor M 4.0 21:51 UT
3690 2232 2238 2243 C3.7 (December 9, 2025) 2.3E-03
3700 2313 2327 2336 M1.5 (December 9, 2025) 1.3E-02
Kuril Is. M 4.5 23:19 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms December 10 disturbed December 11-12. Solar M-flare chance: 65% X-class: 15% proton storm: 15%
AP Indicies (global, high, mid-latitude, time of max AP, Max AP, Sunspot Number, Radio Flux) 5 5 4 11:00 3 134 183
A strong Gamma Ray Burst was recorded by SWIFT on December 5, 2025 at 23:39:47 UT (#251205A). A preliminary UVOT Magnitude of V=17.10 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on December 1, 2025 at 16:26:30 UT (#251201B). A preliminary UVOT Magnitude of V=15.97 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 26, 2025 at 19:10:36 UT (#251126A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 12, 2025 at 21:28:56 UT (#251112A). A preliminary UVOT Magnitude was not assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on November 3, 2025 at 16:46:36 UT (#251103B). A preliminary UVOT Magnitude of V>19.0 was assigned to this GRB.
A strong Gamma Ray Burst was recorded by SWIFT on October 24, 2025 at 17:47:02 UT (#251024A). A preliminary UVOT Magnitude of V>18.0 was assigned to this GRB.
Print 