May 19, 2026
Notable earthquakes and events:
Mount Mayon in Luzon, Philippines re-energized the volcanic eruption that began
last week. The eruption today sent ash to 13,000 feet and coated nearby towns
in ash and caused evacuations. Lava has flowed since the eruption began
and is likely to continue, perhaps at an accelerated rate.
Mount Mayon is located at 13.3N 123.7E. The current eruption began when
Mount Mayon was at a sub-solar latitude (13.3 north latitude on May 10).
Sub-solar conditions occur when the sun is directly overhead at local solar
noon (LSN). Vertical tidal stresses are maximized at this time and often
result in enhanced volcanism and earthquakes near sub-solar conditions as
previous hypothesized in this summary.
Seismic areas that are currently at sub-solar latitudes (near 15-16 North latitude)
include Guatemala and Mexico, the Gulf of Aden, Southern Myanmar and the Andaman Islands, and central Luzon and Guam.
Enhanced seismicity and/or volcanism is likely at this time in these areas due to this effect.
NEIC reported an earthquake of M 5.2 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar at Syriam, Rangoon and in Thailand at Chiang Mai and Bankok with intensity II.
EMSC reported strong shaking in Myanmar at Syriam, Yangon.
It is of some interest that this epicenter at 16.4 North latitude was
nearly sub-solar when it occurred. Sub-solar events occur when the
sun is directly overhead at local solar noon (LSN). Vertical tidal
stresses are maximized at this time and can help promote enhanced seismicity.
Latitudes that are sub-solar on May 18 are around 15-16 degrees North Latitude.
This epicenter is at the fifth node (72 degrees) from the North Geomagnetic
Pole and was probably promoted by concentrated effects at that source due
to the strong geomagnetic storm of the past several days.
O: 18MAY2026 02:05:24 16.4N 96.3E ML=5.2 NEIC MYANMAR
O: 18MAY2026 02:05:23 16.5N 96.4E MW=5.2 EMSC NEAR SOUTH COAST OF MYANMAR
A minor fluctuation in geomagnetic field strength occurred at 05:07 UT as recorded on the GOES-19 magnetometers.
An M 4.7 in southern Xinjiang, China at 05:07 UT was coincident with
this geomagnetic excursion. An arcjet correction to the orbit returned
the system to normal operations by 06:49 UT. This geomagnetic excursion was also associated with an M 4.1 in Chiapas, Mexico at 05:08 UT and an M 4.3
in the Dodecanese Islands of Greece at 05:11 UT.
The strongest earthquake in the world today was an M 5.7 in southern Vanuatu.
NEIC reported it was felt with intensity IV in Vanuatu at Vila Shefa, 61 km from the
epicenter. EMSC reported a rumble was heard with the quake in Port-Vila, Vanuatu. The last earthquake within about 200 km of this event in Vanuatu
with M>=5.7 occurred as an M 6.1 about 100 km to the south of this on March 20, 2026.
At the time this summary noted:
"NEIC reported an earthquake of M 6.1 in Southern Vanuatu was felt with intensity up to II-III in the area(s) of Southern Vanuatu with IV near Isangel.
EMSC reported it was felt lightly in Vanuatu in Port-Vila and in New Caledonia at Noumea.
This earthquake occurred near local solar noon in this area and was probably
promoted by tidal effects related to the new moon of March 19 (see above) as
it occurred near the longitude of maximum stress with that alignment.
This epicenter is at 105 degrees from the North Geomagnetic Pole; at the sixth node
from Malaysia (60 degrees) and the fifth node (52 degrees) from Kamchatka and
may have been promoted by energy from those sources." (March 20, 2026)
It may be of interest that this event in March, 2026 apparently was promoted
by the beginning of the last strong geomagnetic storm which commenced
early on March 20, 2026. At the time this summary noted it as:
"The expected geomagnetic storm arrived ... on UT March 20 and early on UT March 21.
This storm reached planetary K-index of 7 from 21:00 on March 20 to 04:00 on
March 21. This is a G3 geomagnetic storm and could cause problems
with space-based communications and ground based electrical systems on the sunlit side
of the earth. The storm arrived about 20:45 UT on March 20 with a major increase near
23:00 UT (as seen on GOES-18 magnetometer). Areas at local solar noon at this time are near the IDL and include
Vanuatu, New Zealand, Tonga, Fiji, Western U.S. and Alaska with local solar
midnight in Central Europe, Italy, and Greece and the Atlantic Ocean among others.
These are the most likely areas to see enhanced seismicity associated with
the sudden commencement of this storm. In the previous issues of this summary
the expected action of this geomagnetic change with this storm had been noted as:
"A CME is headed directly towards earth and is expected to arrive on March 19 UT.
This may combine with several other CMEs currently heading towards earth. SWPC
had predicted a major geomagnetic storm is likely on March 19. The strength
of this storm would probably be in the G2-G3 range and could adversely affect
satellites and electrical systems on the sunlit side of the earth at commencement.
It may be enhanced as it is occurring at the Spring Equinox (on March 20). At Spring
Equinox the earth's orientation in space is such that the sun is directly overhead
at the equator. At this time magnetic fields are oriented in such a way that
they connect with geomagnetic storms from the sun with greater than usual
strength. This is called the Russell-McFaren effect and has been documented
many times since its discovery in 1973. Geomagnetic storms tend to be larger
at spring and fall equinoxes because of this effect (March 20 and September 20).
Combine this with the new moon and effects on the earth could be substantial.
Watch for the commencement time of this geomagnetic storm today or tomorrow.
Areas near local solar noon and local solar midnight are the most likely
to see seismic enhancement at or within several hours atter commencement. This
strom may have begun around 08:00-10:00 UT on March 19. Plasma Density near earth increased by fivefold
at this time and radial velocity of plasma increased by 20% at this time.
This coincided with an M 5.6 in the Kuril Islands. That epicenter in the Kurils
was at local solar noon when the new moon arrived today and was probably
promoted by tidal stresses with the new moon. The effects of the new moon on seismicity have previously been noted in this
summary." (March 18-21, 2026)
Today's event in Vanuatu also occurred near 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 from the South Geomagnetic Pole (51 degrees)
and from the North Geomagnetic Pole (104 degrees) and may have been promoted
by the recent geomagnetic storm which effects concentrate at those locations.
Constructive interference of energy from the poles is likely to have
helped promote this earthquake in Vanuatu today.
O: 19MAY2026 02:29:24 18.2S 168.1E ML=5.7 NEIC VANUATU
O: 19MAY2026 02:29:25 18.2S 168.1E MW=5.7 EMSC VANUATU
NEIC reported an earthquake of M 3.5 near Oklahoma City, Oklahoma was felt with intensity up to II-III in the area(s) of near Oklahoma City, Oklahoma with intensity IV in Oklahoma at Tecumseh, Shawnee, McLou and III in Norman, Seminole, Harrah, Wewoka, Prague and Choctaw.
EMSC reported it occurred with a loud thunderous noise in Oklahoma at Shawnee and Yukon.
This event occurred within minutes of locals solar midnight and may have
been promoted by tidal and/or geomagnetic effects which maximize near this
hour.
This epicenter is at the fourth node (90 degrees) from Tonga and at 103 degrees from
Vanuatu and may have been promoted by energy from those sources.
O: 19MAY2026 06:47:52 35.4N 96.8W ML=3.5 NEIC OKLAHOMA
O: 19MAY2026 06:47:52 35.4N 96.8W ML=3.3 EMSC OKLAHOMA
NEIC reported an earthquake of M 2.8 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii in Kailua Kona.
O: 19MAY2026 03:42:51 19.2N 155.5W ML=2.8 NEIC HAWAII
The strongest earthquake in the U.S. or Canada today was an M 4.9 in the eastern Andreanof Islands, Alaska.
NEIC reported it may have been felt in Atka, Alaska.
These epicenters area near the fifth node (72 degrees) from Tonga, Malaysia, Vanuatu and
the Molucca Sea and may have been promoted by constructive energy interference
from those sources.
O: 18MAY2026 21:37:20 52.4N 171.8W ML=4.9 NEIC ANDREANOF ISLANDS, ALASKA
O: 18MAY2026 21:37:20 52.5N 171.8W MW=4.9 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 18MAY2026 23:27:41 52.4N 171.6W ML=3.4 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
NEIC reported an earthquake of M 5.3 in the Bouvet Island region of the South Atlantic was was not felt in this remote area.
This epicenter is antipodal to the Rat Islands swarm of last week. An M 5.8
hit at the antipode of Bouvet Island on May 9, 2026 in the Rat Islands.
Antipodal pairs are not uncommon in these two locations.
This epicenter is near 110 degrees from Tonga, Malaysia, Vanuatu and the Molucca Sea
and may have been promoted by constructive interference of energy from
those sources. It is also at 147 degrees from the North Geomagnetic Pole
and near the sixth node from the South Geomagnetic Pole and may have
been promoted by the recent geomagnetic storm which concentrated energy
at the geomagnetic poles.
O: 18MAY2026 18:50:00 54.2N 1.3W ML=5.3 NEIC BOUVET ISLAND REGION
O: 18MAY2026 18:50:00 54.2S 1.3W MB=5.3 EMSC BOUVET ISLAND REGION
NEIC reported an earthquake of M 3.2 in Central California was felt with intensity up to II-III in the area(s) of Central California in Santa Margaria and Bakersfield.
This epicenter is at the fifth node (2 degrees) from Honshu, Japan and
may have been promoted by energy from that source. It is also near the
seventh node (52 degrees) from the North Geomagnetic Pole and may have
been promoted by energy related to the recent geomagnetic storm.
O: 18MAY2026 15:54:36 35.8N 119.9W ML=3.2 NEIC CENTRAL CALIFORNIA
O: 18MAY2026 15:54:34 35.8N 119.8W ML=3.0 EMSC CENTRAL CALIFORNIA
O: 18MAY2026 17:15:06 35.8N 119.8W MD=2.2 EMSC CENTRAL CALIFORNIA
NEIC reported an aftershock of M 5.1 in Liuzhou, China was felt with intensity up to II-III in the area(s) of Liuzhou, China in Guangxi with V in Liuzhou; III in Pumiao, Guilin and II in Nanning.
EMSC reported scary motion in China at Liuzhou, Guilin, Yangshuo, Nanning and in Vietnam at Hoan Kiem.
This is an aftershock of the M 5.2 yesterday which was described (in part)
in the previous issue of this summary as:
"The most notable earthquake in the world today was an M 5.2 in southern China.
NEIC reported intensity IV in Guangxi, China at Liuzhou and III in Nanning, Guilin, Hechi and Pumiao.
The only earthquake in the past 35 years within about 200 km of this epicenter in Guangxi with
M>5.0 was reported on March 30, 2015 with M 5.4. At the time this summary noted:
"NEIC reported this earthquake of M 5.4 in Guizhou, China was felt with intensity II-III in the area(s) of Guilin, Guangxi, China.." (March 30, 2015)
On November 24, 2021 and M 4.9-5.0 quake hit the region and was noted as:
"NEIC reported this earthquake of M 5.0 in Guizhou, China was felt with intensity II-III in the area(s) of Guizhou, China at Guiyang and Zunyi." (November 24, 2021)
The M 5.0-5.2 was accompanied by a series of minor foreshocks and aftershocks. The sequence was considered
especially significant due to its intensity, and impact on concentrated
populated areas. The epicenter was located near Taoshan Village in Liunan District.
Press reports indicated that at least 13 buildings collapsed in this shallow
focus earthquake. At least two people were killed and several other injured in the
quake. More than 7000 people were evacuated but many were still missing among continuing rescue operations.. People fled their homes during the shaking and gathered
in small crowds in the streets. Landslides and regional chaos were common
following and during the earthquake. Internet videos of the shaking were common
and showed extensive damage in the area. This earthquake occurred within
minutes of local solar midnight and may have been promoted by tidal
stresses with the new moon of May 16 and/or geomagnetic effects which
maximize near this hour. Previous issues of this summary had expected new moon tidal effects
on seismicity as:
"The new moon will arrive on May 16, 2026 at 20:01 UT. Longitudes which are at local solar noon at this time are near 120W and those at local solar midnight near 60E. In the west these include western North America (including California, Oregon and Washington) 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." (May 14-17, 2026)
This earthquake in China follows the strongest geomagnetic storm in the
past two months and is at 90.0 degrees (node 4) from the Southern Geomagnetic
Pole. It was probably promoted by energy concentrated at that source
during the geomagnetic storm." (May 17-18, 2026)
O: 18MAY2026 13:44:26 24.5N 109.2E ML=5.1 NEIC LIUZHOU, CHINA
O: 18MAY2026 13:44:26 24.5N 109.2E MW=5.1 EMSC GUANGXI, CHINA
NEIC reported an earthquake of M 3.0 in Southern Colorado was felt with intensity up to II-III in the area(s) of Southern Colorado in Walsenburg.
Like the M 3.2 in Central California (see above) it is also near the
seventh node (52 degrees) from the North Geomagnetic Pole and may have
been promoted by energy related to the recent geomagnetic storm.
O: 18MAY2026 12:29:54 37.6N 104.7W ML=3.0 NEIC SOUTHERN COLORADO
O: 18MAY2026 12:29:54 37.6N 104.8W ML=3.0 EMSC COLORADO
NEIC reported an earthquake of M 4.7 in northern Chile was felt with intensity up to II-III in the area(s) of northern Chile with IV in Iquique, Tarapaca.
EMSC reported strong shaking in Chile at Iquique and Arica.
O: 18MAY2026 08:48:06 20.5S 70.2W ML=4.7 NEIC NORTHERN CHILE
O: 18MAY2026 08:48:05 20.5S 69.9W MB=4.7 EMSC TARAPACA, CHILE
The series of light earthquakes in southern California near Ocotillo Wells, California also continued today
in an area of the Coachella Valley about 40 km northwest of the swarm
in the area last week. This area had been watched by seismologists as
a possible precursor to a larger earthquake along the southern San Andreas
fault. The swarm today began within minutes of local solar midnight (LSM)
and intensified near LSM with an M 3.1 event. For a fuller discussion of
this swarm readers are referred to the previous issue of this summary.
O: 18MAY2026 07:55:18 33.1N 115.9W ML=3.1 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 07:30:23 33.1N 115.9W ML=2.5 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 07:30:22 33.1N 115.9W ML=2.5 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 07:55:18 33.1N 115.9W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:00:14 33.1N 115.9W ML=2.1 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:03:30 33.1N 115.9W ML=2.2 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:10:53 33.1N 115.9W ML=2.4 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:16:13 33.1N 115.9W ML=2.1 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:17:20 33.1N 115.9W ML=2.2 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:25:22 33.1N 115.9W ML=2.4 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 08:27:29 33.1N 115.9W ML=2.8 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 09:01:00 33.1N 115.9W ML=2.0 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 09:01:54 33.1N 115.9W ML=2.3 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 09:47:47 33.1N 115.9W ML=2.5 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 09:57:12 33.1N 115.9W ML=2.3 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 11:17:40 33.1N 115.9W ML=2.0 EMSC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 2.1 in Greater Los Angeles, California was felt with intensity up to IV in the area(s) of Greater Los Angeles, California as a strong jolt in Bellflower, Lakewood, Parmount, Norwalk, Downey.
O: 18MAY2026 18:02:51 33.8N 118.1W ML=2.1 EMSC GREATER LOS ANGELES, CALIFORNIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 18, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3870 0319 0329 0334 B8.3 (May 18, 2026) 6.7E-04
3920 1810 1828 1845 C1.9 (May 18, 2026) 2.8E-03
Bouvet Is M 5.3 18:50 UT
3930 1948 2000 2007 B6.6 (May 18, 2026) 6.4E-04
Sumatra M 4.0 19:52 UT
GEOMAGNETIC FIELD: minor storms May 19 quiet May 20 unsettled May 21. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 9, high: 19, mid-latitude: 8, time of max k: 15:00 UT; Max k: 5 Global Kp 2.67 2100-2400, May 18; Sunspot Number: 77; Radio Flux: 105
May 18, 2026
Notable earthquakes and events:
The geomagnetic storm continued today with electron flux at satellite altitudes
above the SWPC Alert Threshold throughout the day. A slight enhancement in Proton flux
occurred mid-day on UT May 17. AP and k-indices did not reflect this storm
staying below G1 storm levels throughout the day. A minor fluctuation in
geomagnetic field strength occurred at 05:07 UT as recorded on the GOES-19 magnetometers.
An M 4.7 in southern Xinjiang, China at 05:07 UT was coincident with
this geomagnetic excursion. An arcjet correction to the orbit returned
the system to normal operations by 06:49 UT. This geomagnetic excursion was also associated with an M 4.1 in Chiapas, Mexico at 05:08 UT and an M 4.3
in the Dodecanese Islands, of Greece at 05:11 UT.
The most notable earthquake in the world today was an M 5.2 in southern China.
NEIC reported intensity IV in Guangxi, China at Liuhou and III in Nanning, Guilin, Hechi and Pumiao.
The only earthquake in the past 35 years within about 200 km of this epicenter in Guangxi with
M>5.0 was reported on March 30, 2015 with M 5.4. At the time this summary noted:
"NEIC reported this earthquake of M 5.4 in Guizhou, China was felt with intensity II-III in the area(s) of Guilin, Guangxi, China.." (March 30, 2015)
On November 24, 2021 and M 4.9-5.0 quake hit the region and was noted as:
"NEIC reported this earthquake of M 5.0 in Guizhou, China was felt with intensity II-III in the area(s) of Guizhou, China at Guiyang and Zunyi." (November 24, 2021)
The M 5.0-5.2 was accompanied by a series of minor foreshocks and aftershocks. The sequence was considered
especially significant due to its intensity, and impact on concentrated
populated areas. The epicenter was located near Taoshan Village in Liunan District.
Press reports indicated that at least 13 buildings collapsed in this shallow
focus earthquake. At least two people were killed and several other injured in the
quake. More than 7000 people were evacuated but many were still missing among continuing rescue operations.. People fled their homes during the shaking and gathered
in small crowds in the streets. Landslides and regional chaos were common
following and during the earthquake. Internet videos of the shaking were common
and showed extensive damage in the area. This earthquake occurred within
minutes of local solar midnight and may have been promoted by tidal
stresses with the new moon of May 16 and/or geomagnetic effects which
maximize near this hour. Previous issues of this summary had expected new moon tidal effects
on seismicity as:
"The new moon will arrive on May 16, 2026 at 20:01 UT. Longitudes which are at local solar noon at this time are near 120W and those at local solar midnight near 60E. In the west these include western North America (including California, Oregon and Washington) 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." (May 14-17, 2026)
This earthquake in China follows the strongest geomagnetic storm in the
past two months and is at 90.0 degrees (node 4) from the Southern Geomagnetic
Pole. It was probably promoted by energy concentrated at that source
during the geomagnetic storm.
O: 17MAY2026 16:21:06 24.4N 109.2E ML=5.0 NEIC LIUZHOU, CHINA
O: 17MAY2026 16:21:05 24.5N 109.3E ML=5.1 EMSC GUANGXI, CHINA
O: 17MAY2026 16:21:05 24.5N 109.3E ML=5.2 CENC GUANGXI, CHINA
A series of light earthquakes in southern California near Ocotillo Wells, California also occurred today
in an area of the Coachella Valley about 40 km northwest of the swarm
in the area last week. This area had been watched by seismologists as
a possible precursor to a larger earthquake along the southern San Andreas
fault. The swarm today began within minutes of local solar midnight (LSM)
and intensified near LSM with an M 3.1 event. When the swarm to the southeast
occurred this summary noted the potential for this further activity as:
"The M 5.0 earthquake off the coast of northern California yesterday (see previous issue)
occurred near the northern terminus of the San Andreas Fault in California.
It was followed by an M 4.7 and a number of other moderate and light earthquakes
in Southern California near Brawley near the southern terminus of the
San Andreas Fault. This suggests a connection between these two events
through the San Andreas Fault system. The earthquake off northern California
was apparently triggered by seismic waves from the M 5.8 earthquake in
the Rat Islands 15-16 minutes earlier (see previous analysis in this
summary. This suggest the entire system of faults is near rupture and
that a strong earthquake on this system is near. An M 2.7 following the M4+ solar flare (see above) near local
noon today in San Francisco, California may indicate one of the areas
where stress is high and a moderate quake could occur under the right
environmental conditions. Over the past months a consistent pattern of
light to moderate earthquakes in this area near local solar noon or midnight
has suggested triggering from tidal and/or geomagnetic environmental effects.
As noted in the previous summary, the M 5.0 off northern California occurred as several seismic
waves were passing through the are which originated with an M 5.8 in the Rat
Islands, Alaska. The triggering relation between these events was strengthened
when an M 4.4 aftershock in the Rat Islands occurred today was the S-phase
from Southern California was in the area of the epicenter in the Rat Islands
slightly more than 17 minutes later. Aftershocks continued today in the Brawley area of Southern California. Some
of these were lightly felt. In the previous issue of this summary this
swarm had been addressed as:
"A moderate earthquake of M 4.7 near Brawley, Southern California joined a number of light foreshocks
and aftershocks today in the area. NEIC reported the mainshock which occurred
local solar midnight may have caused slight damage with intensity VI in Brawley, California
with IV in Holtville, Imperial, Calipatria, Vista and III in San Diego, El Cajon, El Centro and La Mesa and in Cibola, Arizona.
Other moderate quakes in the series included events of M 4.5 and M 4.0 as foreshocks of the M 4.7.
Earthquakes in this area are often associated with swarms with larger earthquakes
in the middle of the sequence so additional activity in this swarm is expected
today and tomorrow.
This is an area which had been expected to see enhanced seismicity at this time as noted in the previous issue
of this summary.
"An M 3.1 in Baja and Southern California at 22:13 UT also occurred
and may indicated instability in that area leading to enhanced seismicity
in the next day or so." (May 8-10, 2026)
and
"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 with III in Ramona, Valley Center and II in Escondido, Descanso, Warner Springs, Poway, and Menifee.
This event occurred near local solar noon and was floowed by a series of events to the
southeast of M 3.4 and 3.6 in Baja, California and M 3.2 in the Gulf of California
in the next several minutes. This is not part of the series of events near Brawley two days ago as it occurred
about 50 km northwest of that on the San Andreas. It may represent a potentially
dangerous migration of stress along the fault to the northwest, however, so
the area should be continually monitored at this time." (May 14, 2026)
A possible M 2.7 foreshock occurred yesterday west of today's swarm in
southern California and was noted in this summary at the time as:
"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 in San Diego.
O: 16MAY2026 08:28:04 33.0N 116.3W ML=2.7 NEIC SOUTHERN CALIFORNIA " (May 17, 2026)
O: 18MAY2026 07:55:18 33.1N 115.9W ML=3.1 EMSC SOUTHERN CALIFORNIA
O: 18MAY2026 07:30:23 33.1N 115.9W ML=2.5 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 5.2 in the Mid-Indian Ridge wasn not felt in this remote
area. It occurred within minutes of local noon and may have been promoted
by tidal and/or geomagnetic effects which maximize near this hour.
The antipode is in the northern Gulf of California near 28N 106W - an area
which could see enhanced seismicity at this time. The swarm in the Ocotillo,
Wells area of California (see above) followed this event in the Indian Ocean
with an M 3.1 starter 21 minutes later. The distance between these two
is near antipodal at 170 degrees. Travel time curves show the core reflected wave
PKP from the Indian Ocean was at the epicenter in Southern California when
that swarm began and may have helped promote it.
This epicenter was probably promoted by the strong geomagnetic storm of the
past two days. It is located ath the seventh node (52 degrees) from the South
Geomagnetic Pole and at the third node (120 degrees) from the North Geomagnetic
pole where geomagnetic effects concentrate during geomagnetic storms.
O: 18MAY2026 07:34:30 28.5S 74.3E ML=5.2 NEIC MID-INDIAN RIDGE
O: 18MAY2026 07:34:30 28.5S 74.3E MB=5.2 EMSC MID-INDIAN RIDGE
NEIC reported an earthquake of M 5.2 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar at Syriam, Rangoon and in Thailand at Chiang Mai and Bankok with intensity II.
EMSC reported strong shaking in Myanmar at Syriam, Yangon.
It is of some interest that this epicenter at 16.4 North latitude was
nearly sub-solar when it occurred. Sub-solar events occur when the
sun is directly overhead at local solar noon (LSN). Vertical tidal
stresses are maximized at this time and can help promote enhanced seismicity.
Latitudes that are sub-solar on May 18 are around 15-16 degrees North Latitude.
Mount Mayon in Luzon, Philippines re-energized the volcanic eruption that began
last week. The eruption today sent ash to 13,000 feet and coated nearby towns
in ash and caused evacuations. Lava has flowed since the eruption began
and is likely to continue, perhaps at an accelerated rate.
Mount Mayon is located at 13.3N 123.7E. The current eruption began when
Mount Mayon was at a sub-solar latitude (13.3 north latitude on May 10).
Sub-solar conditions occur when the sun is directly overhead at local solar
noon (LSN). Vertical tidal stresses are maximized at this time and often
result in enhanced volcanism and earthquakes near sub-solar conditions as
previous hypothesized in this summary.
Seismic areas that are currently at sub-solar latitudes (near 15-16 North latitude)
include Guatemala and Mexico, the Gulf of Aden, Southern Myanmar and the Andaman Islands, and central Luzon and Guam.
Enhanced seismicity and/or volcanism is likely at this time in these areas due to this effect.
This epicenter is at the fifth node (72 degrees) from the North Geomagnetic
Pole and was probably promoted by concentrated effects at that source due
to the strong geomagnetic storm of the past several days.
O: 18MAY2026 02:05:24 16.4N 96.3E ML=5.2 NEIC MYANMAR
O: 18MAY2026 02:05:23 16.5N 96.4E MW=5.2 EMSC NEAR SOUTH COAST OF MYANMAR
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 in Rio Dell, Ferndale, Fortuna.
O: 17MAY2026 18:49:57 40.3N 124.0W ML=3.2 NEIC NORTHERN CALIFORNIA
O: 17MAY2026 18:49:57 40.4N 124.1W ML=2.9 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.5 in Java, Indonesia was felt with intensity up to II-III in the area(s) of Java, Indonesia in Karawang and Depok.
EMSC reported slight shaking in Bogor, Indonesia.
This epicenter was probably promoted by effects from the strong geomagnetic
storm of the past two days as it is located at the sixth node (60 degrees)
from the South Geomagnetic Pole. It is also near the sixth node from Honshu, Japan
and Vanuatu and may have been promoted by constructive interference of energy from those sources.
O: 17MAY2026 15:14:59 7.2S 106.6E ML=4.5 NEIC JAVA, INDONESIA
O: 17MAY2026 15:15:00 7.3S 106.7E MB=4.5 EMSC JAVA, INDONESIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 17, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3730 0321 0339 0350 M1.4 (May 17, 2026) 5.2E-03 *
Guatemala M 4.0 04:03 UT
New Zealand M 4.5 03:21 UT
3770 0745 0757 0809 B9.0 (May 17, 2026) 1.2E-03
Admiralty Is. M 5.1 07:52 UT
Kuril Is. M 5.7 08:04 UT
3740 0436 0444 0452 C1.0 (May 17, 2026) 9.3E-04
Kuril Is. M 5.3 05:02 UT
3750 0521 0532 0537 C2.0 (May 17, 2026) 1.6E-03
Oaxaca M 4.1 05:21 UT
3780 0810 0818 0821 B7.1 (May 17, 2026) 5.4E-04
Kuril Is. M 5.4 08:04 UT
3790 1123 1132 1140 C1.1 (May 17, 2026) 1.1E-03
3800 1201 1207 1210 C1.0 (May 17, 2026) 5.5E-04
3810 1225 1238 1257 C1.1 (May 17, 2026) 1.9E-03
3840 1807 1816 1822 B8.0 (May 17, 2026) 7.0E-04
Bismarck Sea M 4.4 17:58 UT
3850 2042 2053 2105 C9.7 (May 17, 2026) 7.2E-03
New Britain M 4.8 20:52 UT
GEOMAGNETIC FIELD: minor storms May 18-19 quiet May 20. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 8, high: 17, mid-latitude: 8, time of max k: 12:00 UT; Max k: 5 Global Kp 2.33 1200-1700, May 17; Sunspot Number: 86; Radio Flux: 104
May 17, 2026
Notable earthquakes and events:
The geomagnetic storm which began on May 15 continued through May 16 and early
May 17 at G1 to G2 (strong disturbance levels). The sudden commencement
of this storm coincided with an M 6.7 earthquake off the coast of northern
Honshu, Japan (see previous issues of this summary for more detailed
analysis). The high latitude A-index for May 16 was 60. This is the strongest
geomagnetic storm since high latitude AP reached 92 on March 22, 2026. Electron
Flux passed over the SWPC Alert Threshold about 15:00 UT on May 16, the maximum
commencement for this storm. There was no accompanying proton storm. Several moderately strong to strong earthquakes on May 16, 2026
occurred near the peak times of disturbance with today's geomagnetic storm
but were also (for the most part) also coincident with moderate to strong
solar flares and differentiating the effects of these two triggers can
be difficult. The strongest earthquake in the world today was an M 6.0
in the Antigua and Barbuda area of the eastern Caribbean. This event occurred
near local solar noon with a series of C- and M-class solar flares and
near the height of the geomagnetic storm and was probably triggered by
effects from each of these sources.
An M 6.0 occurred near local solar noon in Antigua and Barbuda in the
Leeward Islands, eastern Caribbean. NEIC reported it was widely felt in the area of the
Virgin Islands and Puerto Rico with III in Puerto Rico at San Juan, II in Guaynabo, Toa Alta, Toa Baja and in the Virgin Islands at Saint Thomas.
EMSC reported strong tremor in Antigua and Barbuda at Cedar Grove, Saint John's with a loud rumble;
also reported felt with moderate intensity in Guadeloupe at Petit-Canal, Le Moule, Saint-Francois, Sainte-Anne,
Sainte-Rose, La-Mentin, Baie-Mahault, Pointe-a-Pitre, Pointe-Norie, La Gosier, Petit-Bourg, Capesterre-Belle.- Eau, Vieux-Habitnats, Grand-Bourg, Baillif, in Saint Kitts and Nevis at Boyd's; in Saint Barthelemy at Gustavia, in onaire, Saint Eustatius and Saba at Golden Rock, in Sint Maarten at Koolbaai, in Martinique at Saint-Joseph, Le Gros-Morne, La Lamentin, Le Francois, Ducos, and Les Trois-Ilets.
The last earthquake within about 200 km of this epicenter with M>=6
occurred as an M 6.0 on March 19, 2016. At the time this summary noted:
The strongest earthquake of the day was an M 6.0 in the Antigua and Barbuda area
of the eastern Caribbean. It was felt with intensity up to V in Antigua and Barbuda
at Carlisle, Saint George; Potters Village, All Saints, and Saint John's, Saint John; in Bolands, Old Road, Saint Mary; in Montserrat at Salem and Saint Johns; in Guadeloupe at Saint-Barthelemy, Saint Claude, Sainte-Rose, Basse-Terre, at Point-a-Pitre, Le Gosier, Baie Mahault, Basse-Terre, La Mentin, Petit Bourg, Guadeloupe;
in Saint Kitts and Nevis at Gingerland, Charlestown, Point-Noire, Caump. Basseterre; in Netherlands Antilles at Princess Quarter, Cherry Tree, Little Bay, Cul De Sac, Simpson Bay and Low Lands; in Dominica at Woodford Hill, Portsmouth, Castle Bruce, Rosalie, Mahaut; in Martinique at Gros-Morne, La Trinite; Le Robert, Le Lamentin, Fort-de-France, Saint-Esprit, Le Marin; in the U.S. Virgin Islands at Saint Thomas; in Saint Lucia at Cap Estate, Laborie, and at Carolina, Puerto Rico, USA.
... The last earthquake of M>=6 within about 150 km of this
epicenter was an M 6.0 about 100 km south of this epicenter on May 16, 2014. The only
other such event in the area in the past 25 years was an M 6.6 on May 14, 2003
about 150 km northeast of today's epicenter." (March 19, 2016)
Today's event in Antigua occurred at the maximum of the geomagnetic storm
(see above) and may have been promoted by effects related to that storm.
A similar geomagnetic storm coincided with the earthquake of March 19, 2016 as
described in this summary at the time:
"The geomagnetic field was at active conditions today. The AP level was 22.
High latitude geomagnetic field was with minor storms with AP at 40.
Seismicity within about 10-15 degrees of the geomagnetic equator and at high latitudes typically increases
in the period 4-6 days after the end of geomagnetic storms. A strong earthquake
in this zone is most likely in the period March 20-25." (March 16-19, 2016)
Moderate to strong earthquakes today near the geomagnetic equator as described
in this forecast included an M 5.5 in Vanuatu and an M 5.4 in Tajikistan. This
is typical seismicity following geomagnetic storms. The earthquake in Vanuatu
is at the fifth node (72 degrees) from the Sumatra event of March 2 and may have
been promoted by energy from that event and/or geomagnetic effects." (March 19, 2016)
Today's earthquake in Barbuda may also have been promoted by a moderate
solar flare, the start of a series as it occurred near the peak of this
flare near local solar noon (flare 3560 C1.1). Data on this flare from
SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3560 1419 1439 1456 C1.1 (May 16, 2026) 2.2E-03
Antigua M 6.0 14:50 UT
Kyrgyzstan M 4.6 14:53 UT
In addition to occurring within an hour of local solar noon, today's
event in Antigua was also nearly sub-solar when it occurred. Sub-solar
events occur when the sun is directly overhead at noon. On the 17th of
May the sub-solar latitude is about 16 degrees north while the Barbuda
epicenter is at 17 degrees north latitude. Vertical tidal effects from the
sun can be amplified in this configuration. This summary has, in the
past emphasized this as for example when a strong sub-solar earthquake
hit Samar, Philippines on May 4 it was noted:
"This earthquake in Samar, Philippines (and the eruption of Mount Mayon) occurred when the sun was directly
overhead at noontime in Samar - that is the epicenter was almost exactly
sub-solar at the time of the earthquake. Vertical tidal stresses from the sun are
maximized at this time and may have helped promote today's event.
The sub-solar latitude on May 4 is 23.5/2 = 11.7 degrees north, exactly
the longitude of the Samar earthquake. It is curious that the strongest
earthquake in Samar in the past 31 years occurred on May 5, 1995 with M 7.1 -
also nearly exactly sub-solar. That event occurred within minutes of local
solar noon when the epicenter was exactly sub-solar. A similar event of M 6.4
occurred south of that in Samar on May 8, 1995. These were aftershocks
of an M 7.0 which hit on April 21, 1995. One of the strongest volcanic
eruptions in the 20th century occurred in early June, 1991 at Pinatubo,
Philippines. The ash cloud from that eruption was shown to have cooled
the overall earth temperature by about 1 degree F over the next several years." (May 4, 2026)
The epicenter in Antigua is also at the third node (120 degrees) from
the M 6.7 in Honshu, Japan and may have been promoted by energy from that source as well.
O: 16MAY2026 14:50:03 17.5N 61.2W ML=6.0 NEIC ANTIGUA AND BARBUDA
The M 6.0 in Antigua and Barbuda was followed minutes later by an M 5.7 in the Solomon Islands, also
coincident with a solar flare. Further details on these event are provided
in this summary below.
A moderately strong M 5.7 occurred in the southern Solomon Islands today. NEIC reported
possible shaking up to intensity VII with observed intensities in the Solomon
Islands of III in Honiara, Guadalcanal.
This event may have been promoted by SFE associated with flare 3570 as it occurred
near the peak of that flare. Data from SWPC for this event follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3570 1508 1512 1516 C3.4 (May 16, 2026) 1.1E-03
Solomon Is. M 5.7 15:17 UT
This earthquake in the Solomon Islands is located at 140 degrees from the
M 6.0 in Antigua and occurred 27 minutes after that event. Travel time curves
show that several seismic phases from Antigua arrived in the Solomon Islands
coincident with the subsequent M 5.7 there. These included the SKS and reflected
PPPP phase. These may have helped promoted the earthquake in the Solomon
Islands as well.
O: 16MAY2026 15:17:56 8.6S 160.9E ML=5.7 NEIC SOLOMON ISLANDS
NEIC reported an earthquake of M 5.7 in the Kuril Islands was felt with intensity up to II-III in the area(s) of the Kuril Islands with likely intensity IV near Severo-Kurilsk, Russia.
O: 17MAY2026 08:04:18 50.8N 157.3E ML=5.7 NEIC KURIL ISLANDS
NEIC reported an earthquake of M 5.1 in the Admiralty Islands, Papua New Guinea was felt with intensity up to II-III in the area(s) of the Admiralty Islands, Papua New Guinea near Lorengau. This is
part of the ongoing activity related to a strong eruption of an undersea
volcano last week.
O: 17MAY2026 07:51:56 2.9S 147.8E ML=5.1 NEIC ADMIRALTY ISLANDS, P.N.G.
NEIC reported an earthquake of M 3.6 in Central California south of San Francisco was felt with intensity up to II-III in the area(s) of Central California south of San Francisco with IV in Salinas and Hollister and III in King City, San Juan Bautista, Carmel, Soledad, Modesto.
EMSC reported a good jolt near Ridgemark, California. The last earthquake
within about 50 km of this epicenter in Central California with M>=3.6
occurred half a year ago as an M 4.0 on November 27, 2025 - part of a seires
that began with an M 4.0 on November 26, 2025. At the time this summary noted:
"Moderate earthquakes also struck two areas of California today. These included
an M 4.0-4.1 and an aftershock of M 3.6-3.7 south of San Francisco and an M 4.1
in the northern Gulf of California.
NEIC reported an earthquake of M 4.0 in the area south of San Francisco, California was felt with intensity up to II-III in the area(s) of San Francisco, California with IV in Gilroy, San Juan Bautista and III in San Jose, San Francisco, Hollister, Morgan Hill, Aromas, Redwood City, San Mateo, Oakland, San Martin, Aptos, Los Altos, Fremont, Santa Clara, Los Gatos, Sausalito, Hayward, Walnut Creek, Daly City Saratoga, Stanford, Watsonville and San Francisco and Mariposa among other communities in central California.
This is the strongest earthquake within about 50 km of this epicenter since an M 4.2 on September
29, 2024. At the time this summary noted:
"A moderate earthquake of M 4.2 shook the region south of San Francisco, California today. NEIC reported it was felt with intensity IV in Salinas and King City and III in Carmel, Carmel Valley, Kerman and Fresno, California.
This follows a pair of moderate earthquakes off the coast of northern California
yesterday of M 5.1 and 4.6 as noted in the previous update to this summary:
"The strongest earthquakes in the U.S. or Canada today occurred as events of M 5.1 and M 4.6 off the coast of northern California. NEIC reported they were felt in California with intensity II at Eureka, McKinleyville, Crescent City, and in Oregon in Brookings, Gold Beach, Medfore and Grants Pass." (September 28, 2024, September 29, 2024)
Tidal stresses may have helped promote this activity as today's event in Central California
The aftershock of M 3.6 was reported by NEIC to have been felt with intensity IV in San Jose, Aptos, San Margin and III in Burlingame, San Jose, Hollister, Morgan Hill, Gilroy, Santa Clara and II in San Francisco, Los Gatos, Fremont, Sunnyvale, Mountain View, among others.
A foreshock of M 2.1 began this series near local solar midnight and may
have been promoted by the strong geomagnetic storm which commenced about
that time and/or by tidal stresses." (November 26, 2025)
Readers may note that this previous event was also associated with a strong
geomagnetic storm (as was today's).
Today's earthquake occurred near local solar midnight and was likely related to
tidal stresses with today's new moon as described in previous issues:
"The new moon will arrive on May 16, 2026 at 20:01 UT. Longitudes which are at local solar noon at this time are near 120W and those at local solar midnight near 60E. In the west these include western North America (including California, Oregon and Washington) 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." (May 14-17, 2026)
O: 17MAY2026 06:28:15 36.8N 121.4W ML=3.6 NEIC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.5 East of North Island, New Zealand was felt with intensity up to II-III in the area(s) of New Zealand near Wainui.
O: 17MAY2026 03:20:37 39.7S 178.9E ML=4.5 NEIC EAST OF NORTH ISLAND, NEW ZEALAND
NEIC reported an earthquake of M 4.4 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan in Taipei, Taichung and Hsinchu Counties, Taiwan.
EMSC reported light shaking in Taichung, Taiwan.
O: 17MAY2026 00:46:13 24.0N 121.0E ML=4.4 NEIC TAIWAN
NEIC reported an earthquake of M 2.5 in Nevada was felt with intensity up to II-III in the area(s) of Nevada at Fernley and Silver Springs.
O: 16MAY2026 18:30:31 39.2N 119.1E ML=2.5 NEIC NEVADA
NEIC reported an earthquake of M 4.4 in northern Iran was felt with intensity up to II-III in the area(s) of northern Iran near Behshahr.
EMSC reported heavy earthquake in Behshahr, Mazandaran, north of Iran.
O: 16MAY2026 16:49:18 36.9N 53.8E ML=4.4 NEIC NORTHERN IRAN
NEIC reported an earthquake of M 5.4 in Vanuatu was felt with intensity up to II-III in the area(s) of Vanuatu near Port-Vila.
O: 16MAY2026 15:58:04 17.9S 169.2E ML=5.4 NEIC SOUTHERN VANUATU
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 VI in Sadalan, V in Kornadal and III in Katnagawan, Buayan, Barra, and Panabo.
EMSC reported strong shaking in Isulan, Rotonda, Korondal City, General Santos, Mindanao, Philippines.
O: 16MAY2026 11:25:43 6.8N 124.7E ML=5.0 NEIC MINDANAO, 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 in San Diego.
O: 16MAY2026 08:28:04 33.0N 116.3W ML=2.7 NEIC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 4.6 in Coquimbo, Chile was felt with intensity up to IV in the area(s) of Coquimbo, Chile in Salamanca.
O: 17MAY2026 02:41:41 31.7S 71.5W ML=4.6 EMSC COQUIMBO, CHILE
EMSC reported an earthquake of M 4.3 in Java, Indonesia was felt with intensity up to IV in the area(s) of Java, Indonesia in Balerejo.
O: 16MAY2026 16:06:05 8.9S 111.5E ML=4.3 EMSC JAVA, INDONESIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 16, 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 when a flare occurred 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 0321 0339 0350 M1.4 (May 17, 2026) 1.4E-02 *
Guatemala M 4.0 04:03 UT
New Zealand M 4.5 03:21 UT
XXXX 0750 0756 0810 B9.2 (May 17, 2026) 9.2E-04 *
Admiralty Is. M 5.1 07:52 UT
Kuril Is. M 5.7 08:04 UT
3480 0229 0233 0235 B5.0 (May 16, 2026) 2.3E-04
Banda Sea M 4.3 02:34 UT
3560 1419 1439 1456 C1.1 (May 16, 2026) 2.2E-03
Antigua M 6.0 14:50 UT
Kyrgyzstan M 4.6 14:53 UT
3570 1508 1512 1516 C3.4 (May 16, 2026) 1.1E-03
Solomon Is. M 5.7 15:17 UT
3590 1550 1612 1622 M1.9 (May 16, 2026) 2.0E-02
Java M 4.3 16:06 UT
New Zealand M 4.4 15:48 UT
Tonga M 4.7 15:47 UT
3630 1622 1629 1634 M1.3 (May 16, 2026) 1.1E-02
Iran M 4.4 16:49 UT
3610 1739 1742 1744 M1.9 (May 16, 2026) 5.0E-03
Antofagasta M 4.4 17:59 UT
3660 1902 1907 1911 C2.5 (May 16, 2026) 1.2E-03
Washington State M 2.0 19:13 UT
3670 1957 2003 2009 C3.5 (May 16, 2026) 2.0E-03
3700 2222 2226 2230 C1.4 (May 16, 2026) 7.3E-04
3710 2313 2330 2358 C5.8 (May 16, 2026) 5.4E-03
Honshu M 4.7 00:07 UT
GEOMAGNETIC FIELD: minor storms May 17-18 unsettled May 19. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 34, high: 60, mid-latitude: 19, time of max k: 11:00 UT; Max k: 7 Global Kp 5.67 0000-0400, May 16; Sunspot Number: 83; Radio Flux: 109
May 16, 2026
Notable earthquakes and events:
A G1 to G2 class geomagnetic storm began around 11:00 UT on May 15, 2026. This
storm continued throughout the remainder of UT May 15 and intensified around 0700-1000 UT on May 16, 2026
with k of 7 at high latitudes. The Ap for the day was 35, the most disturbance
in the geomagnetic field since the Ap Index reached 75 on March 22, 2026.
The commencement of this geomagnetic storm was closely associated with the
strongest earthquake in the world in the past 25 days - an M 6.7 in Northern Honshu, Japan (see below).
An excursion in the geomagnetic field recorded by GOES-18 began about 21:15 UT.
An arcjet maneuver repositioned the satellite at 21:30 UT by 22:22 the field strength had
dropped from 150 nT at 21:20 UT to around 70 nT at 22:30. Normal operations
resumed by 22:53 UT. This excursion, like others detailed in this summary
in previous issues was associated with moderate earthquakes in Fiji at 21:15 UT.
The magnitude and number of these events is in flux ranging from M 5.7 initially
to 5.2 (EMSC) or high 4's (NEIC) later. The timing of these events suggests
similar triggering as previous such episodes (see previous issues).
This epicenter is at 104 degrees from the North Geomagnetic Pole and may
have been promoted by energy associated with that source during today's
geomagnetic storm which maximized near the time of these event and
near local solar noon in this area of Fiji.
O: 15MAY2026 21:15:25 17.8S 178.6W ML=4.7 NEIC SOUTH OF FIJI
O: 15MAY2026 22:20:25 17.8S 178.7W MB=4.5 EMSC FIJI REGION
O: 15MAY2026 21:15:25 17.8S 178.6W mb=4.7 EMSC FIJI REGION
O: 15MAY2026 21:15:26 17.8S 178.5W mb=5.2 EMSC FIJI REGION
A strong earthquake of M 6.5 (EMSC) to M 6.7 (NEIC) occurred near the east coast of Honshu, Japan on May 15
NEIC reported it was felt with intensity VII in Miyagi, IV in Akita, Iwate, Miyagi and III in Fukushima, Hkkaido, Kyoto, Tokyo, Osaka and Chiba Prefectures, Japan.
EMSC reported it was felt in Japan with strong motion at Takizawa, Kamagaya, Tokyo, Tokorozawa, and Komae.
No tsunami has been observed but slight variations in water level are expected
with this event. Intensity VII was reported from Kenennuma, Miyagi, Japan with minor damage. This is the strongest earthquake in the world since an M 7.4 about 200 km
northeast of this off Honshu, Japan on April 20, 2026. At the time this summary noted:
"A major M 7.4 earthquake occurred today off the northeast coast of Honshu, Japan.
NEIC reported intensity VII in Miyako, Iwate; VI in Hachinohe, Aomori, and Hasama, Miyagi and V in Misawa Aomori with IV in Hokkaido at Hakodate, Kitahiroshima, Namie, Fukushima, Tagajo, Miyagi, Narita, Chiba and Shiogama, Miyagi, Japan.
EMSC reported strong shaking in Japan at Aomori, Sendai, Noda, Sanriku coast, Chiba, Kamagaya, Toda, Urayasu, Tokyo, Kawasaki, Yokohama.
JMA reported the quake was felt with intensity up to VI on the Japanese Scale (out of 7)
in the areas of Hasikami, Aomori Prefecture and V in Iwate and Miyagi Prefectures. Sanriku, Iwate Prefecture. A tsunami warning has been issued by JMA
Possible tsunami waves up to 3 meters may occur in the Japanese areas of Hokkaido,
Miyagi, Fukushima and Aomori. The earthquake occurred in an area of a number of
nuclear power plants including Fukushima Daiichi and Daini in the Tokyo area
and Onagawa in Miyagi and Higashidori in Aomori Prefecture. Residents of
Japan are warned to avoid coastal areas at this time due to possible strong
currents and tidal waves. The last strong earthquake near today's epicenter
occurred as an M 6.5 on March 26. 2026. ..." (April 20, 2026)
Today's earthquake coincides with the beginning of a major
geomagnetic storm which was expected today in this summary and by SWPC. GOES 19 and GOES 18 Satellite magnetometers show a strong
increase in the geomagnetic field intensity beginning at 11:20 UT and continuing
at this writing with this sudden commencement event. It is likely the shock
wave from this helped trigger the M 6.5 in Japan. This had been anticipated
in earlier issues of this summary as:
"A moderately strong solar flare with M4.5 class energy was observed on the sun today starting about 13:00 UT.
This flare is a rim event with energy not directed towards the earth. Little
effect on earth's seismicity at this time is expected. The earth may encounter
some of the massive CME from this in the next 3-4 days and could see some
seismic jolt at that time. A coronal hole has opened up in front of the
sunspot group that generated the M-Class flare today. This will also rotate
into an earth-effective portion of the sun in the next several days.
This means strong changes in the current seismic lull are likely in the
next week with the possibility of a major earthquake with the new moon
around May 14-18. That new moon will be complete at 20:01 UT on May 16.
longitudes at local solar noon at that time will be near 120 West and at local solar midnight 60 East.
These include much of the active area of California and the western U.S.
as well as areas of Iran and Pakistan. These areas will be susceptible to
tidal triggering with this new moon." (May 11, 2026)
The new moon will arrive on May 16, 2026 at 20:01 UT. Longitudes which are at local solar noon at this time are near 120W and those at local solar midnight near 60E. In the west these include western North America (including California, Oregon and Washington) 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.
The earthquake in Japan is also closely associated with a moderately strong
solar flare which began about the same time as this earthquake. Preliminary Data on
this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3350 1107 1111 1116 B6.5 (May 15, 2026) 3.5E-04
3360 1120 1150 1154 C4.3 (May 15, 2026) 1.6E-03 *
Honshu, Japan M 6.7 11:22 UT
This epicenter is at 103 degrees from the South Geomagnetic Pole and was
probably promoted by energy associated with a strong geomagnetic and/or solar event.
O: 15MAY2026 11:22:01 38.9N 141.8E ML=6.7 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 15MAY2026 11:22:01 38.9N 141.8E ML=6.7 NEIC NEAR EAST COAST OF HONSHU, JAPAN
NEIC reported an earthquake of M 4.4 in South Island, New Zealand was felt with intensity up to II-III in the area(s) of South Island, New Zealand in Wellington.
GeoNet reported the following data for this earthquake in New Zealand:
O: 16MAY2026 06:34:14 41.7S 174.1E ML=4.4 GEONET 1235 people reported feeling this earthquake near Seddon, New Zealand with 513 at weak intensity and 554 with light shaking and 136 with moderate intensity 29 with strong, 1 with severe and 2 with extreme intensity.
This epicenter is at the sixth node (60 degrees) from the Molucca Sea and
at the fifth node (72 degrees) from Malaysia and was probably promoted by
energy from those sources.
O: 16MAY2026 06:34:13 41.8S 174.2E ML=4.4 NEIC SOUTH ISLAND, NEW ZEALAND
O: 16MAY2026 06:34:13 41.8S 174.2E ML=4.4 EMSC COOK STRAIT, NEW ZEALAND
NEIC reported an earthquake of M 3.0 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii in Kapaau, Hawi, Kamuela.
O: 15MAY2026 18:36:15 20.1N 155.9W ML=3.0 NEIC HAWAII
O: 15MAY2026 18:36:13 20.1N 155.9W ML=3.0 EMSC HAWAII REGION, HAWAII
This epicenter is at the fifth node (72 degrees) from Honshu, Japan and
may have been promoted by energy from that source.
NEIC reported an earthquake of M 3.8 in Southern Idaho was felt with intensity up to II-III in the area(s) of Southern Idaho with IV in Bern; III in Montpelier and II in Paris, Salt Lake City, Layton, Soda Springs, Lava Hot Springs, Salt Lake City.
O: 15MAY2026 11:05:45 42.3N 111.4W ML=3.8 NEIC SOUTHERN IDAHO
O: 15MAY2026 11:05:44 42.4N 111.5W MW=3.9 EMSC SOUTHERN IDAHO
EMSC reported an earthquake of M 4.9 in Southern Peru was felt with intensity up to IV in the area(s) of Southern Peru in Arica.
This earthquake occurred on the geomagnetic equator at the peak of the
geomagnetic storm today (see above). It is likely it was promoted by
strong geomagnetic effects from this storm. Total IMF reached maximum at 16nT within
minutes of this earthquake in Peru (at 15:56 UT).
This epicenter in Southern Peru is at 144 degrees from Honshu, Japan and may have been promoted
by energy from that source.
O: 16MAY2026 07:19:59 17.7S 66.8W ML=4.8 EMSC COCHABAMBA, BOLIVIA
O: 15MAY2026 15:45:18 17.7S 70.1W MB=4.9 EMSC SOUTHERN PERU
O: 15MAY2026 15:45:18 17.7S 70.1W ML=4.9 NEIC SOUTHERN PERU
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 15, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3290 0252 0309 0330 C3.3 (May 15, 2026) 5.6E-03
Costa Rica M 4.4 02:54 UT
New South Wales M 2.8 03:05 UT
3280 0148 0152 0155 C1.0 (May 15, 2026) 4.7E-04
3350 1107 1111 1116 B6.5 (May 15, 2026) 3.5E-04
Honshu, Japan M 6.7 11:22 UT
3360 1120 1150 1154 C4.3 (May 15, 2026) 1.6E-03 *
Honshu, Japan M 6.7 11:22 UT
3370 1310 1313 1317 C6.7 (May 15, 2026) 1.9E-03
3380 1340 1350 1356 C1.1 (May 15, 2026) 8.5E-04
Dominican Rep. M 3.7 13:44 UT
3410 1605 1614 1618 C9.5 (May 15, 2026) 2.9E-03
India M 3.4 16:11 UT
Sicily M 2.3 16:11 UT
3430 1732 1740 1745 B8.2 (May 15, 2026) 5.7E-04
Coquimbo M 4.2 17:38 UT
3450 1957 2006 2012 B8.8 (May 15, 2026) 6.0E-04
Chiapas M 4.3 20:14 UT
3460 2241 2250 2255 C1.0 (May 15, 2026) 6.2E-04
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms May 16-17 unsettled May 18. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 35, high: 36, mid-latitude: 22, time of max k: 14:00 UT; Max k: 6 Global Kp 6.33 2100-2400, May 15; Sunspot Number: 46; Radio Flux: 101
May 15, 2026
Notable earthquakes and events:
A strong earthquake of M 6.5 (EMSC) to M 6.7 (NEIC) occurred near the east coast of Honshu, Japan on May 15
NEIC reported it was felt with intensity VII in Miyagi, IV in Akita, Iwate, Miyagi and III in Fukushima, Hkkaido, Kyoto, Tokyo, Osaka and Chiba Prefectures, Japan.
EMSC reported it was felt in Japan with strong motion at Takizawa, Kamagaya, Tokyo, Tokorozawa, and Komae.
No tsunami has been observed but slight variations in water level are expected
with this event. Intensity VII was reported from Kenennuma, Miyagi, Japan with minor damage. This is the strongest earthquake in the world since an M 7.4 about 200 km
northeast of this off Honshu, Japan on April 20, 2026. At the time this summary noted:
"A major M 7.4 earthquake occurred today off the northeast coast of Honshu, Japan.
NEIC reported intensity VII in Miyako, Iwate; VI in Hachinohe, Aomori, and Hasama, Miyagi and V in Misawa Aomori with IV in Hokkaido at Hakodate, Kitahiroshima, Namie, Fukushima, Tagajo, Miyagi, Narita, Chiba and Shiogama, Miyagi, Japan.
EMSC reported strong shaking in Japan at Aomori, Sendai, Noda, Sanriku coast, Chiba, Kamagaya, Toda, Urayasu, Tokyo, Kawasaki, Yokohama.
JMA reported the quake was felt with intensity up to VI on the Japanese Scale (out of 7)
in the areas of Hasikami, Aomori Prefecture and V in Iwate and Miyagi Prefectures. Sanriku, Iwate Prefecture. A tsunami warning has been issued by JMA
Possible tsunami waves up to 3 meters may occur in the Japanese areas of Hokkaido,
Miyagi, Fukushima and Aomori. The earthquake occurred in an area of a number of
nuclear power plants including Fukushima Daiichi and Daini in the Tokyo area
and Onagawa in Miyagi and Higashidori in Aomori Prefecture. Residents of
Japan are warned to avoid coastal areas at this time due to possible strong
currents and tidal waves. The last strong earthquake near today's epicenter
occurred as an M 6.5 on March 26. 2026. ..." (April 20, 2026)
Today's earthquake coincides with the beginning of a major
geomagnetic storm which was expected today in this summary and by SWPC. GOES 19 and GOES 18 Satellite magnetometers show a strong
increase in the geomagnetic field intensity beginning at 11:20 UT and continuing
at this writing with this sudden commencement event. It is likely the shock
wave from this helped trigger the M 6.5 in Japan. This had been anticipated
in earlier issues of this summary as:
"A moderately strong solar flare with M4.5 class energy was observed on the sun today starting about 13:00 UT.
This flare is a rim event with energy not directed towards the earth. Little
effect on earth's seismicity at this time is expected. The earth may encounter
some of the massive CME from this in the next 3-4 days and could see some
seismic jolt at that time. A coronal hole has opened up in front of the
sunspot group that generated the M-Class flare today. This will also rotate
into an earth-effective portion of the sun in the next several days.
This means strong changes in the current seismic lull are likely in the
next week with the possibility of a major earthquake with the new moon
around May 14-18. That new moon will be complete at 20:01 UT on May 16.
longitudes at local solar noon at that time will be near 120 West and at local solar midnight 60 East.
These include much of the active area of California and the western U.S.
as well as areas of Iran and Pakistan. These areas will be susceptible to
tidal triggering with this new moon." (May 11, 2026)
The new moon will arrive on May 16, 2026 at 20:01 UT. Longitudes which are at local solar noon at this time are near 120W and those at local solar midnight near 60E. In the west these include western North America (including California, Oregon and Washington) 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.
The earthquake in Japan is also closely associated with a moderately strong
solar flare which began about the same time as this earthquake. Preliminary Data on
this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1120 1150 1220 C4.4 (May 15, 2026) 1.5E-02
Honshu Japan M 6.5 11:22 UT
This epicenter is at 103 degrees from the South Geomagnetic Pole and was
probably promoted by energy associated with a strong geomagnetic and/or solar event.
O: 15MAY2026 11:22:01 38.9N 141.8E ML=6.5 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 15MAY2026 11:22:01 38.9N 141.8E ML=6.7 NEIC NEAR EAST COAST OF HONSHU, JAPAN
A moderate solar flare of C4.4 (#3190) was followed on May 15 (UT) by a C5.1 flare (#3200).
The last day with a larger solar flare occurred on May 7, 2026 (#1710 C6.0)
and an M5.7 on May 10 (#2450) so this is a significant C-class flare.
It was in progress when the strongest earthquake since April 21, 2026
occurred as an aftershock of the M 7.4 off the coast of northeastern Honshu
Japan (April 20, 2026), thus the strongest such event in the world in
the past 25 days, a significant event. Today's earthquake was an M 6.2 in the Banda
Sea of Indonesia which occurred near local solar midnight. NEIC reported it was
felt lightly in the epicentral area and in Northern Territory, Australia with II in Darwin, Humpty Doo-MacMinns Lagoon and Howard Springs.
EMSC reported light shaking in Northern Territory, Australia at Karama.
This earthquake was likely promoted by SFE with solar flare 3190 as it occurred
near the peak output of that flare near local solar midnight.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3190 1718 1739 1821 C4.4 (May 14, 2026) 1.5E-02
Hawaii M 3.0 17:30 UT
Banda Sea M 6.2 17:53 UT
O: 14MAY2026 17:53:14 6.2S 130.4E ML=6.2 NEIC BANDA SEA
O: 14MAY2026 17:53:14 6.2S 130.4E MW=6.2 EMSC BANDA SEA
NEIC reported an earthquake of M 2.6 in Tennessee was felt with intensity up to II-III in the area(s) of Tennessee near Tiptonville.
This epicenter is at 90.0 degrees (node 4) from Honshu, Japan and was probably promoted
by energy from that source.
O: 15MAY2026 06:51:55 36.4N 89.5W ML=2.6 NEIC TENNESSEE
O: 15MAY2026 06:51:55 36.4N 89.5W MD=2.5 EMSC TENNESSEE
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 Kelseyville.
O: 15MAY2026 05:09:20 38.8N 122.8W ML=2.8 NEIC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 2.6 in Nevada was felt with intensity up to II-III in the area(s) of Nevada in Fernley.
O: 15MAY2026 03:40:34 39.4N 119.1W ML=2.6 NEIC NEVADA
O: 14MAY2026 09:22:04 39.2N 119.0W ML=2.6 EMSC NEVADA
O: 15MAY2026 03:40:34 39.4N 119.1W ML=2.6 EMSC NEVADA
NEIC reported an earthquake of M 5.4 in Papua New Guinea was felt with intensity up to II-III in the area(s) of Papua New Guinea near Lorengau.
This epicenter is at the sixth node (60 degrees) from the South Geomagnetic
Pole and at the fourth node (90 degrees) from the North Geomagnetic Pole
and was probably promoted by energy associated with those two locations.
O: 15MAY2026 01:13:58 3.0S 147.8E ML=5.4 NEIC PAPUA NEW GUINEA
O: 15MAY2026 01:13:58 3.0S 147.8E MW=5.4 EMSC ADMIRALTY ISLANDS REGION, P.N.
NEIC reported an earthquake of M 3.8 in Central Alaska was felt with intensity up to II-III in the area(s) of Central Alaska with III in Talkeetna and II in Matanuska-Sistna Borough, Girdwood and Anchorage.
O: 14MAY2026 15:50:29 62.3N 151.1W ML=3.8 NEIC CENTRAL ALASKA
O: 14MAY2026 15:50:29 62.3N 151.1W ML=3.8 EMSC CENTRAL ALASKA
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 Homer.
O: 14MAY2026 13:06:19 59.5N 152.6W ML=4.0 NEIC SOUTHERN ALASKA
NEIC reported an earthquake of M 5.3 in Colombia was felt with intensity up to II-III in the area(s) of Colombiai in Quindio at Armenia and Quimbaya and in Valle del Cauca at Cali and Ulloa and III in Pereira, Risarala, Envigado, Antioquia, Medellin, La Tebaida, Bogota and Ibague.
EMSC reported strong shaking in Colombia at Cali, Jamundi, Pereira, Dosquebradas, La Estrella, Sabaneta, Envigado, Barrio San Luis, Bogota, Barbosa and Villavicencio.
O: 14MAY2026 12:48:22 4.1N 76.7W ML=5.3 NEIC COLOMBIA
O: 14MAY2026 12:48:21 4.1N 76.6W MW=5.3 EMSC COLOMBIA
EMSC reported an earthquake of M 2.3 in Southern California was felt with intensity up to IV in the area(s) of Southern California in Aguanga with a loud noise.
O: 15MAY2026 04:12:16 33.7N 117.0W ML=2.3 ENSC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 4.4 in Costa Rica was felt with intensity up to IV in the area(s) of Costa Rica in San Ramon, Salitral, Alajuelita, and San Pedro.
A foreshock of M 4.0 was reported lightly felt in Barrio Jesus, Costa Rica.
This event occurred at the beginning of a moderate solar flare of C3.3 and
may have been promoted by SFE associated with this flare. Data for this flare
from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0252 0309 0330 C3.3 (May 15, 2026) 5.6E-03
Costa Rica M 4.4 02:54 UT
O: 15MAY2026 02:54:53 9.5N 84.6W ML=4.4 ENSC COSTA RICA
O: 14MAY2026 23:22:55 9.5N 84.6W ML=4.0 ENSC COSTA RICA
EMSC reported an earthquake of M 4.7 in Central Iran was felt with intensity up to IV in the area(s) of Central Iran in Kerman.
O: 14MAY2026 07:47:45 30.1N 56.6E ML=4.7 ENSC CENTRAL IRAN
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 14, 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 when a flare occurred 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 0252 0309 0330 C3.3 (May 15, 2026) 5.6E-03
Costa Rica M 4.4 02:54 UT
New South Wales M 2.8 03:05 UT
3040 0205 0212 0215 C1.6 (May 14, 2026) 7.5E-04
Cook Strait, N.Z. M 3.6 02:05 UT
3050 0327 0341 0349 C2.6 (May 14, 2026) 2.7E-03
Southern California M 2.3, 2.1 03:33 UT, 03:32 UT
Costa Rica M 4.4 03:46 UT
3060 0520 0537 0548 C1.9 (May 14, 2026) 2.5E-03
Oaxaca M 4.0 05:35 UT
3070 0556 0604 0608 C1.6 (May 14, 2026) 1.1E-03
3080 0631 0642 0649 C5.5 (May 14, 2026) 3.4E-03
3110 0848 0855 0858 C1.2 (May 14, 2026) 7.7E-04
3120 0909 0920 0932 C2.5 (May 14, 2026) 2.4E-03
Revilla Gigedo M 4.2 09:17 UT
3130 1046 1056 1106 C2.5 (May 14, 2026) 2.6E-03
Peru M 4.0 11:08 UT
3140 1126 1136 1145 C3.8 (May 14, 2026) 3.0E-03
Costa Rica M 3.8, 3.2 11:28 UT
3160 1424 1433 1438 C1.3 (May 14, 2026) 1.0E-03
3190 1718 1739 1821 C4.4 (May 14, 2026) 1.5E-02
Hawaii M 3.0 17:30 UT
Banda Sea M 6.2 17:53 UT
3200 1821 1840 1908 C5.1 (May 14, 2026) 1.3E-02
3240 2155 2203 2211 C1.0 (May 14, 2026) 8.9E-04
Tarapaca M 4.3 22:06 UT
South Sandwich Is. M 4.8 22:14 UT
3250 2214 2220 2228 C1.5 (May 14, 2026) 1.1E-03
South Sandwich Is. M 4.8 22:14 UT
3260 2316 2321 2326 C1.2 (May 14, 2026) 8.3E-04
Costa Rica M 4.0 23:22 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: minor storms May 16-17 major storms May 15. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 5, high: 5, mid-latitude: 5, time of max k: 00:00 UT; Max k: 3 Global Kp 2.67 0000-0200, May 14; Sunspot Number: 60; Radio Flux: 106
May 14, 2026
Notable earthquakes and events:
It was a quiet day in global seismicity. No significant earthquakes were reported.
The largest event of the day was an M 5.3 in the northern Philippines.
No major ocean storms,, solar flares or geomagnetic changes were reported
by responsible agencies. This may change tonight as the new moon approaches and solar
activity is expected to increase with minor storms tonight and major storms
tomorrow on the sun. These are likely to bring a strong earthquake near
local solar noon or midnight when associated flares occur.
NEIC reported earthquakes of M 4.4 and M 4.9 in Costa Rica were felt with intensity up to II-III in the area(s) of Costa Rica in Parrita, Jaco, Puntarenas with V and with III in Paquera, Ipis, San Rafael, Santiago and Capellades..
O: 13MAY2026 16:22:30 9.7N 84.5W MB=4.9 EMSC COSTA RICA
O: 13MAY2026 16:22:30 9.7N 84.5W MB=4.9 NEIC COSTA RICA
NEIC reported an earthquake of M 5.3 in Northern Philippines was felt with intensity up to II-III in the area(s) of Northern Philippines in Cakverua Cagayan Valley.
This epicenter is at the fifth node (72 degrees) from Tonga and may have
been promoted by energy from that source.
O: 13MAY2026 22:01:06 19.1N 121.3E MB=5.3 NEIC NORTHERN PHILIPPINES
O: 13MAY2026 22:01:06 19.1N 121.3E MW=5.3 EMSC BABUYAN ISL REGION, PHILIPPINE
O: 13MAY2026 22:10:17 19.0N 121.2E mb=4.6 EMSC BABUYAN ISL REGION, PHILIPPINES
NEIC reported an earthquake of M 3.4 in Nevada was felt with intensity up to II-III in the area(s) of Nevada in Fernley, Silver Springs, Dayton and Fallon.
O: 13MAY2026 19:38:13 39.3N 119.0W MB=3.4 NEIC NEVADA
O: 13MAY2026 19:38:12 39.3N 119.1W ML=3.4 EMSC NEVADA
O: 14MAY2026 03:24:47 39.3N 119.1W ML=2.1 EMSC NEVADA
O: 13MAY2026 13:33:04 39.3N 119.1W ML=2.6 EMSC NEVADA
O: 14MAY2026 05:25:47 39.3N 119.1W ML=2.6 EMSC NEVADA
NEIC reported an earthquake of M 4.1 off the coast of Oregon was felt with intensity up to II-III in the area(s) of Oregon at North Bend.
This epicenter is at 104 degrees from Malaysia and 101 degrees from the Molucca
Sea and may have been promoted by energy from those sources.
O: 13MAY2026 10:43:55 43.7N 127.8W MB=4.1 NEIC OFF COAST OF OREGON
O: 13MAY2026 10:43:55 43.7N 127.8W MB=4.1 EMSC OFF COAST OF OREGON
NEIC reported an earthquake of M 4.7 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan in Luchou, Taipei.
O: 13MAY2026 10:43:29 24.0N 121.7E MB=4.7 NEIC TAIWAN
O: 13MAY2026 10:43:29 24.0N 121.6E MW=4.4 EMSC TAIWAN
NEIC reported an earthquake of M 4.3 in Jamaica was felt with intensity up to II-III in the area(s) of Jamaica with IV in Saint Andrew at Gordon Town, Half Way Tree and in Easington, Saint Thomas and Mona, Kingston.
This epicenter is at 104 degrees from Tonga and at the third node (120 degrees)
from Vanuatu and may have been promoted by energy from those sources.
O: 13MAY2026 08:20:12 17.9N 76.6W MB=4.3 NEIC JAMAICA
O: 13MAY2026 08:20:14 18.0N 76.6W MB=4.3 EMSC JAMAICA REGION
EMSC reported an earthquake of M 2.3 in England was felt with light intensity up to IV in the area(s) of Colne, United Kingdom.
This epicenter is at 102 degrees from Malaysia and 144 degrees from Tonga
and may have been promoted by energy from those sources.
O: 13MAY2026 09:11:19 54.1N 2.3W MB=2.3 EMSC ENGLAND, UNITED KINGDOM
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 13, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2970 0143 0154 0201 C2.1 (May 13, 2026) 1.7E-03
Banda M 3.8 02:02 UT
2980 0631 0640 0645 C2.3 (May 13, 2026) 1.5E-03
South Sandwich Is. M 5.0 06:36 UT
2990 1028 1036 1039 C1.5 (May 13, 2026) 8.1E-04
Oregon M 4.1 10:43 UT
Taiwan M 4.4 10:43 UT
3000 1706 1714 1719 C2.0 (May 13, 2026) 1.3E-03
3010 1800 1805 1809 C1.4 (May 13, 2026) 8.0E-04
3020 1935 1948 1959 C1.4 (May 13, 2026) 1.7E-03
Peru M 4.0 19:49 UT
Honshu M 4.4 20:01 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active May 14 minor storms May 16 major storms May 15. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 10, high: 9, mid-latitude: 9, time of max k: 18:00 UT; Max k: 4 Global Kp 3.33 2000-2200, May 13; Sunspot Number: 56; Radio Flux: 103
May 13, 2026
Notable earthquakes and events:
A strong excursion occurred in the geomagnetic field as recorded by GOES-18 satellite.
This geomagnetic fluctuation began about 21:15 UT and involved a field change
of about 15% increase from 110 nT to 130 nT over the next two minutes. The satellite position was
corected by an arcjet orbital correction and normal operations resumed by 22:36.
It was not observed in the GOES-19 satellite magnetometer. The strongest
earthquake in the world today - an M 5.7 south of Fiji occurred within a minute
of the start of this geomagnetic excursion at 21:20 UT on May 12, 2026.
This was the strongest earthquake in the world since an M 5.8-6.1 in the Rat
Islands on May 9, 2026. This pattern was described in this summary in the previous issue and has
been persistent with these arcjet corrected satellite geomagnetic fluctuations.
In the past summary this was noted with the last such occurrence of such
a geomagnetic excursion as:
"A strong excursion occurred in the geomagnetic field as recorded by GOES-19 satellite.
This summary has noted these excursions on many previous occasions and at
least five times in the past week. They look like an Electromagnetic Pulse
(EMP) on the magnetometer. In each of the lastest instances, a significant
earthquake occurred within a minute of the excursion somewhere in the world.
This is well beyond random but a causal mechanism is elusive. Today's event
involved a 50% increase in the field strength within a minute of 05:35 UT
on May 11. An arcjet maneuver was performed at the satellite to stabilize
the orbit and normal functions resumed about 07:20 UT. This excursion was not
reflected in readings from the GOES-18 magnetomenter and so may not
reflect a real change in the overall geomagnetic field but a local variation
at the GOES-19 satellite. The GOES-19 satellite is in a stationary orbit at 72.5
West longitude so it may be of some significance that a moderate earthquake
of M 4.6 in Antofagasta, Chile at 05:35 UT was simultaneous with this
geomagnetic anomaly. This is the strongest earthquake in South of North America
in the past 24 hours, so it is a significant regional event." (May 11-12, 2026)
Prior to that the last such geomagnetic excursion occurred on May 4 and coincided
with the last earthquake in the world of M>=6 - an M 6.0 in Samar, Philippines. At the
time this summary noted:
"A strong variation in geomagnetic field strength occurred as recorded on the GOES-18
magnetometer at 06:10 UT today. This required a orbital arcjet correction
at the same time. This geomagnetic field excursion occurred at the
same time as the M 6.0 in the area of Samar, Philippines (at 06:10 UT)." (May 4, 2026)
Similarly on May 1, 2026 a geomagnetic excursion accompanied an M 5.2 in Nevada
as described in this summary at the time:
"A moderate earthquake of M 5.2 today continued a series of moderate to strong
earthquakes in western Nevada. The M 4.9-5.2 was associated with a group of
...
Today's earthquake was within a couple of minutes of local solar midnight when
this geomagnetic effect peaked near 07:56 UT (00:00 UT local solar time) on GOES 19 Magnetometer
when an arcjet stabilizing maneuver corrected the satellite position." (May
The M 5.7 in the area of Tonga and Fiji today was reported by NEIC to have probably
been felt with intensity up to III in the area southwest of Houma, Tonga.
The last earthquake within about 200 km of this epicenter in Fiji with M>=5.7
occurred on May 25, 2025 with M 6.0.
The epicenter is at the fifth node (72 degrees) from Malaysia and Honshu, Japan
and at the sixth node (60 degrees) from the Molucca Sea and at the seventh
node (51.3 degrees) from the South Geomagnetic Pole and may have been promoted
by energy from those sources.
O: 12MAY2026 21:19:36 23.2S 176.8W MB=5.7 NEIC SOUTH OF FIJI
O: 12MAY2026 21:19:36 23.3S 176.8W MW=5.7 EMSC SOUTH OF FIJI ISLANDS
Like the M 5.8 in the Rat Islands on May 9 whose s-wave apparently triggered
a M 4.9 off the coast of Northern California 15-16 minutes later today's
event in Fiji also appears to have triggered an unusual event in California.
This event may have been felt lightly in Rosarito, Mexico according to data from EMSC.
This was an M 3.2 in the northern Gulf of California 21 minutes and 35 seconds
and 80 degrees from the Fiji event. Travel time tables show the S-wave
arriving in the epicenter in the Gulf of California 21 minutes and 8 seconds
after the event in Fiji. Adjustment for depth places this wave as a trigger
for the event in The Gulf of California. While not a strong earthquake (M 3.2), the
epicenter in the Gulf of California is unusual and occurs near the initiation
of the San Andreas Fault zone to the north. The last earthquake within about
50 km of this epicenter in the Gulf of Caifornia with equal or greater
magnitude was an M 3.6 on February 21, 2025. The last of M>4 was an M 4.3-4.6 on July 16, 2023.
At the time this summary noted:
"A strong swarm of earthquakes also occurred today in Baja and the Gulf of
California, Mexico. The strongest earthquakes in this series occurred within
minutes of local solar noon with M 4.6 and 4.3 but the series began with smaller
event including an M 4.0 shortly after the M 7.2 in the Alaska Peninsula.
NEIC reported the earthquake of M 4.6 in the Gulf of California, Mexico was felt with intensity II-III in the area(s) of Sonora, Mexico in Puerto Penasco (VI) and Sonoita; in San Felipe, Baja California and in Arizona at Somerton (IV), Wellton, and Sells.
Several moderate earthquakes including an M 4.2 were also felt in Baja California today. These were felt lightly in Baja California at Tijuana.
This activity was probably triggered by strong tidal stresses with the
new moon of July 17." (July 16, 2023)
This earthquake in the Gulf of California was followed by an M 3.3 48 minutes
after Fiji with the arrival of an S-phase from that source. These events
follow the strong swarm of earthquakes about 150 km to the northwest in the
Brawley are of Southern California and are likely important stress indicators
following that swarm. More of these types of events are likely in the next
several days.
This activity in the Gulf of California may also have been promoted by
SFE from solar flare 2950 which began at the time of the M 3.2 in the
Gulf of California. Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2950 2142 2148 2151 C1.1 (May 12, 2026) 5.7E-04
Gulf of California M 3.2 21:41 UT
Tonga M 5.1 21:53 UT
O: 12MAY2026 21:41:21 31.6N 114.5W MB=3.2 NEIC GULF OF CALIFORNIA
O: 12MAY2026 21:41:21 31.6N 114.5W ML=3.2 EMSC GULF OF CALIFORNIA
O: 12MAY2026 22:07:17 31.6N 114.6W ML=3.3 EMSC GULF OF CALIFORNIA
O: 12MAY2026 22:07:17 31.6N 114.6W MB=3.3 NEIC GULF OF CALIFORNIA
O: 12MAY2026 21:13:17 31.0N 115.8W MB=3.6 NEIC BAJA CALIFORNIA
O: 12MAY2026 21:13:17 31.0N 115.8W ML=3.6 EMSC BAJA CALIFORNIA, MEXICO
O: 12MAY2026 21:21:16 30.9N 115.9W ML=3.4 EMSC BAJA CALIFORNIA, MEXICO
O: 12MAY2026 21:21:16 30.9N 115.9W MB=3.4 NEIC BAJA CALIFORNIA
An M 4.3-4.5 earthquake was widely felt in the area of Tehran, Iran today. NEIC
reported it was felt with IV in Tehran; III in Qods and II in Eslam Shahr, Teheran.
EMSC reported strong shaking in Iran at Damavand, Tajrish, Tehran, Shahr-e Qods, Karaj. Shahrak.
Some have suggested that this event was an explosive test. This seems unlikely
due to it magnitude, timing and location. The event occurred within minutes
of local solar midnight with a magnitude much greater than could be achieved
with a conventional test explosion. This area of Iran is subject to major
earthquakes including deadly and extremely damaging events on September 1, 1962 (M 7.3);
July 2, 1957 (M 7.4) and July 9, 1895 (M 8.2). The interval between major
events of this type in the area appears to be about 62-65 years. Since the
last such event was the M 7.3 on September 1, 1962, the next could be expected
soon. Today's event could be a foreshock to such an earthquake.
O: 12MAY2026 20:16:09 35.7N 52.1E MB=4.3 NEIC NORTHERN IRAN
O: 12MAY2026 20:16:13 35.8N 51.9E MB=4.3 EMSC NORTHERN IRAN
NEIC reported an earthquake of M 4.5 in Nicaragua was felt with intensity up to II-III in the area(s) of Nicaragua in Ciudad Sandino, Managua.
EMSC reported moderate intensity in Nicaragua at Ciudad Sandino, El Crucero, Managua, Nagarote.
This epicenter is at 144 degrees from the Molucca Sea and may have been
promoted by energy from that source.
O: 13MAY2026 03:45:21 11.5N 86.7W MB=4.5 NEIC NICARAGUA
O: 13MAY2026 03:45:21 11.7N 86.7W MB=4.5 EMSC NEAR COAST OF NICARAGUA
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 with III in Ramona, Valley Center and II in Escondido, Descanso, Warner Springs, Poway, and Menifee.
This event occurred near local solar noon and was floowed by a series of events to the
southeast of M 3.4 and 3.6 in Baja, California and M 3.2 in the Gulf of California
in the next several minutes. This is not part of the series of events near Brawley two days ago as it occurred
about 50 km northwest of that on the San Andreas. It may represent a potentially
dangerous migration of stress along the fault to the northwest, however, so
the area should be continually monitored at this time.
O: 12MAY2026 20:55:58 33.2N 116.8W MB=2.7 NEIC SOUTHERN CALIFORNIA
O: 12MAY2026 20:55:58 33.2N 116.8W ML=2.7 EMSC SOUTHERN CALIFORNIA
O: 12MAY2026 10:19:19 33.5N 116.7W ML=2.2 EMSC SOUTHERN CALIFORNIA
O: 12MAY2026 16:46:47 33.4N 116.3W ML=2.1 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.0 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Middletown, Kelseyville and Hidden Valley Lake.
O: 12MAY2026 19:38:13 38.8N 122.6W MB=3.0 NEIC NORTHERN CALIFORNIA
O: 12MAY2026 19:38:13 38.8N 122.6W ML=2.9 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 5.6 in the Solomon Islands was felt with intensity up to II-III in the area(s) of the Solomon Islands near Lata.
This epicenter is at the seventh node (51.4 degrees) from Malaysia and may have
been promoted by energy from that source.
O: 12MAY2026 15:39:30 10.6S 164.9E MW=5.6 NEIC SOLOMON ISLANDS
O: 12MAY2026 15:39:28 10.5S 165.0E MW=5.6 EMSC SANTA CRUZ ISLANDS REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 12, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2790 0048 0101 0132 C1.3 (May 12, 2026) 3.2E-03
2840 0644 0654 0704 C1.0 (May 12, 2026) 1.3E-03
Taiwan M 5.1 06:53 UT
2850 0926 0935 0943 C1.1 (May 12, 2026) 1.0E-03
2860 1038 1049 1100 C1.4 (May 12, 2026) 1.9E-03
Antofagasta M 4.4 10:40 UT
2900 1240 1249 1252 C2.0 (May 12, 2026) 1.0E-03
North Is. New Zealand M 4.2 12:42 UT
Argentina M 4.5 12:50 UT
2910 1453 1458 1500 C1.3 (May 12, 2026) 5.1E-04
Sichuan China M 4.5 14:55 UT
Santa Cruz Is. M 5.6 15:39 UT
2920 1711 1717 1719 C1.5 (May 12, 2026) 6.5E-04
2950 2142 2148 2151 C1.1 (May 12, 2026) 5.7E-04
Gulf of California M 3.2 21:41 UT
Tonga M 5.1 21:53 UT
2960 2211 2217 2223 C1.0 (May 12, 2026) 7.5E-04
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 14 minor storms May 15 active May 13. Solar M-flare chance: 40% X-class: 10% proton storm: 10%
AP Indicies: global: 4, high: 2, mid-latitude: 2, time of max k: 15:00 UT; Max k: 1 Global Kp 1.00 1500-2400, May 12; Sunspot Number: 58; Radio Flux: 111
May 12, 2026
Notable earthquakes and events:
A strong excursion occurred in the geomagnetic field as recorded by GOES-19 satellite.
This summary has noted these excursions on many previous occasions and at
least five times in the past week. They look like an Electromagnetic Pulse
(EMP) on the magnetometer. In each of the lastest instances, a significant
earthquake occurred within a minute of the excursion somewhere in the world.
This is well beyond random but a causal mechanism is elusive. Today's event
involved a 50% increase in the field strength within a minute of 05:35 UT
on May 11. An arcjet maneuver was performed at the satellite to stabilize
the orbit and normal functions resumed about 07:20 UT. This excursion was not
reflected in readings from the GOES-18 magnetomenter and so may not
reflect a real change in the overall geomagnetic field but a local variation
at the GOES-19 satellite. The GOES-19 satellite is in a stationary orbit at 72.5
West longitude so it may be of some significance that a moderate earthquake
of M 4.6 in Antofagasta, Chile at 05:35 UT was simultaneous with this
geomagnetic anomaly. This is the strongest earthquake in South of North America
in the past 24 hours, so it is a significant regional event. EMSC gives the following parameters for this Chilean
earthquake which NEIC reported was felt near San Pedro de Atacama, Chile with
light intensity:
O: 11MAY2026 05:35:51 23.0S 68.6W MB=4.6 NEIC ANTOFAGASTA, CHILE
O: 11MAY2026 05:35:51 23.0S 68.6W MB=4.6 EMSC ANTOFAGASTA, CHILE
Otherwise, it was a quiet day in global seismicity. The largest earthquakes
in the world was an M 5.1 in Taiwan and an M 5.2 in the Soloomon Islands.
Both were lightly felt but no damage occurred. The swarm in southern California
has ceased for the moment but may return later in the week. The geomagnetic
field was quiet, there were no solar flares of C2 or greater energy and there were no tropical cyclones active today.
NEIC reported an earthquake of M 4.3 in Cook Strait, New Zealand may have been felt in thie area of Owhiro Bay.
GeoNet reported the following data for this event in New Zealand.
O: 12MAY2026 09:02:57 41.4S 174.5E ML=4.2 GEONET 5993 people reported feeling this earthquake near Seddon, New Zealand with 3513 at weak intensity and 2298 with light shaking and 171 with moderate intensity 5 with strong, 1 with severe and 5 with extreme intensity.
This epicenter is at the sixth node (60 degrees) from the Molucca Sea and at the fifth node
(72 degrees) from Malaysia and may have been promoted by energy from those
sources.
O: 12MAY2026 09:02:57 41.5S 174.6E MB=4.3 NEIC OWHIRO BAY, NEW ZEALAND
NEIC reported an earthquake of M 5.1 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan in Yunlin, Taipei and Hsinchu Counties.
EMSC reported jolt was felt in Taichung.
This epicenter is at the sixth node (60 degrees) from the Vanuatu and at the fifth node
(72 degrees) from Tonga and may have been promoted by energy from those
sources.
O: 12MAY2026 06:53:32 23.3N 121.5E MB=5.1 NEIC TAIWAN
O: 12MAY2026 06:53:32 23.2N 121.5E MW=5.1 EMSC TAIWAN
NEIC reported an earthquake of M 4.3 in Southeastern Honshu, Japan was felt with intensity up to II-III in the area(s) of Honshu in Tochigi, Ibaraki, Chiba, Kangawa and Tokyo Prefectures.
EMSC reported noise with felt activity in Japan at Kamagaya, Wako, Tokyo, Urayasu and Machida.
O: 12MAY2026 00:02:38 36.3N 139.7E MB=4.3 NEIC HONSHU, JAPAN
O: 12MAY2026 00:02:37 36.2N 139.8E MW=4.3 EMSC EASTERN HONSHU, JAPAN
NEIC reported an earthquake of M 2.8 in Southern Nebraska was felt with intensity up to II-III in the area(s) of Southern Nebraska in Omaha.
O: 11MAY2026 14:40:16 40.2N 98.4W MB=2.8 NEIC NEBRASKA
O: 11MAY2026 14:40:16 40.2N 98.4W ML=2.8 EMSC NEBRASKA
NEIC reported earthquakes of M 3.2 and M 2.9 in Northern California were felt with intensity up to II-III in the area(s) of Northern California at Eureka.
This epicenter is at 104 degrees from the Molucca Sea and may have been
promoted by energy from that source.
O: 11MAY2026 11:16:04 39.9N 123.7W MB=3.2 NEIC NORTHERN CALIFORNIA
O: 11MAY2026 11:04:23 39.9N 123.7W MB=2.9 NEIC NORTHERN CALIFORNIA
O: 11MAY2026 08:40:15 39.9N 123.7W MD=2.6 EMSC NORTHERN CALIFORNIA
O: 11MAY2026 08:19:58 39.9N 123.7W MD=2.7 EMSC NORTHERN CALIFORNIA
O: 11MAY2026 11:16:04 39.9N 123.7W ML=3.0 EMSC NORTHERN CALIFORNIA
O: 11MAY2026 16:24:46 39.9N 123.7W MD=2.7 EMSC NORTHERN CALIFORNIA
O: 11MAY2026 23:12:04 39.9N 123.7W MD=2.4 EMSC NORTHERN CALIFORNIA
O: 11MAY2026 11:04:23 40.0N 123.7W MD=2.7 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 5.2 in the Solomon Islands was felt with intensity up to II-III in the area(s) of the Solomon Islands in Honiara, Guadacanal.
This epicenter is at the seventh node (51.4 degrees) from Honshu, Japan and at the
eighth node (45 degrees) from Malaysia and may have been promoted by energy
from those sources.
O: 11MAY2026 09:48:51 9.3S 159.2E MB=5.2 NEIC SOLOMON ISLANDS
O: 11MAY2026 09:48:53 9.3S 159.2E MW=5.2 EMSC SOLOMON ISLANDS
EMSC reported an earthquake of M 4.5 in Antofagasta, Chile was felt with intensity up to IV in the area(s) of Antofagasta, Chile in Copiapo.
O: 11MAY2026 23:16:36 25.6S 71.3W MB=4.5 EMSC OFF COAST OF ANTOFAGASTA, CHILE
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2580 0045 0052 0058 C1.0 (May 11, 2026) 7.9E-04
2640 0821 0832 0841 C1.4 (May 11, 2026) 1.4E-03
2670 1149 1154 1159 C1.2 (May 11, 2026) 7.2E-04
2720 1405 1415 1417 C1.8 (May 11, 2026) 9.8E-04
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 14 active May 12-13. Solar M-flare chance: 45% X-class: 10% proton storm: 10%
AP Indicies: global: 5, high: 4, mid-latitude: 4, time of max k: 00:00 UT; Max k: 2 Global Kp 2.00 0000-0300, May 11; Sunspot Number: 79; Radio Flux: 116
May 11, 2026
Notable earthquakes and events:
A strong excursion occurred in the geomagnetic field as recorded by GOES-19 satellite.
This involved a 50% increase in the field strength within a minute of 05:35 UT
on May 11. An arcjet maneuver was performed at the satellite to stabilize
the orbit and normal functions resumed about 07:20 UT. This excursion was not
reflected in readings from the GOES-18 magnetomenter and so may not
reflect a real change in the overall geomagnetic field but a local variation
at the GOES-19 satellite. The GOES-19 satellite is in a stationary orbit at 72.5
West longitude so it may be of some significance that a moderate earthquake
of M 4.6 in Antofagasta, Chile at 05:35 UT was simultaneous with this
geomagnetic anomaly. This is the strongest earthquake in South of North America
in the past 24 hours, so it is a significant regional event. EMSC gives the following parameters for this Chilean
earthquake which NEIC reported was felt near San Pedro de Atacama, Chile with
light intensity:
O: 11MAY2026 05:35:51 23.0S 68.6W MB=4.6 NEIC ANTOFAGASTA, CHILE
O: 11MAY2026 05:35:51 23.0S 68.6W MB=4.6 EMSC ANTOFAGASTA, CHILE
A moderately strong solar flare with M4.5 class energy was observed on the sun today starting about 13:00 UT.
This flare is a rim event with energy not directed towards the earth. Little
effect on earth's seismicity at this time is expected. The earth may encounter
some of the massive CME from this in the next 3-4 days and could see some
seismic jolt at that time. A coronal hole has opened up in front of the
sunspot group that generated the M-Class flare today. This will also rotate
into an earth-effective portion of the sun in the next several days.
This means strong changes in the current seismic lull are likely in the
next week with the possibility of a major earthquake with the new moon
around May 14-18. That new moon will be complete at 20:01 UT on May 16.
longitudes at local solar noon at that time will be near 120 West and at local solar midnight 60 East.
These include much of the active area of California and the western U.S.
as well as areas of Iran and Pakistan. These areas will be susceptible to
tidal triggering with this new moon.
The M 5.0 earthquake off the coast of northern California yesterday (see previous issue)
occurred near the northern terminus of the San Andreas Fault in California.
It was followed by an M 4.7 and a number of other moderate and light earthquakes
in Southern California near Brawley near the southern terminus of the
San Andreas Fault. This suggests a connection between these two events
through the San Andreas Fault system. The earthquake off northern California
was apparently triggered by seismic waves from the M 5.8 earthquake in
the Rat Islands 15-16 minutes earlier (see previous analysis in this
summary. This suggest the entire system of faults is near rupture and
that a strong earthquake on this system is near. An M 2.7 following the M4+ solar flare (see above) near local
noon today in San Francisco, California may indicate one of the areas
where stress is high and a moderate quake could occur under the right
environmental conditions. Over the past months a consistent pattern of
light to moderate earthquakes in this area near local solar noon or midnight
has suggested triggering from tidal and/or geomagnetic environmental effects.
As noted in the previous summary, the M 5.0 off northern California occurred as several seismic
waves were passing through the are which originated with an M 5.8 in the Rat
Islands, Alaska. The triggering relation between these events was strengthened
when an M 4.4 aftershock in the Rat Islands occurred today was the S-phase
from Southern California was in the area of the epicenter in the Rat Islands
slightly more than 17 minutes later. Aftershocks continued today in the Brawley area of Southern California. Some
of these were lightly felt. In the previous issue of this summary this
swarm had been addressed as:
"A moderate earthquake of M 4.7 near Brawley, Southern California joined a number of light foreshocks
and aftershocks today in the area. NEIC reported the mainshock which occurred
local solar midnight may have caused slight damage with intensity VI in Brawley, California
with IV in Holtville, Imperial, Calipatria, Vista and III in San Diego, El Cajon, El Centro and La Mesa and in Cibola, Arizona.
Other moderate quakes in the series included events of M 4.5 and M 4.0 as foreshocks of the M 4.7.
Earthquakes in this area are often associated with swarms with larger earthquakes
in the middle of the sequence so additional activity in this swarm is expected
today and tomorrow.
This is an area which had been expected to see enhanced seismicity at this time as noted in the previous issue
of this summary.
"An M 3.1 in Baja and Southern California at 22:13 UT also occurred
and may indicated instability in that area leading to enhanced seismicity
in the next day or so." (May 8-9, 2026)
The last earthquake within about 100 km of this epicenter in Southern California
with M>=4.7 occurred as an M 4.9 on May 12, 2024 although an M 5.2 did occur
about 100 km west of this on April 14, 2025. At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 4.9-5.0 in Baja California
near the border with California (US), It was widely felt with intensity up to
VI in the region of Delta, Baja California, Mexico. EMSC reported light to moderate
shaking in Southern California in Calexico, El Centro, Carlsbad, Oceanside, in Arizona at Yuma; Holtville and in Baja California in Mexicali.
Numerous foreshocks and aftershocks were felt in the Delta Baja California region of Mexico with light to moderate intensity (II-IV).
The M 4.9 is the strongest earthquake in Baja within about 200 km of this event in more than three years.
An M 4.8 hit the same epicenter on March 31, 2021. The series began with a
light event of M 2.4 that occurred at the height of the strongest solar flare
of the day - an X1.0 which peaked at 16:35 UT. An earthquake of M 3.9 off the
coast of Honshu, Japan also occurred with the peak of this X1.0 class flare
at 16:37 UT. A similar simultaneity of the foreshock to this event occurred
with M 4.1 on May 8, 2024 and an X-class solar flare. At the time this summary noted
this as:
"The strongest earthquake in the U.S. or Canada today was an M 4.1 on the
border between Southern California and Baja California. This earthquake
was closely associated with a series of strong solar flares beginning
with flare 270 (C9.3) around 01:00 UT and ending with flares 280 and 290 (about 01:15-01:35 UT) - an X1.0 class flare.
It is likely it was promoted by SFE from those sources. (May 8, 2024)
This swarm in Baja California began at the end of flare 2400 - the largest
of the day and was probably precipitated by SFE from that flare. ..." (April 14, 2025) SWPC
The last event with significantly larger magnitude within the area of today's
swarm was an M 5.3 on June 5, 2021.
Forecasts 181793 had expected an event within about 10-25 km of this epicenter with magnitude
up to M 4.8 was possible around May 3 or May 9, 2026.
P: 03MAY2026 181793 32.9N 115.6W 2.5-4.8 CAAAA So. California
P: 09MAY2026 181793 32.8N 116.0W 2.5-4.6 AAAAA So. California
P: 12MAY2026 182102 33.0N 115.9W 2.5-4.5 AAAAA So. California
P: 13MAY2026 182100 32.9N 115.6W 2.5-5.5 AAAAA So. California
Following is a listing of events of M>=3 in this sequence since the previous summary. A more extensive
listing of events of M>=2 can be found in the "Data" section of this summary.
O: 10MAY2026 07:10:24 33.0N 115.6W Mw=4.7 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:14:38 33.0N 115.6W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:15:37 33.0N 115.6W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:27:51 33.0N 115.6W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:41:25 33.0N 115.6W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 03:39:29 32.9N 115.6W MB=4.5 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 03:13:23 32.9N 115.6W MB=4.0 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 14:16:45 32.9N 115.6W MB=2.7 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 10:47:25 32.9N 115.6W MB=3.0 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 5.1 in Fiji was felt not felt in this remote area.
This is the strongest earthquake in the world today. It occurred within minutes
This is the strongest earthquake in the world today. It occurred within minutes
of local solar noon and was probably promoted by tidal and/or geomagnetic
stresses which maximize near this hour.
This activity in Fiji may have been promoted by SFE from solar flare 2560
as it occurred at the peak output of that flare near local solar noon when
such effects are maximized. Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2560 2311 2318 2323 C1.3 (May 10, 2026) 8.5E-04
Fiji M 5.1 23:16 UT, M 5.0 23:21 UT
This epicenter is at the fifth node (72 degrees) from Honshu, Japan
and may have been promoted by energy from that source.
O: 10MAY2026 23:15:43 23.4S 179.9W ML=5.1 NEIC SOUTH OF FIJI ISLANDS
O: 10MAY2026 23:15:41 23.5S 179.9W MB=5.1 EMSC SOUTH OF FIJI ISLANDS
O: 10MAY2026 23:20:54 23.4S 179.8W mb=5.0 EMSC SOUTH OF FIJI ISLANDS
O: 10MAY2026 23:20:55 23.5S 179.8W ML=5.0 NEIC SOUTH OF FIJI ISLANDS
NEIC reported an earthquake of M 2.7 in San Francisco, California was felt with intensity up to II-III in the area(s) of San Francisco, California with intensity III in Richmond, Crockett, Hercules, Berkeley, El Sobrante, and II in Pinole, Martinez, Benicia and El Cerrito.
EMSC reported it was felt as a sudden jolt in California at El Sobrante, Rodeo, Kensington.
This earthquake occurred near local noon and may have been promoted by
the M4+ solar flare several hours earlier and/or other geomagnetic stresses
which maximize near this hour.
Like the activity in the Fiji Islands today (see above) this epicenter is at the fifth node (72 degrees) from Honshu, Japan
and may have been promoted by energy from that source.
O: 10MAY2026 22:55:52 38.0N 122.3W ML=2.7 NEIC SAN FRANCISCO, CALIFORNIA
O: 10MAY2026 22:55:52 38.0N 122.3W MD=2.7 EMSC SAN FRANCISCO BAY AREA, CALIF.
NEIC reported an earthquake of M 4.1 in Queen Charlotte Island, Canada was not reported felt by NEIC.
O: 10MAY2026 22:45:17 53.0N 132.7W ML=4.1 NEIC QUEEN CHARLOTTE IS. CANADA
O: 10MAY2026 22:45:17 53.0N 132.7W ML=4.0 EMSC HAIDA GWAII REGION
NEIC reported an earthquake of M 4.6 in northern Mariana Islands was felt with intensity up to II-III in the area(s) of northern Mariana Islands in Tinian.
O: 10MAY2026 21:08:18 17.9N 145.7E ML=4.6 NEIC SAIPAN, MARIANA ISLANDS
O: 10MAY2026 21:08:14 17.9N 145.8E MB=4.6 EMSC ALAMAGAN REG, N. MARIANA ISLAN
NEIC reported an earthquake of M 4.1 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska at Anchor Point, Homer and Kodiak.
O: 10MAY2026 18:59:49 59.7N 152.4W ML=4.1 NEIC SOUTHERN ALASKA
O: 10MAY2026 18:59:50 59.8N 152.5W MW=4.3 EMSC SOUTHERN ALASKA
NEIC reported an earthquake of M 4.1 in Nevada was felt with intensity up to II-III in the area(s) of Nevada in Silver Springs, Fernley, Fallon, Dayton, Gardnerville, Reno.
Like the activity in the Fiji Islands and San Francisco today (see above) this epicenter is at the fifth node (72 degrees) from Honshu, Japan
and may have been promoted by energy from that source.
O: 10MAY2026 18:22:13 39.3N 119.1W ML=4.1 NEIC NEVADA
O: 10MAY2026 18:22:13 39.3N 119.1W MW=4.0 EMSC NEVADA
O: 10MAY2026 18:24:33 39.3N 119.1W ML=2.8 EMSC NEVADA
O: 10MAY2026 18:43:42 39.3N 119.1W ML=2.2 EMSC NEVADA
O: 10MAY2026 19:08:07 39.3N 119.1W ML=2.0 EMSC NEVADA
O: 10MAY2026 19:12:50 39.3N 119.1W ML=2.0 EMSC NEVADA
O: 10MAY2026 19:25:16 39.3N 119.1W ML=2.1 EMSC NEVADA
O: 10MAY2026 21:25:54 39.3N 119.1W ML=2.2 EMSC NEVADA
O: 11MAY2026 00:03:28 39.3N 119.1W ML=2.0 EMSC NEVADA
O: 11MAY2026 01:11:31 39.3N 119.1W ML=2.1 EMSC NEVADA
NEIC reported an earthquake of M 5.2 in Papua New Guinea was felt with intensity up to II-III in the area(s) of Papua New Guinea at Madang, Kainantu, Mount Hagen and Goroka.
This epicenter is at the eighth node (45 degrees) from Honshu, Japan
and may have been promoted by energy from that sources.
O: 10MAY2026 16:34:33 5.3S 145.5E ML=5.2 NEIC PAPUA NEW GUINEA
O: 10MAY2026 16:34:33 5.3S 145.6E MW=5.3 EMSC EASTERN NEW GUINEA REG., P.N.G
The M 5.3-5.5 in Bio-Bio, Chile early on May 10, 2026 (see previous issue for
discussion) was apparently promoted by a C1.6 solar flare (#2260).
It occurred at the peak output of that flare. Data for this flare from
SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2260 0227 0233 0236 C1.6 (May 10, 2026) 1.2E-03
Bio-Bio, Chile M 5.3 02:34 UT
EMSC reported an earthquake of M 4.6 in Dodecanese Islands, Greece was felt with intensity up to IV in the area(s) of Dodecanese Islands, Greece in Gournes, Kokkini Chani, and in Turkey at Yalikavak, Oren and Fethiye.
O: 10MAY2026 20:29:55 36.7N 26.8E ML=4.6 EMSC DODECANESE ISLANDS, GREECE
EMSC reported an earthquake of M 4.6 in Azores Islands was felt with intensity up to IV in the area(s) of Azores Islands in Angra do Heroismo, Feteira, Cais do Pico, Praia da Vitoria and Rosto de Cao.
This epicenter is at 102 degrees from Honshu, Japan and may have been promoted
by energy from that source.
O: 10MAY2026 12:21:22 38.4N 27.7W ML=4.6 EMSC AZORES ISLANDS, PORTUGAL
GeoNet reported the following data for an M 4.0 in South Island, New Zealand today:
O: 10MAY2026 11:04:51 41.4S 172.9E ML=4.0 GEONET 151 people reported feeling this earthquake near Seddon, New Zealand with 98 at weak intensity and 53 with light shaking and 0 with moderate intensity 0 with strong, 0 with severe and 0 with extreme intensity.
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-11 00:00 UT 10.3N 131.0E 35 kts North Pacific
Tropical Storm Hagupit continued today in north Pacific area with winds up to 35 kts west of Guam. This storm is expected to dissipate in the next day and not to threaten Islands in the northwest Pacific at this time. No sigificant seismicity is likely to be promoted with this storm. The antipode is at 10S 48W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2260 0227 0233 0236 C1.6 (May 10, 2026) 1.2E-03
Bio-Bio, Chile M 5.3 02:34 UT
Southern California various 02:27-02:42 UT
2360 0236 0240 0242 C2.0 (May 10, 2026) 8.5E-04
Southern California various 02:27-02:42 UT
Tanimbar M 5.0 02:42 UT
2270 0356 0403 0408 C1.4 (May 10, 2026) 1.0E-03
Southern California M 2.4, 2.3 03:59 UT
2320 0459 0504 0510 C2.0 (May 10, 2026) 1.1E-03
Southern California M 2.4, 2.1 05:03 UT
Papua M 3.9 04:59 UT
2370 0632 0640 0646 C1.4 (May 10, 2026) 1.0E-03
Southern California M 3.0, 3.2, ... 06:36-06:44 UT M 4.7 07:10 UT
Hindu Kush, M 4.1 06:36 UT
2390 0728 0734 0738 C2.0 (May 10, 2026) 1.1E-03
Southern California M 3.2 07:28 UT
Rat Islands M 4.4 07:28 UT
2410 0915 0924 0928 C1.9 (May 10, 2026) 1.1E-03
2420 0932 0939 0942 C3.7 (May 10, 2026) 1.6E-03
2430 1036 1043 1047 C1.1 (May 10, 2026) 7.2E-04
Los Angeles CA. M 2.2 10:34 UT
2450 1319 1339 1402 M5.7 (May 10, 2026) 8.5E-02
Cenral Peru M 4.2 13:51 UT
2520 1927 1934 1943 C1.2 (May 10, 2026) 1.1E-03
Myanmar M 5.0 19:36 UT
2550 2058 2109 2120 C1.3 (May 10, 2026) 1.6E-03
Kuril Is. M 4.2 21:00 UT
Mariana Is. M 4.6 21:08 UT
2560 2311 2318 2323 C1.3 (May 10, 2026) 8.5E-04
Fiji M 5.1 23:16 UT, M 5.0 23:21 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 11 and 13 quiet May 12. Solar M-flare chance: 45% X-class: 20% proton storm: 20%
AP Indicies: global: 5, high: 4, mid-latitude: 4, time of max k: 12:00 UT; Max k: 3 Global Kp 1.67 2000-2300, May 10; Sunspot Number: 89; Radio Flux: 126
May 10, 2026
Notable earthquakes and events:
A moderate earthquake of M 4.7 near Brawley, Southern California joined a number of light foreshocks
and aftershocks today in the area. NEIC reported the mainshock which occurred
local solar midnight may have caused slight damage with intensity VI in Brawley, California
with IV in Holtville, Imperial, Calipatria, Vista and III in San Diego, El Cajon, El Centro and La Mesa and in Cibola, Arizona.
Other moderate quakes in the series included events of M 4.5 and M 4.0 as foreshocks of the M 4.7.
Earthquakes in this area are often associated with swarms with larger earthquakes
in the middle of the sequence so additional activity in this swarm is expected
today and tomorrow.
This is an area which had been expected to see enhanced seismicity at this time as noted in the previous issue
of this summary.
"An M 3.1 in Baja and Southern California at 22:13 UT also occurred
and may indicated instability in that area leading to enhanced seismicity
in the next day or so." (May 8-9, 2026)
The last earthquake within about 100 km of this epicenter in Southern California
with M>=4.7 occurred as an M 4.9 on May 12, 2024 although an M 5.2 did occur
about 100 km west of this on April 14, 2025. At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 4.9-5.0 in Baja California
near the border with California (US), It was widely felt with intensity up to
VI in the region of Delta, Baja California, Mexico. EMSC reported light to moderate
shaking in Southern California in Calexico, El Centro, Carlsbad, Oceanside, in Arizona at Yuma; Holtville and in Baja California in Mexicali.
Numerous foreshocks and aftershocks were felt in the Delta Baja California region of Mexico with light to moderate intensity (II-IV).
The M 4.9 is the strongest earthquake in Baja within about 200 km of this event in more than three years.
An M 4.8 hit the same epicenter on March 31, 2021. The series began with a
light event of M 2.4 that occurred at the height of the strongest solar flare
of the day - an X1.0 which peaked at 16:35 UT. An earthquake of M 3.9 off the
coast of Honshu, Japan also occurred with the peak of this X1.0 class flare
at 16:37 UT. A similar simultaneity of the foreshock to this event occurred
with M 4.1 on May 8, 2024 and an X-class solar flare. At the time this summary noted
this as:
"The strongest earthquake in the U.S. or Canada today was an M 4.1 on the
border between Southern California and Baja California. This earthquake
was closely associated with a series of strong solar flares beginning
with flare 270 (C9.3) around 01:00 UT and ending with flares 280 and 290 (about 01:15-01:35 UT) - an X1.0 class flare.
It is likely it was promoted by SFE from those sources. (May 8, 2024)
This swarm in Baja California began at the end of flare 2400 - the largest
of the day and was probably precipitated by SFE from that flare. ..." (April 14, 2025) SWPC
The lst event with significantly larger magnitude within the area of today's
swarm was an M 5.3 on June 5, 2021.
Forecasts 181793 had expected an event within about 10-25 km of this epicenter with magnitude
up to M 4.8 was possible around May 3 or May 9, 2026.
P: 03MAY2026 181793 32.9N 115.6W 2.5-4.8 CAAAA So. California
P: 09MAY2026 181793 32.8N 116.0W 2.5-4.6 AAAAA So. California
Following is a listing of events of M>=3 in this sequence. A more extensive
listing of events of M>=2 can be found in the "Data" section of this summary.
O: 10MAY2026 07:10:21 32.9N 115.6W MB=4.7 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 03:39:29 32.9N 115.6W MB=4.5 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 03:13:23 32.9N 115.6W MB=4.0 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 02:22:08 32.9N 115.6W MB=4.4 NEIC SOUTHERN CALIFORNIA
O: 10MAY2026 00:34:13 32.9N 115.6W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 06:02:25 32.9N 115.5W ML=3.3 EMSC SOUTHERN CALIFORNIA
O: 09MAY2026 23:14:16 33.0N 115.6W ML=3.4 EMSC SOUTHERN CALIFORNIA
O: 09MAY2026 23:49:12 33.0N 115.6W ML=3.5 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 00:36:10 33.0N 115.6W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 02:22:07 33.0N 115.6W Mw=4.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 03:13:23 33.0N 115.6W Mw=3.9 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 03:39:29 33.0N 115.6W Mw=4.3 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 03:44:09 33.0N 115.6W ML=3.5 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 05:51:15 33.0N 115.5W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 06:36:25 33.0N 115.6W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 06:43:51 33.0N 115.6W ML=3.2 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:10:20 33.0N 115.6W Mw=4.7 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:14:38 33.0N 115.6W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 10MAY2026 07:41:25 33.0N 115.6W ML=3.2 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 5.5 in Bio-Bio Central Chile near Canete was felt with intensity up to II-III in the area(s) of Central Chile near Canete in Bio-Bio with V in Nacimiento, Canete, Coronel, Penco, Angol, Araucania and IV in Cabrero, Collipulli, Los Angeles, Arauco, and Chiguayante.
EMSC reported moderate to strong shaking in Chile in Angol, Lebu, Los Angeles, Coronel, Chiguayante, Concepcion, Talhuano, Carahue, Chillan.
The last earthquake with M>=5.5 within about 200 km of this epicenter
in Chile occurred as an M 5.9 on December 24, 2023 and prior to tha as an M 5.7 and M 6.2
on November 13, 2022. At the time this summary noted:
"The strongest earthquakes in the world today were M 6.2-6.3 events in the Bio-Bio area of Central Chile. NEIC reported it was felt with maximum intensity in Bio Bio at Lebu, Curanilahue; V in Arauco, Concepcion, Nacimiento; IV in Lota, Coronel, Chiguayante and lesser intensity III in Canete, Chile.
The mainshock was preceded by a foreshock of M 5.7 about a minute earlier. The University of Chile reported
a second event of M 6.2 a few seconds prior to this - making a series of three
moderate to strong events in this set. No major damage or tsunami was reported with
these earthquakes. The foreshocks were reported by NEIC to have been felt with intensity V in Concepcion; IV in Arauco and Pitrufquen and II in Talcahuano. Bio Bio, Chile.
This event was probably promoted by high tidal stresses as it occurred near
local solar midnight when these stresses area maximized. The M 4.9 aftershock
occurred within 2 minutes of local solar midnight. The last earthquake in Bio-Bio
Chile within about 150 km of these epicenters with M>=6.2 was an M 6.4 on September 21, 2021 and prior to that an M 6.4 on June 20, 2015.
At the time of the M 6.4 in September, 2021 this summary noted in this regard:
"The strongest earthquake in the world today was an M 6.4-6.6 in Central Chile in the region of Bio-Bio. NEIC reported this event was felt with maximum intensity VII in Bio-Bio at Arauco; IV in Lebu, and II-III in Talcahuano, Coronel, Concepcion, Chiguayante, Tome, Laja, Nacimento and in Angol. Araucania.
GUC reported this earthquake was felt with intensity V in Bio-Bio at Chiguayante, Coronel, Florida, Hualpen, Lota, Santa Juana, Talcahuano, Tome; IV in Concepcion and III in Cabrero, Yumbel, Lebu, and in Nuble with V in Portezuelo and Trehuaco; IV in Yungay, Coelemu and III inChillan and Quillon, Chile.
This is the culminating earthquake of a series which began at this epicenter two days
ago. This summary noted this series in the previous issue as:
"An earthquake in Central Chile of M 5.1 in the Bio-Bio area was felt today. NEIC reported intensity IV in Bio Bio at Coronel, and II-III in Talcahuano, Angol, Araucania and Valdivia, Los Lagos, Chile.
A smaller event hit the same region yesterday. This is an area which has often
seen seismicity associated with the new or full moon tides. A larger earthquake
is possible following this activity with the full moon in the next several days.
The last earthquake within about 150 km of this epicenter with M>=5.1 occurred
more than a year ago on March 25, 2020, an aftershock of an M 5.6 on March 17, 2020." (September 20-21, 2021, November 13, 2022)
This epicenter is at 103 degrees from Vanuatu and at the fourth node (90 degrees)
from Tonga, and may have been promoted by energy from those sources.
O: 10MAY2026 02:34:07 37.7S 73.3W MB=5.5 NEIC BIO-BIO, CHILE
O: 10MAY2026 02:34:07 37.7S 73.1W MW=5.5 EMSC BIO-BIO, CHILE
O: 10MAY2026 08:03:57 37.8S 73.3W MB=4.7 EMSC BIO-BIO, CHILE
NEIC reported an earthquake of M 4.2 in Cook Strait, New Zealand was felt with intensity up to II-III in the area(s) of Cook Strait, New Zealand near Dannevirke.
This earthquake occurred within minutes of local solar noon and may have been
promoted by tidal and/or geomagnetic stresses which maximize near this hour.
GeoNet reported the following data for this event.
O: 10MAY2026 00:44:25 40.2S 176.5E ML=4.3 GEONET Felt with moderate to light intensity in the area southeast of Wellington, New Zealand and in southern North Island and northern South Island. 44 reports of felt events were made of which 25 reported weak and 13 light intensity with 5 reports of moderate shaking and 1 with strong and 0 severe and 0 with extreme intensity came from the area.
O: 10MAY2026 00:44:25 40.2S 176.4E MB=4.2 NEIC COOK STRAIT, NEW ZEALAND
O: 10MAY2026 00:44:25 40.2S 176.5E ML=4.1 EMSC NORTH ISLAND OF NEW ZEALAND
NEIC reported an earthquake of M 4.9 in North Island, New Zealand was felt with intensity up to II-III in the area(s) of North Island, New Zealand in Wanganui Manawatu.
This epicenter is at the sixth node (60 degrees) from the Molucca Sea and at the
fifth node (72 degrees) from Malaysia and may have been promoted by energy
from those sources.
O: 09MAY2026 21:52:46 38.8S 175.2E MB=4.9 NEIC NORTH ISLAND, NEW ZEALAND
O: 09MAY2026 21:52:48 38.7S 175.3E MB=4.9 EMSC NORTH ISLAND OF NEW ZEALAND
NEIC reported an earthquake of M 4.3 in Alberta Canada was felt with intensity up to II-III in the area(s) of Alberta Canada with IV in Smoky Lake; III in Lac la Biche and II in Athabasca, Two Hills, Beaumont, Wood Buffalo, Edmonton and Saint Paul.
EMSC reported it was felt and heard in Lac La Biche, Canada.
O: 09MAY2026 15:05:05 54.0N 112.6W MB=4.3 NEIC ALBERTA, CANADA
O: 09MAY2026 15:05:05 54.0N 112.6W MB=4.3 EMSC ALBERTA, CANADA
NEIC reported an earthquake of M 4.4 in India was felt with intensity up to II-III in the area(s) of in India near Bilasipara.
EMSC reported moderate shaking in India at Bilasipara, Goshaingaon, Goalpara, Abhayapuri, Koch Bihar, in Thimphu, Bhutan and in Bangladesh at Lalmonirhat.
This epicenter is at the eighth node (45 degrees) from Honshu, Japan and may
have been promoted by energy from that source.
O: 09MAY2026 09:10:06 26.2N 90.2E MB=4.4 NEIC INDIA
O: 09MAY2026 09:10:08 26.2N 90.1E MB=4.4 EMSC ASSAM, INDIA
NEIC reported an earthquake of M 3.2 in Southern Australia was felt with intensity up to II-III in the area(s) of Southern Australia near Mirboo North.
O: 09MAY2026 08:12:43 38.4S 146.1E MB=3.2 NEIC SOUTHERN AUSTRALIA
O: 09MAY2026 08:12:41 38.5S 146.2E ML=3.2 EMSC NEAR S.E. COAST OF AUSTRALIA
EMSC reported an earthquake of M 4.5 in Panama-Costa Rica border was felt with intensity up to IV in the area(s) of Panama-Costa Rica bordern in El Palmar, Panama.
O: 09MAY2026 20:26:12 8.6N 82.9W MB=4.5 EMSC PANAMA-COSTA RICA BORDER REGIO
O: 09MAY2026 08:26:09 8.3N 82.9W ML=4.4 EMSC PANAMA-COSTA RICA BORDER REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-10 00:00 UT 10.1N 131.9E 35 kts North Pacific
Tropical Storm Hagupit continued today in north Pacific area with winds up to 35 kts west of Guam. This storm is expected to dissipate in the next day and not to threaten Islands in the northwest Pacific at this time. No sigificant seismicity is likely to be promoted with this storm. The antipode is at 10S 48W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
2040 0011 0021 0029 C1.3 (May 9, 2025) 1.1E-03
Admiralty Is. M 4.6 10:10 UT
2050 0141 0148 0156 C1.0 (May 9, 2025) 9.2E-04
2060 0218 0228 0238 C2.1 (May 9, 2025) 2.1E-03
2070 0321 0331 0339 C2.3 (May 9, 2025) 1.8E-03
2080 0514 0521 0526 C1.4 (May 9, 2025) 1.1E-03
2090 0622 0633 0642 C1.5 (May 9, 2025) 1.7E-03
Tarapaca M 4.2 06:29 UT
Los Angeles, CA M 3.2 06:32 UT
2100 0753 0802 0806 C1.6 (May 9, 2025) 1.0E-03
2110 0919 0924 0926 C1.2 (May 9, 2025) 5.8E-04
Honshu M 4.0 09:19 UT
2150 1315 1319 1324 C1.3 (May 9, 2025) 7.6E-04
2160 1359 1417 1422 C1.5 (May 9, 2025) 2.2E-03
South Sandwich Is. M 5.1 14:22 UT
2170 1516 1526 1535 C1.5 (May 9, 2025) 1.6E-03
2180 1620 1625 1627 C1.1 (May 9, 2025) 5.6E-04
Ryukyu Is. M 4.6 16:19 UT
2190 1848 1855 1912 C1.2 (May 9, 2025) 1.8E-03
2210 1912 1920 1930 C1.1 (May 9, 2025) 1.4E-03
2200 2021 2029 2032 C1.2 (May 9, 2025) 8.3E-04
Panama M 4.5 20:26 M 3.8 20:24 UT
2220 2137 2146 2157 C2.0 (May 9, 2025) 2.6E-03
Sumatra M 4.9 21:41 UT
North Island, New Zealand 21:52 UT
2230 2157 2203 2209 C2.1 (May 9, 2025) 1.7E-03
Java M 4.0 22:09 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 10-12. Solar M-flare chance: 40% X-class: 10% proton storm: 1%
AP Indicies: global: 5, high: 6, mid-latitude: 5, time of max k: 12:00 UT; Max k: 4 Global Kp 2.33 0000-0300, May 9; Sunspot Number: 81; Radio Flux: 122
May 9, 2026
Notable earthquakes and events:
A strong excursion in the geomagnetic field strength was recorded on May 8, 2026
on the GOES 18 magnetometer raising the field strength to about 150 nT (about 1/3rd)
increase over minutes before) at 21:50 UT. The satellite position was corrected
with an arcjet maneuver and by 22:42 normal operations resumed.
Seismicity associated with the geomagnetic event included an M 3.9 in Oaxaca, Mexico at 21:52 UT
and the beginning of a strong series in the Admiralty Islands (PNG) beginning
at 21:19 UT. An M 3.1 in Baja and Southern California at 22:13 UT also occurred
and may indicated instability in that area leading to enhanced seismicity
in the next day or so. A lesser excursion was recorded at 15:25 to 15:40 UT
on bothe Goes-10 and GOES-18 magnetometers. These were associated with an M M 4.6
in Ecuador; an M 3.5 in O'Higgins, Chile and an M 4.0 in Central Peru. These
epicenters were near local solar noon at the time and may have been
promoted by geomagnetic effects.
An earthquake of M 4.8 (not felt) did occur today in Central Peru in
connection with a moderate solar flare. This event occurred within
a few minutes of local solar noon and was probably promoted by
SFE associated with flare 1920 (C1.0) which data from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1920 1713 1716 1721 C1.0 (May 8, 2026) 5.7E-04
Central Peru M 4.8 17:14 UT
O: 08MAY2026 17:14:39 15.0S 75.7W ML=4.8 EMSC CENTRAL PERU
O: 08MAY2026 17:14:39 15.1S 75.7W MB=4.8 EMSC NEAR COAST OF CENTRAL PERU
The strongest earthquake in the world today was an M 5.9 in the South Indian
Ocean. It was not reported felt in this remote area. This could promote
minor activity near the antipode in eastern Nebraska to Iowa. If such an event
were to occur it may be in association with a stronger earthquake off the
coast of Northern California as such events often occur synchronously.
This earthquake occurred near local solar noon and may have been promoted
by tidal and/or geomagnetic stresses which maximize near this hour.
The only comparable earthquake at this magnitude level within about 300
km of this epicenter in the Southeast Indian Ridge in the past 35 years
occurred as an M 5.9 on October 14, 2018. At the time this summary noted:
"The strongest earthquake in the world today was a second in the region of the southeast Indian Ridge.
Today's event of M 5.9 followed an M 5.8 near this epicenter yesterday.
In the previous issue of this summary it was noted in this regard:
"A moderately large earthquake of M 5.8 hit the region of the Southeast Indian
Ridge today. It was not reported felt in this remote oceanic area. The last
and only other such event in this region within about 300 km of this epicenter
was an M 5.9 on October 8, 2002. The antipode of today's earthquakes is at
42N 92W in the general region of Iowa and Illinois, central U.S. Some minor
seismicity may occur in this area in the next several days should the Indian
Ocean activity continue." (October 14, 2018)
O: 08MAY2026 07:17:44 43.3S 91.7E ML=5.9 NEIC SOUTHEAST INDIAN RIDGE
O: 08MAY2026 07:17:43 43.5S 91.5E MB=5.9 EMSC SOUTHEAST INDIAN RIDGE
An earthquake of M 2.8 was recorded near the antipode of the event in the Indian Ridge in the
area of eastern Nebraska. NEIC reported it may have been lightly felt near Cowles, Nebraska.
It may have been promoted by energy from the Indian Ridge event and may have
been precursory to events of M 5.8 in the Rat Islands and M 5.0 off the
coast of Northern California (see below) about an hour later. This is a pattern which
has been described in this summary in previous issues.
O: 09MAY2026 03:09:52 40.1N 98.4W ML=2.8 NEIC SOUTHEAST NEBRASKA
O: 09MAY2026 03:09:52 40.2N 98.4W ML=2.8 EMSC NEBRASKA
The most widely felt earthquake in the U.S. or Canada today was an M 4.9 off the coast of northern California.
NEIC reported it was felt with intensity III in California at Whitethorn, McKinleyville, Ferndale, Martinez and in Brookings, Oregon and with intensity II in Northern California at Sacramento, Napa, Fortuna, Kneeland and Crescent City.
The last earthquake within about 150 km of this epicenter off the coast of northern California
with M>=5.0 occurred as an M 5.8 and aftershock of M 5.1 on September 9, 2025 about 200 km northwest of today's epicenter.
At the time this summary noted:
"A moderately strong M 5.8 earthquake occurred today off the coast of Oregon (US). NEIC reported maximum intensity III in Walnut Grove, British Columbia, Canada and Coos Bay, Oregon with lesser shaking in San Francisoc, California and in British Columbia at Victoria and Parksville.
An aftershock of M 4.9 was also felt lightly along the coast of Oregon and as far
as British Columbia. ...
The M 5.8 is the strongest earthquake in this area off the coast of Oregon within about 150 km of this epicenter since an M 5.9 on June 4, 2021.
At the time this summary noted:
"Today's activity of M 5.9 occurred within about half an hour of local solar
midnight with a strong aftershock near local solar noon of M 4.7. Tidal
stresses maximize near these hours and these were probably enhanced by
those stresses. The last earthquake of M>=5.9 within about 200 km of
today's epicenters occurred on September 5, 2019 with M 5.9 following an
M 6.4 on August 29, 2019. These events were about 200 km northwest of
today's activity. The last such event within about 150 km of today's
epicenter were an M 7.1 on June 15, 2005 and an M 6.2 on July 24, 1996.
When the M 6.4 occurred on August 29, 2019 this summary noted in this regard:
"This is the strongest earthquake off the coast of Oregon within about 250
km of this epicenter in more than 10 years - since an M 6.3 on January 10, 2008
and prior to that an M 6.3 on January 16, 2003. The only event in the region
with greater magnitude in the past 30 years was an M 6.9 on July 13, 1991." (September 5, 2019, June 4, 2021)
...
The last earthquake of M>=5.6 off the coast of Oregon within about 100
km of today's epicenter occurred on March 27, 2024. ..." (September 9, 2025)
Surface wave and a number of reflected S-phases
from the Rat Islands M 5.8 16 minutes earlier (see below) were at the epicenter in Northern California at the
time that earthquake occurred 16 minutes later according to travel time
curves. This makes the event in northern California a prime suspect
for dynamic triggering from seismic waves.
This epicenter is at 103 degrees from the Molucca Sea M 7.5 of April 1, 2026
and may have been promoted by energy from that source.
O: 09MAY2026 04:58:00 41.5N 125.3W ML=4.9 NEIC OFFSHORE NORTHERN CALIFORNIA
O: 09MAY2026 04:58:00 41.5N 125.3W ML=5.0 EMSC OFFSHORE NORTHERN CALIFORNIA
The strongest earthquake in the U.S. or Canada today, however, was an M 5.8
in the sequence in the Rat Islands, Aleutians, Alaska. This epicenter is
located about 150 km east of the swarm which has hit the Rat Islands over the
past several weeks. NTIC reported today's M 5.8 in Alaska was probably felt
in Adak, Alaska. A foreshock of M 4.7 occurred hours earlier. The last earthquake of M>=5.8 in the Rat Islands, Alaska
Was an M 6.4 about 150 km to the west of today's epicenter on March 4, 2026 but
the last closer than this was an M 5.9 on August 28, 2025 about 150 km north of
today's epicenter. This earthquake is located at 38.6 degrees from the subsequent
M 5.0 off the coast of northern California. The surface wave and a number of reflected S-phases
from the Rat Islands were at the epicenter in Northern California at the
time that earthquake occurred 16 minutes later according to travel time
curves. This makes the event in northern California a prime suspect
for dynamic triggering from seismic waves.
O: 09MAY2026 07:12:45 51.0N 179.3E ML=4.2 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 09MAY2026 04:42:20 51.1N 179.3E MW=5.8 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 09MAY2026 04:42:23 51.1N 179.3E ML=5.8 NEIC RAT ISLANDS, ALASKA
O: 08MAY2026 20:03:26 51.1N 179.3E mb=4.7 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 08MAY2026 20:03:25 51.1N 179.4E ML=4.7 NEIC RAT ISLANDS, ALASKA
NEIC reported an earthquake of M 3.4 in Greater Los Angeles, California was felt with intensity up to II-III in the area(s) of Greater Los Angeles, California with IV in Loma Linda, III in Corona, Redlands, Grand Terrace, San Bernardino, Mentone, Anaheim, Moreno Valley, Colton.
O: 09MAY2026 06:32:27 34.2N 117.3W ML=3.2 EMSC GREATER LOS ANGELES AREA, CALI
O: 08MAY2026 12:53:00 34.0N 117.2W ML=3.1 EMSC GREATER LOS ANGELES AREA, CALIF.
O: 09MAY2026 01:40:23 34.0N 117.2W ML=3.4 NEIC GREATER LOS ANGELES, CALIFORNIA
O: 09MAY2026 01:40:23 34.0N 117.2W ML=3.2 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 5.6 in the Admiralty Islands, P.N.G. was felt with intensity up to II-III in the area(s) of the Admiralty Islands, P.N.G. near Lorengau.
These epicenters are at the fourth node (90 degrees) from the North
Geomagnetic Pole and at the sixth node (60 degrees) from the South Geomagnetic
pole and may have been promoted by constructive energy interference from
those sources.
O: 08MAY2026 12:22:31 2.9S 147.7E ML=5.6 NEIC ADMIRALTY ISLANDS, PAPUA NEW GUINEA
O: 08MAY2026 12:22:34 2.9S 147.7E Mw=5.6 EMSC ADMIRALTY ISLANDS REGION, P.N.G.
O: 08MAY2026 21:18:54 2.9S 147.7E mb=4.9 EMSC ADMIRALTY ISLANDS REGION, P.N.G.
O: 08MAY2026 12:38:41 3.0S 148.0E mb=4.9 EMSC ADMIRALTY ISLANDS REGION, P.N.G.
O: 08MAY2026 13:02:58 3.0S 148.1E mb=4.9 EMSC BISMARCK SEA
O: 08MAY2026 09:32:03 3.1S 148.0E mb=4.8 EMSC BISMARCK SEA
O: 08MAY2026 12:13:21 3.1S 147.8E mb=4.6 EMSC BISMARCK SEA
O: 08MAY2026 13:27:28 3.1S 148.0E mb=4.8 EMSC BISMARCK SEA
O: 08MAY2026 13:31:23 3.1S 148.0E mb=4.8 EMSC BISMARCK SEA
O: 08MAY2026 12:06:06 2.9S 147.9E MB=4.7 EMSC ADMIRALTY ISLANDS REGION, P.N.
EMSC reported an earthquake of M 4.2 in Tarapaca, Chile was felt with intensity up to IV in the area(s) of Tarapaca, Chile in Iquique.
O: 09MAY2026 06:29:12 19.7S 59.8E ML=4.2 EMSC TARAPACA, CHILE
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-09 00:00 UT 10.3N 133.3E 40 kts North Pacific
Tropical Storm Hagupit continued today in north Pacific area with winds up to 40 kts west of Guam. This storm is expected to dissipate in the next day and not to threaten Islands in the northwest Pacific at this time. No sigificant seismicity is likely to be promoted with this storm. The antipode is at 10S 47W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1810 0149 0154 0156 C1.0 (May 8, 2026) 4.4E-04
Lake Baykal M 4.4 02:00 UT
1840 0358 0403 0405 C1.1 (May 8, 2026) 4.5E-04
Andaman Islands M 4.5 03:53 UT
1860 1113 1120 1122 C1.0 (May 8, 2026) 5.3E-04
Mongolia M 4.7 11:38 UT
South Carolian M 2.3 11:26 UT
1890 1539 1551 1601 C4.2 (May 8, 2026) 3.7E-03
Central Peru M 4.0 15:42 UT
1920 1713 1716 1721 C1.0 (May 8, 2026) 5.7E-04
Central Peru M 4.8 17:14 UT
1940 1756 1802 1809 C1.5 (May 8, 2026) 1.1E-03
New Zealand M 4.4 17:55 UT
1950 1820 1825 1827 C1.1 (May 8, 2026) 5.7E-04
1960 1901 1907 1909 C2.1 (May 8, 2026) 7.3E-04
1970 1916 1921 1937 C1.2 (May 8, 2026) 1.4E-03
Taiwan M 4.2 1926 UT
Gulf of California M 4.0 19:36 UT
1980 2005 2021 2035 C2.6 (May 8, 2026) 3.4E-03
Rat Islands M 4.7 20:03 UT
2010 2200 2207 2210 C1.0 (May 8, 2026) 6.2E-04
Baja California M 3.1 22:13 UT
2030 2319 2328 2339 C2.4 (May 8, 2026) 2.3E-03
New Zealand M 4.0 23:45 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active May 9 unsettled May 10-11. Solar M-flare chance: 40% X-class: 10% proton storm: 1%
AP Indicies: global: 12, high: 12, mid-latitude: 12, time of max k: 16:00 UT; Max k: 4 Global Kp 3.33 1800-2100, May 8; Sunspot Number: 75; Radio Flux: 120
May 8, 2026
Notable earthquakes and events:
A strong and sudden geomagnetic disturbance was recorded on both GOES 18 and 19
magnetometers today. This involved a near doubling of the geomagnetic field
strength starting near 16:10 UT and a return to background levels at or bear 1930 UT.
This type of geomagnetic excursion often occurs with a strong geomagnetic
storm and K-values did increase during this event, but not to storm levels.
Sub-solar areas at the time of the commencement are near 60 West longitude
where seismicity may be temporarily enhanced. This includes areas of eastern
Caribbean (Virgin Islands, Puerto Rico) and some areas of western South America.
Major volcanic eruptions occurred today in Guatemala at Santa Maria and in Indonesia
at Mount Dukono in north Maluku Province. An ash cloud was ascending to more than 10,000
meters in this eruption which began about 07:41 local time. At least three
hikers were killed in the eruption along with several others injured. This event
occured within about 200 km of the M 7.4 in the Sea of Molucca of April 1, 2026
O: 07MAY2026 23:41 1.7N 127.9E ERUPT NEWS HALMAHERA, INDONESIA MT DUKONO
The major eartuption of Santa Maria volcano near Quetzaltenango, Guatemala
also continued today. This has been ongoing for several days. Ashfall and plumes rose up
to 3200 m and pyroclastic flows were also observed. A number of hikers
in the area have been evacuated. Santa Maria volcano is at a latitude which
is sub-solar at this time. The eruption may have been triggered by strong
vertical tidal stresses from the sun.
O: 06MAY2026 20:00 14.7N 91.5E ERUPT NEWS SANTA MARIA VOLCANO, GUATEMALA
The strongest earthquake in the world today was an M 5.9 in the South Indian
Ocean. It was not reported felt in this remote area. This could promote
minor activity near the antipode in eastern Nebraska to Iowa. If such an event
were to occur it may be in association with a stronger earthquake off the
coast of Northern California as such events often occur synchronously.
This earthquake occurred near local solar noon and may have been promoted
by tidal and/or geomagnetic stresses which maximize near this hour.
The only comparable earthquake at this magnitude level within about 300
km of this epicenter in the Southeast Indian Ridge in the past 35 years
occurred as an M 5.9 on October 14, 2018. At the time this summary noted:
"The strongest earthquake in the world today was a second in the region of the southeast Indian Ridge.
Today's event of M 5.9 followed an M 5.8 near this epicenter yesterday.
In the previous issue of this summary it was noted in this regard:
"A moderately large earthquake of M 5.8 hit the region of the Southeast Indian
Ridge today. It was not reported felt in this remote oceanic area. The last
and only other such event in this region within about 300 km of this epicenter
was an M 5.9 on October 8, 2002. The antipode of today's earthquakes is at
42N 92W in the general region of Iowa and Illinois, central U.S. Some minor
seismicity may occur in this area in the next several days should the Indian
Ocean activity continue." (October 14, 2018)
O: 08MAY2026 07:17:44 43.3S 91.7E ML=5.9 NEIC SOUTHEAST INDIAN RIDGE
O: 08MAY2026 07:17:43 43.5S 91.5E MB=5.9 EMSC SOUTHEAST INDIAN RIDGE
NEIC reported an earthquake of M 4.6 in Honshu, Japan was felt with intensity up to II-III in the area(s) of Honshu, Japan in Tochigi, Ibaraki, Tokyo, and II in Saitama Prefectures, Japan.
EMSC reported weak shaking in Urayasu City, Chiba Prefecture.
O: 07MAY2026 18:50:02 36.3N 140.0E ML=4.6 NEIC SE HONSHU, JAPAN
O: 07MAY2026 23:31:16 37.6N 141.4E MW=4.7 EMSC NEAR EAST COAST OF HONSHU,
The strongest earthquake in the U.S. or Canada today was an M 4.4 in the
Geysers area north of San Francisco, California. NEIC reported it was widely
felt in northern California with IV in Middletown, Kelseyvill, San Anselmo, Lower Lake; III in Calistoga, Saint Helena, Healdsburg, Hidden Valley Lake, Napa and San Francisco.
This event occurred near local solar midnight and may have been promoted
by tidal stresses which maximize near this hour. The last earthquake in the
Geysers area of northern California with M>=4.4 occurred as an M 4.7 on January
2, 2025. 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 events 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. ..." (January 2, 2025)
When a foreshock occurred yesterday, this summary noted:
"NEIC reported an earthquake of M 3.1 in the California Geysers of northern California was felt with intensity up to II-III in the area(s) of the California Geysers of northern California with IV in Middletown and II in Fairfield, Kelseyville and Healdsburg.
This is an active area and has been relatively quiet for several weeks. It
is due a moderate quake of M>=4 in the next several days, most likely
tidally related near local solar noon or midnight." (May 7, 2026)
O: 07MAY2026 09:42:43 38.8N 122.8W ML=4.4 NEIC NORTHERN CALIFORNIA
O: 07MAY2026 09:49:56 38.8N 122.7W MD=2.2 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:54:40 38.7N 122.7W MD=2.7 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:42:43 38.8N 122.8W ML=4.2 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:44:27 38.8N 122.8W MD=2.5 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 4.0 in Southern Colorado was felt with intensity up to II-III in the area(s) of Souothern Colorado in Weston, Trinidad, La Veta, Pueblo, Walsenburg, Pueblo, and in New Mexico at Cimarron, Arroyo Hondo, Questa, Raton.
EMSC reported tiw was felt lightly in Trinidad, Colorado. This is part of
an ongoing series that started in September, 2021. The tectonics of this
activity has not been well understood. The last earthquake in this series
of M>=4 occurred on August 26, 2023 with M 4.0 but the last event of significantly
larger magnitude was an M 5.3 on August 23, 2011. At the time this summary
noted the history of Colorado earthquakes as:
"... The strongest of these today occurred in the region of Southern Colorado after a smaller event occurred
earlier. The largest of the Colorado events was an M 5.3-5.4. This appears
to be the strongest earthquake in Colorado since an M 6.2 on November 8, 1882,
although an event of M 5.4 was also recorded in central Colorado on October 11,
1960. Other earthquakes in this distance zone today included events in
India and Kashmir, Tajikistan, Guatemala, and Chile among others. We had
anticipated this pattern in our summary yesterday as follows:
"Readers are advised to visit the daily earthquake map to see where further
activity may be likely. For example, the 103 degree line, the edge of the shadow
zone and the seventh node was active today from Chiapas, Mexico to central
Peru, Chile and the South Sandwich Islands. The line passed through Pakistan and Afghanistan
where activity occurred yesterday but where a further earthquake is possible
at this time ... The P103 theory suggests that triggering will occur at 103 degrees from
major earthquakes because seismic energy reflected and refracted off the
core-mantle boundary concentrates at this distance on the surface. Followers
of this theory may be interested that the earthquake of M 5.6 in the South
Sandwich Islands was at 103 degrees from Vanuatu as were a series of
events in Chiapas, Mexico including an M 4.5. Earthquakes in northern Peru (M 4.4),
and Atacama, Chile (M 4.7) were at 106 degrees from Vanuatu." (August 22, 2011)
Earthquakes of M 5.2-5.4 and M 4.6-5.0 hit southern Colorado near the New Mexico border today.
These events were felt throughout most of Colorado and in much of northern
New Mexico and as far as Kansas, Nebraska, Oklahoma, Texas and Wyoming. The larger event has only two
predecessor earthquakes in Colorado of stronger magnitude in historic times.
One of these was an artificially induced earthquake caused by water injection
which occurred with M 5.4 in the Denver area on October 10, 1960. An earthquake
in 1973 may have occurred in northwestern Colorado with M 5.7 but this is
not listed in the "Seismicity of the United States 1568-1989" and may have
had its epicenter in Wyoming as well where it is given an M 4.8 magnitude. While
a geophysicist with the USGS is reported as stating there was an M 5.7
in Colorado in 1973 this is clearly an error. There is no such event listed
in the definitive catalog of historical Colordao earthquake - "Colorado Earthquake
Data and Interpretations 1967 to 1985" by Kirkham and Rogers.
The only natural event of larger magnitude in Colorado history occurred near Denver on November
8, 1882 and while this event was felt strongly in northern Colorado, it is
possible the epicenter was actually in southern Wyoming.
Initial reports indicated that a few homes were damaged and rockslides hit
highways in the epicenral region.
...
Most of the lighter events in the series today also were felt lightly
in the epicentral zone.
When the light precursor hit the region earlier this morning we discussed
this series of events leading up to today's moderately strong earthquake
in this summary as follows:
"An earthquake of M 2.9 was lightly felt in southern Colorado near the
New Mexican border today. This series of unexplained earthquakes began
exactly 10 years ago in late August (28), 2001 and has continued off and on
since that time. The strongest earthquakes in the sequence typically
occur in August and September with an M 5.0 on August 10, 2005, the largest
to date and an M 4.5 on September 5, 2001 the second to date. The last
event of M>=2.5 in the area was an M 3.8 on May 11, 2011 and an M 3.2
on March 12, 2011 shortly after the great Japanese earthquake. Since today's
event followed a strong aftershock of the Japanese event by about the same
time as the earthquakes in March, some triggering may be considered in
these cases." (August 22, 2011, August 22, 2011)
Today's earthquake occurred near local solar noon at the end of a major geomagnetic
excursion and may have been promoted by that geomagnetic variation (see above).
This event occurred near the peak of that geomagnetic anomaly.
The M 5.3+ earthquake on August 22, 2011 was not the only unusual geophysical
event on that date. It was disclosed at a later time in a peer reviewed journal that the one strongest
Gamma Ray Burst (GRB) (or other stellar explosion) on record also occurred on that date. Later on the
same date an M 5.8 hit the region of Virginia (US) causing major damage
to monuments and structures in Washington D.C. At the time this summary
discussed this in part as:
"A moderately strong earthquake of M 5.8 hit Virginia and Washington D.C.
today and was felt from New Brunswick, Canada to Florida and as far inland as the central
United States. This is the second moderately strong and highly unusual
earthquake to hit the North American plate in less than 12 hours, the
first being an earthquake in Colorado of M 5.4 earlier in the day. We
discussed the Colorado quake in our previous summary. Aftershocks in Colorado
continued throughout the day today. In a curious historical coincidence,
the last major earthquakes in Colorado occurred in September, 2001 several
days before the destructive attacks on 9-11, 2001 in New York and Washington D.C.
The strongest aftershock of the M 5.8 in Virginia was an M 4.2 with
other light aftershocks recorded of M 3.4 and 2.8 in the first few hours.
This is the strongest earthquake ever recorded in this region of the
United States. The only other events of M>5 in the area occurred with M 5.0
on August 27, 1833 (an event also associated with a hurricane to the southwest)
and an M 5.0 on December 23, 1875. Both of these occurred within 40 km
of today's epicenter, the only epicenter in the region which has shown
significant seismicity over the past three centuries. In the broader area
including Virginia, West Virginia, Washington, D.C., Maryland, Delaware,
North Carolina the only event of similar or larger size ever recorded was
the Giles, Virginia earthquake of May 31, 1897 of M 5.8." (August 23, 2011)
It is entirely consistent that this activity was triggered by effects from
the GRB of the same date. That GRB was apparently related to Super nova 2011fe, a type 1a supernova
in the in the Pinwheel Galaxy (M101) from images taken on 22 and 23, August 2011 at the Palomar Transient Factory survey, the youngest Type 1a supernova ever discovered.
The GRB Catalog (SWIFT) is not currently being updated daily but the unusual geomagnetic anomaly observed on GOES
magnetometers today (see above) is consistent (but not proven at this time)
with a major GRB or gravity wave. Such an event could be associated with an eruption of
the star Betelguese which some astronomers believe has gone or is undergoing
nova or supernova precursors as of today. If so, this event would mark
a major date in observational astronomy.
Tday's event in Colordo and New Mexico may have been triggered by SFE
associated with solar flare 1710 which began the same minute as the
earthquake in Colorado. This C6.0 solar flare was the third most energetic flare
recorded in the past six days. Data on this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1710 1744 1757 1813 C6.0 (May 7, 2026) 8.8E-03
Colorado M 4.4 17:44 UT
O: 07MAY2026 17:44:24 37.0N 104.9W ML=4.0 NEIC TRINIDAD, COLORADO
O: 07MAY2026 17:44:24 37.0N 104.9W MW=4.0 EMSC NEW MEXICO
NEIC reported an earthquake of M 4.7 in the Central Mid-Atlantic Ridge was not felt today.
This event coincided with the beginning of the strong geomagnetic excursion
(see above) near local solar noon and may have been promoted by that
geomagnetic event. The antipode of this epicenter has been active with a
major tropical cyclone passing through the area a week ago and with
several moderately strong seismic events since then. A possible enhancement
could occur near the antipode of the Central Mid-Atlantic in the area near
Papua New Guinea in the next couple of days.
O: 07MAY2026 16:54:03 7.5N 34.6W ML=4.7 NEIC CENTRAL MID-ATLANTIC
O: 07MAY2026 16:54:03 7.5N 34.6W MB=4.7 EMSC CENTRAL MID-ATLANTIC RIDGE
NEIC reported an earthquake of M 3.1 in Barstow, Central California was felt with intensity up to II-III in the area(s) of Barstow, Central California in Rancho Cucamonga, Victorville and Barstow.
This event coincided with the beginning of the strong geomagnetic excursion
(see above) near local solar noon and may have been promoted by that
geomagnetic event.
O: 07MAY2026 16:37:46 35.0N 117.0W ML=3.1 NEIC CENTRAL CALIFORNIA
O: 07MAY2026 13:59:57 35.3N 117.8W ML=2.6 EMSC SOUTHERN CALIFORNIA
O: 07MAY2026 16:37:46 35.1N 117.0W ML=3.0 EMSC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 4.4 in Turkey-Iran Border region was felt with intensity up to IV in the area(s) of Turkey-Iran Border region in Khowy, Tabriz, Iran.
O: 08MAY2026 03:47:23 38.4N 45.0E ML=4.4 EMSC TURKEY-IRAN BORDER REGION
EMSC reported an earthquake of M 4.4 in Lake Baykal region, Russia was felt with intensity up to IV in the area(s) of Lake Baykal region, Russia in Zarechnyy.
It was preceded by an M 4.0 foreshock.
O: 08MAY2026 02:57:55 53.3N 108.6E MB=4.5 EMSC LAKE BAYKAL REGION, RUSSIA
O: 08MAY2026 02:00:36 53.5N 108.6E mb=4.4 EMSC LAKE BAYKAL REGION, RUSSIA
O: 08MAY2026 01:46:21 53.4N 108.6E ML=4.0 EMSC LAKE BAYKAL REGION, RUSSIA
EMSC reported an earthquake of M 4.6 in southern Honshu, Japan was felt with intensity up to IV in the area(s) of southern Honshu, Japan near Kanaya.
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.
O: 08MAY2026 03:36:10 35.0N 138.1E ML=4.2 EMSC NEAR S. COAST OF HONSHU, JAPAN
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-08 00:00 UT 8.7N 138.9E 50 kts North Pacific
Tropical Storm Hagupit continued today in north Pacific area with winds up to 50 kts southwest of Guam in the Caroline Islands. This storm is moving to the WNW with winds up to 50 kts. It is unlikely to trigger seismicity in Guam but may promote some in the Caroline Islands. The antipode is at 9S 41W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1640 0128 0215 0430 C4.5 (May 7, 2026) 2.2E-02 *
Northern California M 3.1 03:56 UT
Kamchatka M 4.8, M 4.3 01:10, 04:15 UT
New Guinea M 5.1 01:23 UT
1650 1035 1045 1053 C2.3 (May 7, 2026) 1.8E-03
Guerrero M 4.0 10:32 UT
1660 1253 1259 1303 C1.5 (May 7, 2026) 8.5E-04
Argentina M 4.0 12:51 UT
1680 1420 1514 1540 M2.6 (May 7, 2026) 8.1E-02
Los Angeles, California M 2.0 14:23 UT
1710 1744 1757 1813 C6.0 (May 7, 2026) 8.8E-03
Colorado M 4.4 17:44 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active May 8-9 unsettled May 10. Solar M-flare chance: 45% X-class: 10% proton storm: 1%
AP Indicies: global: 7, high: 4, mid-latitude: 6, time of max k: 18:00 UT; Max k: 3 Global Kp 3.33 1800-2100, May 7; Sunspot Number: 59; Radio Flux: 117
May 7, 2026
Notable earthquakes and events:
It was a relatively quiet day in the earth's environment today. The AP was 4
with k not exceeding 1.0 all day. GOES magnetometers showed smooth variations
without significant excursions. There were no proton or electron storms.
Global seismicity was also at relatively quiet levels. The strongest earthquakes
in the world occurred near the International Date line (IDL) with an M 5.8 in the Rat Islands, Alaska and in the Kermadec Islands with M 5.3 and M 5.6 and as an M 5.5 at local solar midnight
in Mindanao, Philippines and were probably promoted by tidal stresses.
A Tropical Storm (Hagupit) formed in the North Pacific south of Guam but is not strong enough to affect
seismicity at this time. One c-class solar flare (C4.3) was reported, but
did not spike in the X-ray flux. Rather it was a broad increase and decrease
and was not likely to significantly affect global seismicity.
The strongest earthquake of the day in the world was an M 5.8 in the Rat Islands,
Aleutians. NEIC reported it may have been felt with intensity up to IV near
Attu Station, Rat Islands, Alaska. It occurred near local solar midnight
and may have been promoted by tidal stresses which maximize near this hour.
This is probably an aftershock the largest to date - of an M 6.4 that occurred on
March 4, 2026. At the time this summary noted:
"A strong M 6.4 earthquake struck the Rat Islands, Aleutians, Alaska today. NEIC
reported it was likely felt in the epicentral area with intensity up to VI.
This is the strongest earthquake in the Rat Islands within about 200 km of this
epicenter since an M 6.6 on October 8, 2017 and April 2, 2019 with M 6.4.
At the time this summary noted:
"The last earthquake in the Rat Islands of M>=6.5 was an M 6.6 on October 8, 2017.
Today's shallow focus event, however is the strongest at a shallow depth since an M 6.8 on June 14, 2005 in
the Rat Islands. An intermediate focus M 7.9 hit the region to the south on June 23, 2014, the
only other such regional events in the past 13 years." (April 2, 2019)
Today's event continues( and possibly is the culmination to) a strong swarm of earthquakes in the area reported in the
last two issues of this summary as:
"NEIC reported an earthquake of M 4.4 in the Rat Islands, Alaska was felt with intensity up to II-III in the area(s) of the Rat Islands, Alaska at Attu Station with likely intensity III.
These continue the current swarm in the area which began shortly before
the lunar eclipse on March 3, 2026. These events occurred near the longitude of maximum
tidal stress with this full moon and eclipse near local solar midnight and solar noon and
may have been promoted by tidal stresses. (see above)
These epicenters are located at the sixth node (60 degrees) from Mindanao and at the
third node (120 degrees) from the South Geomagnetic Pole and may have been
promoted by energy from those sources." (March 3-5, 2026)
O: 06MAY2026 14:15:32 52.2N 176.5E ML=5.8 NEIC RAT ISLANDS, ALASKA
O: 06MAY2026 14:15:32 52.3N 176.5E MW=5.8 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 06MAY2026 14:06:37 52.2N 176.4E mb=4.3 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
A moderately stron M 5.6 also occurred as an aftershock in southern Kermadec
Islands, New Zealand today. NEIC reported it may have been felt with intensity
up to VI in the remote epicentral area. Like the M 5.5 in Mindanao, Philippines
today, this earthquake occurred within a couple of minutes of local solar
midnight and was probably promoted by tidal stresses which maximize near
this hour. An aftershock M 5.3 followed on May 7.
This is likely a regional aftershock of the M 6.0 that hit the area on April 16, 2026 (with an aftershock of M 5.9 on
April 18, 2026). At that time this summary noted:
"The strongest earthquake in the world today was an M 6.0 in the Kermadec Islands. NEIC reported it may have been felt with intensity up to VI in the epicentral area of the Kermadec Islands, New Zealand.
This continues a series of moderate earthquake near this epicenter over the
past two weeks including events of M 5.5 and M 5.4 (among others) on April 5.
Tropical Cyclone Vaianu passed near today's epicenter on April 10-11, 2026
...
This is the strongest earthquake within about 200 km of this epicenter
since an M 6.6 on September 8, 2023. At the time this summary noted:
"The M 6.6 in the Kermadec Islands, New Zealand today was widely felt in North Island, New
Zealand - unlike most strong earthquakes in the Kermadec Islands. NEIC reported
maximum intensity for the M 6.6 at IV in Gisborne at Te Karaka and II-III in the Bay of Plenty at Opotiki, Whakatane, in North Shore, Auckland, Napier, Hawke's Bay, in Manawatu-Wanganui at Palmerston North and Shannon, and more than 1000 km away in Wellington at Porirua, Lower Hutt and Wellington.
This is the strongest earthquake in the Kermadec Islands within about 200
km of this epicenter since an M 6.6 on August 14, 2022 and an M 7.4 on June 18, 2020.
At the time of the August 14, 2022 event this summary noted:
"The strongest earthquake in the world today was an M 6.4-6.6 in the Kermadec Islands, New Zealand. It may have been felt lightly as far as North Island, New Zealand.
This is the second strongest earthquake in the world in the past month following
an M 7.0 in Luzon, Philippines on July 27. An M 6.6-6.8 also occurred in the
Easter Island region on July 12, 2022 and an M 7.2 hit southern Peru on May 26, 2022,
the last such events in the past three months. Today's event of M 6.6 is the
strongest earthquake within about 200 km of this epicenter in the southern Kermadec
Islands since an M 7.4 on June 18, 2020 and an M 6.9 on September 10, 2018 and an
M 6.8 on December 9, 2008." (August 14, 2022, September 8, 2023)
This earthquake occurred near local solar midnight and is consistent with triggering by
promotion by tidal stresses with the new moon of April 17 (see above). The
last earthquake in the earthquake of M>=6 occurred on April 4, 2026 as an
M 6.0 aftershock of the M 7.4 in the Molucca Sea of April 1, 2026 (with
the last full moon).
This epicenter is near the sixth node (60 degrees) from the Molucca Sea and at the fifth node (72 degrees)
from Malaysia and may have been promoted by energy from those sources." (April 16, 2026)
An earthquake of M 5.0 in the Fiji Islands also occurred within a couple
of minutes of local solar midnight on May 7, 2026. At a deep focus it was
not reported felt.
Today's M 5.6 epicenter is at the fifth node (72 degrees) from Malaysia
and near the sixth node (60 degrees) from the Molucca Sea and may have
been promoted by energy from those sources.
O: 06MAY2026 11:46:48 32.2S 177.9W ML=5.6 NEIC KERMADEC ISLANDS, NEW ZEALAND
O: 06MAY2026 11:46:49 32.3S 178.0W MW=5.6 EMSC SOUTH OF KERMADEC ISLANDS
O: 07MAY2026 11:48:41 17.9S 177.9W ML=5.1 NEIC FIJI REGION
O: 07MAY2026 11:48:41 18.0S 178.0W MB=5.1 EMSC FIJI REGION
O: 07MAY2026 08:53:28 27.4S 176.6W ML=5.3 NEIC KERMADEC ISLANDS, NEW ZEALAND
O: 07MAY2026 08:53:27 27.4S 176.6W MB=5.3 EMSC KERMADEC ISLANDS REGION
The most widely felt earthquake in the world today was an M 5.5 in Mindanao, Philippines near Baganga.
NEIC reproted intensity IV in Southern Mindanao at Andili and Davao with III in Panabo.
Lesser shaking was reported form Barra, Northern Mindanao and in Caraga, Philipines at Brsilisa, Bislig, Dapa.
EMSC reported strong shaking in Mindanao at Magugpo Poblacion, Limao and Davao.
This event occurred within a couple of minutes of local solar midnight
and was probably promoted by tidal stresses which maximize near this hour.
O: 07MAY2026 09:08:51 7.5N 126.7E ML=4.1 EMSC MINDANAO, PHILIPPINES
O: 06MAY2026 15:35:46 7.6N 126.8E Mw=5.5 EMSC MINDANAO, PHILIPPINES
O: 06MAY2026 15:35:46 7.6N 126.8E ML=5.5 NEIC MINDANAO, PHILIPPINES
NEIC reported an earthquake of M 2.8 in Washington State (US) was felt with intensity up to II-III in the area(s) of Washington State with III in Sedro Woolley and II in Victoria, British Columbia, Canada.
EMSC reported moderate shaking in Concrete, Washington.
O: 07MAY2026 05:20:07 48.5N 121.8W ML=2.8 NEIC WASHINGTON STATE
O: 07MAY2026 05:20:07 48.5N 121.8W ML=2.7 EMSC WASHINGTON
NEIC reported an earthquake of M 3.1 in the California Geysers of northern California was felt with intensity up to II-III in the area(s) of the California Geysers of northern California with IV in Middletown and II in Fairfield, Kelseyville and Healdsburg.
This is an active area and has been relatively quiet for several weeks. It
is due a moderate quake of M>=4 in the next several days, most likely
tidally related near local solar noon or midnight.
O: 07MAY2026 03:56:31 38.8N 122.7W ML=3.1 NEIC NORTHERN CALIFORNIA
O: 07MAY2026 09:54:40 38.7N 122.7W MD=2.7 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 03:56:31 38.8N 122.7W ML=3.1 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:42:42 38.8N 122.8W ML=4.0 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:44:27 38.8N 122.8W MD=2.5 EMSC NORTHERN CALIFORNIA
O: 07MAY2026 09:49:56 38.8N 122.7W MD=2.2 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.1 in the greater Los Angeles California area was felt with intensity up to II-III in the area(s) of the greater Los Angeles California area with III in Redlands, Riverside, Moreno Valley, Grand Terrace and II in Loma Linda.
EMSC reported moderate shaking in Redlands, Moreno Valley, Loma Linda, Grand Terrace, Highgrove, Riverside, Pedley, Oak Glen, Midway City, and Lancaster.
O: 06MAY2026 16:45:15 34.0N 117.2W ML=3.1 NEIC SOUTHERN CALIFORNIA
O: 06MAY2026 16:45:15 34.0N 117.2W ML=3.0 EMSC GREATER LOS ANGELES AREA, CALI
O: 07MAY2026 07:10:57 34.0N 117.2W ML=2.1 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 4.4 in Honduras was felt with intensity up to II-III in the area(s) of Honduras with II in Danli, El Paraiso and Tegucigalpa.
EMSC reported moderate to strong shaking in Honduras at El Chimbo, Santa Lucia and Tegucigalpa.
This epicenter was at nearly a sub-solar latitude for May 6 and could have been
triggered by solar tidal stresses which maximize at this latitude at this
time of year. Honduras, while seeing occasional moderate earthquakes is not
a highly seismic area. Today's event is the largest in Honduras within about
150 km of this epicenter since an M 4.4 on October 21, 2023 - an aftershock of an M 4.8 on October 14, 2023.
The last earthquake in this area of Honduras with significantly larger magnitude
was an M 5.5 (and aftershocks) on April 10, 2013. At the time this summary
noted:
"An unusually strong earthquake shook Honduras today. NEIC reported this earthquake (M 5.5)
was felt with intensity in northern Honduras of V in Tela, Atlantica and Agalteca, Francisco Morazan and IV in Mateo;
Intensity IV was also felt in Tegucigalpa, Utila, and Cortes at San Pedro Sula. Lesser shaking
of intensity II-III occurred in Honduras at Choloma, Comayagua, Coyoles, El Chimbo,
El Jicarito, El Jicaro, El Porvenir, El Pregreso, El Tablon,
French Harbor, La Ceiba, Mateo, Puerto Cortes, San Jose de Colinas, San Pedro
Sula, Siguatepeque, Valle de Angeles, Villanueva, Yaguacire, Arizona, Roatan, Santa Lucia
and Tegucigalpa and in Belize at Belize City. Testimonials at EMSC reported
panic in La Ceiba 40 km northeast of the epicenter and strong shaking
at Coxen Hole, and Tegucigalpa, Honduras. While this earthquake caused
some panic and concern there were no initial reports of damage in Honduras. The
epicenter was near the town of San Juan Pueblo in northern Honduras.
A strong earthquake of M 7.3 hit off northern Honduras on May 28, 2009
and did much damage. The strongest aftershock to date has been an M 5.4 on June
8, 2009. Today's event does not appear to be an aftershock of those
earthquakes as it occurred about 200 km to the southwest of those epicenters.
It is the strongest earthquake to occur within Honduras in at least five
years. The M 5.4 on June 8, 2009 was near this epicenter (about 50 km away)
and could have represented regional stress redistribution. The event of
June, 2009 hit on the day of the full moon and, like today's may have been
tidally triggered as it occurred within minutes of local solar midnight
(anti-solar) while today's event occurred near local noon (sub-solar)." (April 10, 2013)
O: 06MAY2026 10:42:41 14.8N 87.2W ML=4.4 NEIC HONDURAS
O: 06MAY2026 10:42:42 14.9N 87.2W MB=4.4 EMSC HONDURAS
NEIC reported an earthquake of M 4.4 in Southeastern Honshu, Japan was felt with intensity up to II-III in the area(s) of Southeastern Honshu, Japan with III in Wako, Saitama, Chigasaki, Kanagawa, Tokyo, and Yokosuka and II in Chiba at Kashiwa and Matsudo.
EMSC reported moderate shaking in Japan at Zama, Kawasaki, Tokyo, Nishitokyo, Kamagaya.
O: 06MAY2026 10:06:27 35.4N 139.4E ML=4.4 NEIC EASTERN HONSHU, JAPAN
O: 06MAY2026 10:06:27 35.5N 139.5E MW=4.4 EMSC NEAR S. COAST OF HONSHU, JAPAN
EMSC reported an earthquake of M 4.6 in Ecuador was felt with intensity up to IV in the area(s) of Ecuador at Cuenca.
O: 06MAY2026 22:06:49 2.2S 79.1W ML=4.6 EMSC NEAR COAST OF ECUADOR
EMSC reported an earthquake of M 4.5 in Arunchal Pradesh, India was felt with intensity up to IV in the area(s) of Arunchal Pradesh, India in Tinsukia and Duliagaon.
O: 06MAY2026 15:17:37 28.8N 95.9E ML=4.5 EMSC ARUNCHAL PRADESH, INDIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-07 00:00 UT 7.2N 142.9E 45 kts North Pacific
Tropical Storm Hagupit continued today in north Pacific area with winds up to 45 kts south of Guam. This storm is moving to the WNW with winds up to 45 kts. It is unlikely to trigger seismicity in Guam but may promote some in the Caroline Islands. The antipode is at 7S 37W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred 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 0128 0215 0430 C4.5 (May 7, 2026) 2.2E-02 *
Northern California M 3.1 03:56 UT
Kamchatka M 4.8, M 4.3 01:10, 04:15 UT
XXXX 0930 0940 1015 C1.1 (May 7, 2026) 2.2E-03 *
Northern California M 4.0 09:42 UT
Papua M 4.0 09:41 UT
1360 0433 0446 0457 C1.0 (May 6, 2026) 1.4E-03
1550 1719 1724 1729 C1.4 (May 6, 2026) 8.3E-04
Guatemala M 3.8 17:10 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active May 7-8 unsettled May 9. Solar M-flare chance: 15% X-class: 1% proton storm: 1%
AP Indicies: global: 3, high: 0, mid-latitude: 4, time of max k: 17:00 UT; Max k: 2 Global Kp 1.00 2100-2400, May 6; Sunspot Number: 105; Radio Flux: 120
May 6, 2026
Notable earthquakes and events:
A pair of unusual earthquakes occurred today in the Russian Ural Mountains. These events
were reported with M up to 4.7 with NEIC reporting M 4.4 and 4.2. They were not
immediately reported felt in the area near Cheremukhovo, Russia. This is not
a seismic area. Two earthquakes of M>=4.4 have been recorded within about 250
km of today's epicenters in the past 35 years - an M 4.7 on February 13, 2010 and an M 4.8 on January 5, 1995.
At the time of the February 2010 event (which occurred with a strong solar
flare of M8.3) this summary noted:
"A very unusual earthquake also hit with M 4.6 in the Ural Mountains of
Russia today. NEIC reported this earthquake was felt in the region of
Sverdlovsk, Russia with intensity III at Severouralsk, Serov and Karpinsk and II at
Krasnoturinsk, and Ivdel. Intensity II was also reported 200 km to the
west at Aleksandrovsk, Perm, Russia. This is the strongest earthquake in the Urals since an
M 4.8 on January 5, 1995." (February 13, 2020)
These events began near local solar midnight and may have been promoted
by tidal and/or geomagnetic effects which maximize near this hour.
The GOES 19 Magnetometer shows a strong variation in the earth's
geomagnetic field requiring an arcjet stabilization to the orbit of
that satellit at 22:00-22:10 UT.
These epicenters are at the seventh node (52 degrees) from Honshu, Japan and may
have been promoted by energy from that source.
O: 05MAY2026 22:02:01 60.3N 59.7E MB=4.4 NEIC URAL MOUNTAINS, RUSSIA
O: 05MAY2026 22:02:01 60.2N 59.8E MB=4.4 EMSC URAL MOUNTAINS REGION, RUSSIA
O: 05MAY2026 21:37:25 60.4N 60.0E mb=4.2 EMSC URAL MOUNTAINS REGION, RUSSIA
O: 05MAY2026 21:37:25 60.4N 60.1E MB=4.2 NEIC URAL MOUNTAINS, RUSSIA
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 with III in Palmer, Wasilla, Willow and Matanuska-Susitna Borough and II in Chugiak, Anchorage, Eagle River.
O: 06MAY2026 07:56:03 61.8N 149.3W MB=3.5 NEIC SOUTHERN ALASKA
O: 06MAY2026 07:56:04 61.8N 149.3W ML=3.4 EMSC SOUTHERN ALASKA
NEIC reported an earthquake of M 3.2 in Western Nevada was felt with intensity up to II-III in the area(s) of Western Nevada with II in Carson City, Sparks, Silver Springs, Dayton, Fernley and Fallon.
O: 06MAY2026 04:04:13 39.3N 119.1W MB=3.2 NEIC NEVADA
O: 05MAY2026 11:13:50 39.3N 119.1W ML=2.2 EMSC NEVADA
O: 06MAY2026 04:04:14 39.2N 119.2W Mw=3.4 EMSC NEVADA
NEIC reported an earthquake of M 4.3 in Costa Rica was felt with intensity up to II-III in the area(s) of Costa Rica in San Fafael, San Jose.
EMSC reported a slight rumble in San Fafael, Atenas and Daniel Flores.
O: 05MAY2026 20:54:44 9.3N 84.3W MB=4.3 NEIC COSTA RICA
O: 05MAY2026 20:54:44 9.4N 84.3W ML=4.5 EMSC COSTA RICA
NEIC reported an earthquake of M 5.0 in Northern Peru was felt with intensity up to II-III in the area(s) of Northern Peru in Guayas, Ecuador at Eloy Alfaro and Playas and in Cuenca, Azuay.
EMSC reported this event was felt with moderate to strong intensity in Ecuador at Santa Rosa, Loja, Guayaquil, and Cuenca.
O: 05MAY2026 15:58:27 3.5S 80.5W MB=5.0 NEIC NORTHERN PERU
O: 05MAY2026 15:58:26 3.5S 80.7W MB=5.0 EMSC PERU-ECUADOR BORDER REGION
NEIC reported earthquakes of M 2.6 and M 2.5 north of San Francisco, California were felt with intensity up to II-III in the area(s) of north of San Francisco, California with III in Crocket, San Pablo and Hercules and Fairfield, II in El Cerito, Hercules, San Pablo, Pinole, Rodeo, Richmond, Albany, Berkeley, Vallejo, and El Sobrante.
EMSC reported the event of M 2.5 was felt in Benicia with short duration.
The event at 14:57 UT May have been promoted by SFE from solar flare 1250 (C1.2)
which was first observed at the same time as the event in San Francisco.
Preliminary data on this solar flare from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1250 1458 1509 1512 C1.2 (May 5, 2026) 9.4E-04 *
Mid-Indian Ridge M 5.1 15:09 UT
San Francisco, California M 2.5 14:57 UT
O: 05MAY2026 15:22:26 38.2S 122.2W MB=2.6 NEIC NORTHERN CALIFORNIA
O: 05MAY2026 15:22:26 38.2N 122.2W MD=2.6 EMSC NORTHERN CALIFORNIA
O: 05MAY2026 23:23:20 37.6N 122.5W MD=2.4 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 05MAY2026 14:57:00 38.0N 122.3W MD=2.5 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 05MAY2026 14:57:00 38.0S 122.3W MB=2.5 NEIC NORTHERN CALIFORNIA
EMSC reported an earthquake of M 4.9 in Pakistan was felt with intensity up to IV in the area(s) of Pakistan in Khanpur.
O: 06MAY2026 04:06:08 29.9N 70.1E MB=4.9 EMSC PAKISTAN
EMSC reported an earthquake of M 4.9 in the Iran-Iraq border region was felt with intensity up to IV in the area(s) of the Iran-Iraq border region in Iran at Qasr-e Shirin, Ilam, Kermanshah, and in Iraq at Najaf, Baghdad, At Tarmiyah, Al Miqdadiyah, Khanaqin.
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.
This event may be related to stresses on the earth related current hostilities
and explosions in the area of Iran and Iraq. This last earthquake within about
200 km of this epicenter with M>=4.9 occurred on June 30, 2024 with M 4.9, the last of
larger magnitude was an M M 5.1 on March 16, 2023. At the time this summary noted:
"In addition to seismic enhancement near the 103 degree distance from the
Kermadec Islands, the 144 degree distance also showed seismic promotion today.
Earthquake of M 5.2 occurred at this distance from the Kermadec Islands in Iran and
Iraq at 144-145 degrees from the Kermadec epicenter.
NEIC reported the event of M 5.1 in Iraq was felt with intensity II-III in the area(s) of Iraq in Sulaymaniyah (IV), Irbil and in Iran at Dezh Shahpur, Kordestan (IV), Pawa, Kerman, Javanrud, Islamabad." (March 16, 2023)
This epicenter is at the fifth node (72 degrees) from Honshu, Japan and Malaysia
and may have been promoted by energy from those sources.
O: 05MAY2026 20:53:21 34.2N 45.8E MB=4.9 EMSC IRAN-IRAQ BORDER REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TROPICAL STORM HAGUPIT
---- ------- ---------- -------- ----- ------ ------- ---------------
TS HAGUPIT 2026-05-06 00:00 UT 7.4N 146.9E 45 kts North Pacific
Tropical Storm Hagupit formed today in north Pacific area with winds up to 45 kts south of Guam. This storm is moving to the WNW with winds up to 45 kts. It is unlikely to trigger seismicity in Guam but may promote some in the Caroline Islands. The antipode is at 7S 34W in the South Atlantic and is not a seismic area.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
1130 0419 0424 0430 C1.2 (May 5, 2026) 8.3E-04
Myanmar M 3.9 04:22 UT
Banda Sea M 3.7 04:22 UT
1140 0504 0512 0520 C1.3 (May 5, 2026) 1.2E-03
Assam, India M 3.2 05:12 UT < 3.3 05:13 UT
1160 0521 0527 0537 C6.0 (May 5, 2026) 4.2E-03
1180 0818 0827 0830 C1.1 (May 5, 2026) 1.1E-03
New Zealand M 3.5 08:22 UT
1240 1409 1412 1415 C1.8 (May 5, 2026) 7.1E-04
1250 1459 1509 1512 C1.2 (May 5, 2026) 9.4E-04
Mid-Indian Ridge M 5.1 15:09 UT
San Francisco, California M 2.5 14:57 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 6 active May 7-8. Solar M-flare chance: 25% X-class: 1% proton storm: 1%
AP Indicies: global: 12, high: 15, mid-latitude: 11, time of max AP: 02:00 UT; Max AP: 5 Global Kp 5.00 0000-0300, May 5; Sunspot Number: 119; Radio Flux: 128
May 5, 2026
Notable earthquakes and events:
The Planetary K-index reached Kp 6.33 late on UT May 4, 2026 and remained
active through the remainder of the day into early May 5. This is the
first time the Planetary K- value has reached levels of G-2 storminess
in the past month. The only time it reached a value equal or higher than
this in the current quarter was on April 3, 2026 when the Kp was 6.67
late in the UT day. Today's geomagnetic storm reached a peak near 00:00 UT
on May 5 with a strong geomagnetic excursion on the GOES-19 magnetometer peaking
around 06:00 UT on May 5. Areas at local solar noon at the time of commencement
of this storm are near the International Date Line (IDL) at 180 E/W longitude.
These are the areas most likely to see strong seismic triggering with this
storm and include the Tonga-Fiji-New Zealand area in the South and the Aleutians, Alaska on the
north. A strong geomagnetic excursion in the earth's field also occurred around 06:21 UT
on May 4. This was strong enough that an arcjet correction to the orbit
of GOES-19 was necessary to compensate for orbital fluctuations.
A strong M 5.8-6.0 earthquake accompanied the geomagnetic storm today
in the area off north Island New Zealand today. This area was at local
solar noon conditions at the peak of the geomagnetic storm and was probably
promoted by effects from that storm. NEIC reported the mainshock was felt
with intensity III in Naikato and Bay of Plenty, New Zealand at Tairua, Coromandel, Whitianga, Tauranga, Te Puke, Whangamata, Pauanui, Thames and II in Waiheke, and Manukau, Auckland.
GeoNet reported the following data for this activity:
O: 05MAY2026 08:00:41 36.6S 177.2E MB=6.0 GEONET 1958 people reported feeling this earthquake with 1436 at weak intensity and 472 with light shaking and 44 with moderate intensity 4 with strong, 0 with severe and 2 with extreme intensity.
O: 05MAY2026 08:05:39 36.9S 177.1E ML=4.2 GEONET 1083 people reported feeling this earthquake with 780 at weak intensity and 277 with light shaking and 22 with moderate intensity 3 with strong, 0 with severe and 1 with extreme intensity.
The mainshock was followed by a number of moderate sized aftershock including those of M 4.5 and 4.9. The last earthquake within about 200 km of this epicenter in New Zealand
with M>=6 occurred as an M 6.5 on December 15, 1994. An M 6.0 hit about 250 km southeast of today's
epicenter on April 5, 2021 - an aftershock of an M 7.3 on March 4, 2021.
At the time this summary noted:
"... Kermadec Islands (M 8.1 on the same day - March 4, 2021) follows an M 7.3 off North Island, New Zealand which occurred earlier in
the day. NEIC reported this event was felt with maximum intensity VII in Gisborne at Tokomaru Bay; VI in Te Karaka, Opotiki; V in Ruatoria, Gisborne, the Bay of Plenty, IV in Patutahi, Whakatane, Matata and Kawerau, Bay of Plenty. and was summarized in the previous issue of this summary.
The earthquake of M 7.1-7.3 shook the region of North Island, New Zealand today.
GEONET reported this earthquake was felt with moderate to strong intensity in North Island, New Zealand with 13854 reporte of which 3874 reported weak shaking; 5016, light, 4158 moderate, 756 strong, 46 Severe and 12 extreme intensity.
No major damage was reported with this earthquake, but a minor tsunami may occur
in the region of North Island. The last earthquake within about 250 km of
today's epicenter within about 250 km of this epicenter with M>=7.3 occurred
more than 30 years ago. The only earthquake recorded in this region north
of North Islands in history of larger magnitude was an M 7.9 under North
Island on February 2, 1931. This was the Hawke's Bay earthquake and caused
a great deal of damage in North Island especially near Napier.
Today's earthquake occurred within about an hour of local solar midnight and
may have been promoted by strong tidal stresses with the full moon which
maximize near this hour." (March 4, 2021)
Today's epicenter is located at the sixth node (60 degrees) from the Molucca Sea and at the
fifth node (72 degrees) from Malaysia and may have been promoted by energy
from those sources.
O: 05MAY2026 08:00:43 36.8S 177.3E ML=5.8 NEIC NORTH ISLAND, NEW ZEALAND
O: 05MAY2026 08:00:41 36.6S 177.2E ML=6.0 GEONET NORTH ISLAND, NEW ZEALAND
O: 05MAY2026 08:43:45 36.6S 177.3E MW=4.9 EMSC OFF E. COAST OF N. ISLAND, N.Z
O: 05MAY2026 08:00:48 36.7S 177.2E Mw=5.8 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:07:18 36.7S 177.1E ML=4.2 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:22:28 36.7S 177.2E ML=3.5 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:28:26 36.7S 176.6E ML=3.2 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:38:59 36.7S 177.3E ML=3.3 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:49:37 36.7S 177.1E ML=4.3 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 06:53:51 36.8S 177.1E ML=3.2 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 08:05:39 36.9S 177.1E ML=4.2 EMSC OFF E. COAST OF N. ISLAND, N.Z.
O: 05MAY2026 06:42:10 36.7S 177.2E ML=4.2 EMSC OFF E. COAST OF N. ISLAND, N.Z
An earthquake of M 5.8 also occurred today in the Sumba region of Indonesia.
NEIC reported it was likely felt in the Tambolaka area of Indonesia.
This even occurred near local solar noon and was probably promoted by
the strong geomagnetic storm of early May 6. The last earthquake of M>=5.8
within about 200 km of today's epicenter occurred as an M 6.4 on January 22, 2019.
At the time this summary noted in this regard:
"A strong earthquake of M 6.4 hit south of Sumbawa, Indonesia today. It was
reported felt with intensity II in Mataram, Indonesia by NEIC.
This event occurred within about an hour of local solar noon, a prime time
for high tidal stresses which can help promote seismicity. The epicenter was
nearly sub-solar at the time of the earthquake.
...
The mainshock of M 6.4 was preceded by an M 6.0 several hours earlier which was felt with intensity II in Bali, Indonesia.
The M 6.4 is the strongest earthquake within about 200 km of today's epicenter
in at least 30 years. The most recent nearby event was an M 6.6 about 250 km to the northwest
of this on November 8, 2009." (January 21, 2019)
O: 05MAY2026 06:44:51 10.1S 119.3E ML=5.8 NEIC SUMBA, INDONESIA
O: 05MAY2026 06:44:54 10.1S 119.3E MW=5.8 EMSC SUMBA REGION, INDONESIA
O: 05MAY2026 04:57:57 10.2S 119.3E ML=4.2 EMSC SUMBA REGION, INDONESIA
The strongest earthquake in the U.S. or Canada today was an M 4.5 in the Tonopah area
of Nevada. This is not part of the recent moderate earthquakes in western
Nevada and not near the Testing grounds north of Las Vegas and is a new
epicenter for the Nevada during this active period. NEIC reported the mainshock
which was followed by a number of smaller aftershocks was felt in Nevada at Tonopah and possible in
Carson City and Henderson with II-III intensity. This epicenter was near
local solar noon when the geomagnetic storm commenced today and was likely
promoted by energy from that source (see above).
The last earthquake with M>=4.5 within about 100 km of this epicenter in Nevada
occurred on January 15, 1993 with M 4.5. The only comparable event since
then was an M 4.5 about 150 km north of today's epicenter on July 18, 2023. At the
time this summary noted:
"A moderate earthquake of M 4.4-4.6 also occurred today 6 in north-central Nevada. NEIC reported it was felt with intensity IV in Eureka and II-III in Austin, Tonopah, Wellington, Glenbrook, Colfax (California) and Henderson.
In the past 35 years earthquakes of M 4.5-4.6 have been located within about 100 km of today's epicenter
on September 10, 2019 and January 15, 1993. When the event of M 4.6 occurred on
September 10, 2019 this summary noted:
"The strongest earthquake in the U.S. or Canada outside Alaska today was an M 4.6 in central Nevada. NEIC reported it was felt with maximum intensity V in Austin, Nevada and II-III in Fallon, Elko, Carson City and Las Vegas, Nevada.
No major damage was reported. This is the first such earthquake within about 200 km
of this epicenter in at least 30 years. An M 4.7 hit about 250 km northeast of
this on November 23, 2003." (September 10, 2019)
Today's M 4.6 occurred within minutes of local solar midnight and may
have been promoted by tidal stresses which maximize near this hour." (July 19, 2023)
This epicenter is at the fifth node (72 degrees) from Honshu, Japan
and may have been promoted by energy from that source. It is also at the
seventh node (51.4 degrees) from the North Geomagnetic Pole.
O: 05MAY2026 02:39:52 38.4N 116.5W ML=4.5 NEIC TONOPAH, NEVADA
O: 05MAY2026 02:39:54 38.5N 116.4W Mw=4.5 EMSC NEVADA
O: 05MAY2026 06:41:42 38.2N 116.6W ML=2.2 EMSC NEVADA
O: 05MAY2026 02:43:09 38.4N 116.5W ML=3.0 EMSC NEVADA
O: 05MAY2026 02:49:11 38.4N 116.5W ML=3.0 EMSC NEVADA
O: 05MAY2026 03:17:05 38.4N 116.5W ML=2.1 EMSC NEVADA
O: 05MAY2026 06:12:58 38.4N 116.8W ML=2.1 EMSC NEVADA
O: 05MAY2026 02:47:42 38.5N 116.5W ML=2.8 EMSC NEVADA
O: 05MAY2026 02:50:38 38.5N 116.5W ML=3.4 EMSC NEVADA
O: 05MAY2026 02:59:29 38.5N 116.4W ML=2.3 EMSC NEVADA
O: 05MAY2026 03:39:47 38.5N 116.5W ML=2.7 EMSC NEVADA
O: 05MAY2026 03:53:52 38.5N 116.4W ML=2.1 EMSC NEVADA
O: 05MAY2026 04:13:45 38.5N 116.5W ML=2.9 EMSC NEVADA
O: 05MAY2026 06:20:19 38.5N 116.5W ML=2.2 EMSC NEVADA
O: 05MAY2026 06:40:43 38.6N 116.4W ML=2.6 EMSC NEVADA
A moderately large earthquake of M 5.7 has occurred in central Mexico in the
State of Oaxaca. NEIC reported intensity IV in Oaxaca, Chilpancingo, Guerrero; III in San Agustin de las Juntas, Atzompa, Tlacoachistlahuaca, Buenavista, Cuautla, Santa Lucia del Camino, Montecillo, Huayapam. EMSC reported it was felt in Mexico at Puerto Escondido, Tuncingo, Fraccionamiento Lomas de Ahuatlan, Acxotla del Rio, Texcalyacac, Coyoacan, Benito Juarez, Col Bosques de las Lomas, Polanco and Plan de Ayala.
The occurrence of this earthquake at this time is consistent with tidal triggering
with the full moon of April 1 and the geomagnetic excursion at 06:07-06:21 UT on May 4, 2026 (see above).
as it was at local solar midnight when that anomaly occurred.
This east earthquake in Oaxaca/Guerrero, Mexico with M>=5.7 within about 200 km of this
epicenter was an M 5.7 on February 8, 2026 about 150 km to the southeast of today's
epicenter and an M 6.5 on January 2, 2026 about 150 km northwest of today's epicenter.
At the time this summary noted:
"The strongest earthquake in the world today was an M 5.7 event in Oaxaca,
Mexico. NEIC reported it was felt with intensity IV in Oaxaca t Puerto Escondido, Santa Lucia del Camino and III in Oaxaca at Oaxaca, Zadani, Pochutla, Pinotepa Nacional and Atzompa and in Veracruz at Playa Viente, Tierra Blanca, and Cordoba.
EMSC reported it was strongly felt in Oaxaca, Mexico in Birsas de Zicatela, San Bernardino, Colonia Libertad, Puerto Escondido, La Barra de Colotepec, San Miguel Figueroa, Crucecita, Santa Ana del Valle, Santa Maria del Tule, Oaxaca, Chilpancingo, Veracruz, Santiago Momoxpan, Huamantla, Apizaco, Ejido la Venta Cuautlalpan, Xochimilco, Texcoco de Mora, Coyoaca, Venustiano Carranza, Cuauhtemoc, Polanco, Gustavo Adolfo Madero, Mesa de los Leones, Nicolas R. Casillas, San Jose del Valle.
This earthquake occurred near local solar noon and was probably promoted
by strong geomagnetic changes which maximize near this hour.
This is the strongest earthquake in Oaxaca, Mexico within about 200 km of this
epicenter since an M 5.8 on August 2, 2025. At the time this summary noted
in this regard:
"A moderately strong earthquake of M 5.8 also hit the area of Chiapas and Oaxaca, Mexico today. NEIC reported intensity IV in Oaxaca at Cuilapam, Etla, wit III in Huajuapan, Mexico City, Naucalpan, Concordia, and II in Morelos, Cuernavac, Tlalnepantla.
EMSC reported strong Shaking in Oaxaca, Mexico at Santa Ana del Valle, Brisas de Zicatela, San Luis Acatlan, San Bernardino Tlaxcalancingo, San Matias, Ciudad de Huitzuco, Ixtapaluca, Fraccionamiento Lomas de Ahuarlan, Coyoacan, Alvaro Obregon, Santa Rosa, and Azcapotzalco and Mexico City.
A foreshock earlier in the day of M 4.3 was also felt in Oaxaca, Mexico.
This epicenter is located near the fourth node (90 degrees) from Kamchatka
and at the sixth node (60 degrees) from the M 7.3 in the Alaska Peninsula or July 16
and may have been promoted by energy from those sources.
This event occurred at the beginning of the strongest solar flare in several
days - a C3.1 (#950). It may have been promoted by SFE from that flare." (August 2, 2025)
This epicenter is at 102 degrees from Honshu, Japan and may have been promoted
by energy from that source." (February 9, 2026)
Today's epicenter is at 101 degrees from Honshu, Japan and may have been
promoted by energy from that source.
O: 04MAY2026 15:19:26 16.6N 98.0W ML=5.7 EMSC OAXACA, MEXICO
O: 04MAY2026 15:19:25 16.6N 98.0W MW=5.7 EMSC OAXACA, MEXICO
O: 04MAY2026 16:33:09 16.0N 98.2W ML=4.0 EMSC OFFSHORE OAXACA, MEXICO
O: 04MAY2026 14:24:49 16.3N 98.3W ML=4.0 EMSC OAXACA, MEXICO
O: 04MAY2026 15:29:59 16.3N 98.3W ML=4.1 EMSC OAXACA, MEXICO
Several other seismic areas are also near 11.7 degrees north latitude.
These include the area of Nicaragua and Costa Rica in Central America.
An earthquake in Costa Rica of M 4.7 occurred at 11 North latitude today
while a series of light earthquakes occurred in Nicaragua yesterday
and today with maximum magnitude M 3.5 at 11.3N latitude within minutes of local solar noon.
These may also have been promoted by tidal stresses at their sub-solar latitudes.
O: 04MAY2026 13:50:40 11.6N 87.0W ML=4.5 NEIC NICARAGUA
O: 04MAY2026 13:50:44 11.5N 87.0W MB=4.5 EMSC NEAR COAST OF NICARAGUA
O: 03MAY2026 14:55:45 8.4N 83.0W ML=4.0 EMSC COSTA RICA
O: 03MAY2026 17:02:33 11.3N 87.4W ML=3.5 NEIC NICARAGUA
NEIC reported an earthquake of M 2.7 in Michigan was felt with intensity up to II-III in the area(s) of Michigan with IV in Rockwood; III in Carleton, Maybee, Willis, Dundee, Davison, Newport, New Boston, Monroe, La Salle, Belleville, Trenton, Livonia, Temperance, New Hudson, Petersburg, Flat Rock, Ypsilanti, Milan, Lambertville, Lincoln Park, Kalamazoo, Deerfield, Flushing, Clinton, Mancelona, Erie, Ann Arbor, Dearborn, Allen Park, Eaton Rapids, Royal Oak, and in Ohio at Toledo.
EMSC reported a loud booming noise and shaking in Carleton and Rockwood, Michigan.
Local press reported no damage from this earthquake which occurred in northern Monroe County, Michigan.
This is the second earthquake in southern Michigan in the past week.
On April 26, 2026 this summary reported on an M 2.9 northeast of this epicenter
in Michigan as:
"NEIC reported an earthquake of M 2.9 in Michigan was felt with intensity up to II-III in the area(s) of Michigan with III in Detroit, South Rockwood, Grosse Ile, Carleton, Rockwood, Trenton, Erie, Flat Rock, Monroe, Detroit. It was also felt in large portions of Southern Ontario, Canada.
EMSC reported shaking and noise in Michigan rolling across Lake Erie at Rockwood, Grosse Ile, and Monroe.
The last earthquake within about 150 km of this epicenter in Michigan with
M>=2.9 occurred as an M 3.2 on August 21, 2020. At the time this summary noted:
"An unusual earthquake of M 3.2 was widely felt in the area south of Detroit, Michigan today. NEIC reported maximum intensit IV in Michigan at Monroe, Luna Pier, South Rockwood and II-III in Newport, La Salle, Carleeton, Rockwood, Erie, Flat Rock. The earthquake was felt with light intensity as far as Ohio, Pennsylvania, Wisconsin, Illinois, New Jersey, New York, Tennessee, North Carolina, Massachusetts, Georgia, Connectict and Missouri among other states in the eastern U.S.
No major damage was reported. The last earthquake in the Detroit area occurred
as an M 3.4 on April 20, 2018. The largest regional earthquake in the past
30 years was an M 4.2 on May 2, 2015. An M 2.0 also occurred when a meteor hit the earth near Detroit on January 16, 2018. Other recent
quakes occurred as an M 4.0 near Kalamazoo on May 2, 2015. Today's earthquake
did not affect operations at the area's two nuclear power plant.
When the M 4.2 occurred in May, 2015 this summary noted:
"The last earthquake within about 200 km of this epicenter with M>=4.2 occurred
on August 10, 1947 with M 4.7. Other recent earthquakes in the area occurred
on February 4, 1883 and February 4, 1833 (may be an error in the year).
The earthquake in 1883 was felt in northern Indiana and southern Michigan in Kalamazoo, Michigan.
Windows were cracked and chimneys damaged in Kalamazoo. It was felt as far as
St. Louis, Missouri and in Bloomington, Illinois. The earthquake in 1947 was also
located near the epicenter of today's event. It was felt through southern Michigan where
damage was reported. It was also felt with intensity up to VI in Illinois, Michigan, Indiana
and Wisconsin. Damage included cracked plaster, with windows and items thrown down from store shelves." (May 3, 2015, August 21, 2020, April 26, 2026)
Today's earthquake in Michigan occurred near local solar noon as the strong
geomagnetic storm (see above) was commencing. It was probably promoted by
energy associated with that storm.
This epicenter is at 103 degrees from Tonga and at the fourth node (90 degrees)
from Honshu, Japan and may have been promoted by energy from those sources.
O: 04MAY2026 21:32:00 42.1N 83.5W ML=2.7 NEIC MICHIGAN
O: 04MAY2026 21:32:00 42.1N 83.5W ML=2.7 EMSC MICHIGAN
NEIC reported an earthquake of M 4.7 in the Fox Islands, Alaska was felt with intensity up to II-III in the area(s) of Akutan, Alaska.
O: 05MAY2026 02:38:47 53.6N 165.6W ML=4.7 NEIC FOX ISLANDS, ALASKA
O: 04MAY2026 17:29:00 53.7N 164.1W MB=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
O: 05MAY2026 02:38:47 53.5N 165.5W Mw=4.7 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
NEIC reported an earthquake of M 4.2 in Croatia was felt with intensity up to II-III in the area(s) of Croatia with V in Serbia and Montenegro at Bezdan; IV in Sombor Vojvodina and III in Backa Topola and in Croatia at Visnjevac Osijek-Baranga and Osijek. It was also lightly felt in Hungary at Bonyhad and Szkszard, Tolna.
EMSC reported strong shaking in Croatia at Batina, Zmajevac, Grabovac, Popovac, Karanac, Knezevo, Beli Manastir among others; in Hungary at Davod, in Serbia at Stanisic, Sombor, Apatin, Backi Breg among others.
This epicenter is at 101 degrees from the Molucca Sea and the fourth node (90 degrees)
from Malaysia and may have been promoted by energy from those sources.
O: 05MAY2026 00:35:51 45.8N 18.9E ML=4.2 NEIC CROATIA
O: 05MAY2026 00:35:51 45.8N 18.9E MB=4.2 EMSC CROATIA
NEIC reported an earthquake of M 4.5 in South Australia was felt with intensity up to II-III in the area(s) of South Australia in Yulara.
This epicenter is at the tenth node (36 degrees) from Malaysia, Vanuatu and the South
Geomagnetic Pole and may have been promoted by constructive energy interference
from those sources.
O: 05MAY2026 00:08:11 25.9S 130.9E ML=4.5 NEIC SOUTH AUSTRALIA
O: 05MAY2026 00:16:51 26.0S 130.7E MB=4.5 EMSC SOUTH AUSTRALIA
NEIC reported an earthquake of M 5.2 in northern Honshu, Japan was felt with intensity up to II-III in the area(s) of northern Honshu, Japan at Misawa, Aomori.
O: 04MAY2026 23:54:06 40.0N 143.0E ML=5.2 NEIC OFF NORTHEAST HONSHU, JAPAN
O: 04MAY2026 23:54:05 40.0N 143.0E MW=5.2 EMSC OFF EAST COAST OF HONSHU,
O: 04MAY2026 21:42:08 39.9N 143.2E mb=4.8 EMSC OFF EAST COAST OF HONSHU,
NEIC reported an earthquake of M 4.5 in the Rat Islands, Aleutians, Alaska was felt with intensity up to II-III in the area(s) of the Rat Islands, Aleutians, Alaska was likely felt in Attu Station.
O: 04MAY2026 19:14:27 52.1N 176.3E ML=4.5 NEIC RAT ISLANDS, ALASKA
O: 04MAY2026 13:09:28 52.0N 176.2E ML=3.9 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 05MAY2026 01:57:41 52.0N 176.2E ML=4.0 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 04MAY2026 19:14:26 52.2N 176.3E mb=4.5 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 04MAY2026 21:11:27 52.2N 176.4E mb=4.2 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
NEIC reported minor earthquakes of M 2.5 in Southern Texas continued to be felt with intensity up to II-III in the area(s) of southern Texas with light shaking as far as Austiin.
O: 04MAY2026 18:40:54 28.9N 99.0W ML=2.5 NEIC SOUTHERN TEXAS
O: 04MAY2026 09:04:13 28.8N 99.0W ML=2.2 EMSC SOUTHERN TEXAS
O: 04MAY2026 09:59:38 28.9N 99.1W ML=2.6 EMSC SOUTHERN TEXAS
O: 04MAY2026 18:40:54 28.9N 99.1W ML=2.5 EMSC SOUTHERN TEXAS
O: 04MAY2026 19:58:47 28.9N 99.1W ML=2.1 EMSC SOUTHERN TEXAS
EMSC reported an earthquake of M 4.3 in Crete, Greece was felt with intensity up to IV in the area(s) of Crete, Greece at Ferma.
O: 05MAY2026 07:21:13 34.9N 26.0E ML=4.3 EMSC CRETE, GREECE
EMSC reported an earthquake of M in was felt with intensity up to IV in the area(s) of
O: 04MAY2026 09:06:21 29.5S 68.1W ML=4.0 EMSC LA RIOJA, ARGENTINA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
No tropical cyclones are currently active
A tropical cyclone may be forming in the north Pacific area. This storm is currently located at 8N 149E and moving to the WNW with winds up to 23 kts. It is tracking towards Guam where it may arrive in several days and help promote regional seismicity at that time.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
920 0113 0133 0220 M1.8 (May 4, 2026) 1.4E-02
Central California M 2.1 01:22 UT
Samar, Philippines M 6.0 06:09 UT
Kamchatka M 4.4 01:31 UT
950 1039 1051 1103 C1.2 (May 4, 2026) 1.7E-03
960 1133 1139 1142 C1.5 (May 4, 2026) 7.9E-04
980 2200 2206 2214 C1.5 (May 4, 2026) 1.3E-03
Java M 4.2 22:14 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 6 active May 5 and May 7. Solar M-flare chance: 30% X-class: 5% proton storm: 5%
AP Indicies: global: 26, high: 26, mid-latitude: 16, time of max AP: 20:00 UT; Max AP: 6 Global Kp 6.33 1800-2100, May 4; Sunspot Number: 143; Radio Flux: 138
May 4, 2026
Notable earthquakes and events:
UPDATE:
A moderately large earthquake of M 5.7 has occurred in central Mexico in the
State of Oaxaca. EMSC reported it was felt in Mexico at Puerto Escondido, Tuncingo, Fraccionamiento Lomas de Ahuatlan, Acxotla del Rio, Texcalyacac, Coyoacan, Benito Juarez, Col Bosques de las Lomas, Polanco and Plan de Ayala.
The occurrence of this earthquake at this time is consistent with tidal triggering
with the full moon of April 1 and the geomagnetic excursion at 06:07 UT (see below).
as it was at local solar midnight when that anomaly occurred.
This epicenter is at 101 degrees from Honshu, Japan and may have been
promoted by energy from that source.
O: 04MAY2026 15:19:26 16.6N 98.0W ML=5.7 EMSC OAXACA, MEXICO
A strong eruption of Mayon Volcano in Central Philippines occurred today. This eruption
south of Manila, Philippines cause airspace to be restricted near Manila and thousands to be
evacuated in the region of the volcano. Lava deposits collapsed and ashfall caused
zero visibility in Camalig town near the volcano's foothills. The area of the Philippines
had been considered likely to see enhanced activity at this time due to
tidal and geomagnetic effects as this summary noted on May 1, 2026:
"A moderate geomagnetic storm occurred late on UT April 30, 2026. This storm reached its maximum atourn 08:00 UT on May 1, 2026 with high
latitude K 5 and planetary KP in the 4's most of late April 30 and early
May 1. Strong excursions in the geomagnetic field strength occurred near 04:30 UT and again near 08:00 UT
on May 1 as shown on both GOES 19 and GOES 18 magnetometers. These would have been consistent with enhanced seismic triggering
in western U.S. and the western rim of fire along the western Pacific in
Asia. This summary had expected this type of activity at this time in the
previous issue as:
"Several sunspot groups should be returning after rotation in the next several
days. In the last rotation these caused moderately strong flares and subsequent
geomagnetic storms. In conjunction with the full moon on May 1, 2026 this
will probably break the earth out of the current seismic doldrums and
moderate to strong earthquakes are considered by this summary as likely in
the next five days. The most likely locations for such events is in central
and western South America and in eastern Asia including Western Indonesia
and the Philippines." (April 30, 2026, May 1, 2026)
The full moon arrived on May 1, 2026 at 17:23 UT. Longitudes which are sub-solar (local solar noon) are near 84 West longitude while those at local solar midnight are centered near 96 East longitude. In the west these include area of Central and northwestern South America and eastern U.S. and in the east areas of western Indonesia, Myanmar, Tajikistan and western China. These areas are most likely to see tidal triggering with this full moon. A moderately large to large tidally triggered earthquake is considered moderately likely with this full moon in the period April 30-May 5, 2026.
Mayon Volcano is located at 13.2N 123.7E in Central Bikol, Luzon.
Other moderately large to large earthquakes in the past two days near this
longitude occurred as an M 5.7 in south-central Honshu, Japan and an M 5.9-6.1
north of Taiwan. This activity is most likely related to tidal effects from the full moon of
May 1 (see above).
A strong earthquake of M 6.0 also occurred today in the Samar region of
central Philippines. NEIC reported intensity VI in the Eastern Visayas, Philippines at Tutubigan; V in Pawing, IV in San Antonio, Consolacion, Balaquid, Naghalin; III in Pastrana, Baybay and Kilim.
Only minor damage was reported in the epicentral area. EMSC reported it was felt with long duration in the Philippines at Tacloban, Baybay, General Luna, and Palampas. This was the strongest earthquake in the world in
the past 24 hours. It is located about 250 km south of Mount Mayon
and may have been promoted by stress redistribution following the eruption
of that volcano. The last earthquake in Samar, Philippines within about
200 km of today's epicenter occurred on September 30, 2025 with M 6.9.
At the time this summary noted:
"A major earthquake of M 6.9-7.1 has hit central Philippines near Samar and Leyte. Local News
outlets including the Manila Bulletin indicated that many people were killed
in this earthquake. At this writing at least 69 deaths and hundreds of injuries have been confirmed
from the earthquake with several collapsed bridges and other structures. Many residents spent the night outdoors.
In some areas water supplies were note available. Many of these were attending a basketball game at the San Remigio Sports Complex and Recreation Center some by falling debris. Initial
details are limited as access routes to and from the earthquake area are
blocked by destroyed infrastructure and landslides. A State of Calamity has been
declared for the area. Major damage occurred to over 20 structures including
malls, churches, schools, bridges and sommercial buildings. The internet shows a number
of views of the earthquake as and after it occurred. PTWC issued a bulletin declaring no significant tsunami
threat was likely but that sea level fluctuations and strong dangerous currents
were possible. NEIC reported the quake was felt near the epicenter with
intensity IX (much damage) with reports of V shaking in Bicol, Philippines from
Basud, Bulan, Burabod, Legazpi, Maslog; IV in Mariroc, Libon, and II-III in Malabog, Nabua and Baao.
EMSC reported strong shaking in Leyte at Masarayo, Liloan, Apas, Consolacion, Tacloban, Tolosa, Lapu-Lapu, Cebu City, San Roque, Baugo, Calatrava, Adlaon, Gabi, Dapitan, Victorias, Minglanilla, Barili, Talisay, Pontevedra, Roxas City, Baclayon, Tangnan, and many others.
PHIVOLCS reported intensity VII in Daanbantayan, City of Bogo, Medellin, San Remigio and Tabueland, Ceub and in the City of Cebu with IV in the City of Masbate, Masbate, Murcia, Negros Occidental, Bantayan, Borbon Catmon and Sogod, Cebu with V in Masbate, Negros Occidental, Bohol, Cebu, Biliran, Leyte, Ormoc City and the City of Tacloban and IV in Albay, Masbate, Sorsogon Capiz, Negros Occidental, Bohol, Eastern Samar, Northern Samar, northern Leyte and Zamboanga del Norte among others.
There were power blackouts within about 200 km of this epicenter which continued for hours but are mostly restored at this writing.
The last earthquake of M>=6.9 within about 200 km of this epicenter in Indonesia
occurred as an M 7.1 on October 15, 2013 about 200 km southwest of today's epicenter.
It is particularly interesting that that event occurred during a strong
geomagnetic storm and following the passage of a strong typhoon over
the epicenter (Both mirroring the current conditions). At the time this summary noted:
"A major earthquake of M 7.0-7.2 hit the region of Mindanao and the islands
of central Philippines today. This quake caused buildings to collapse, cracked
roads and toppled the bell tower of the Philippine's oldest church. At least
32 people were confirmed killed in early reports. The quake sent people
into the streets in panic. It occurred on a national holiday which probably
saved many lives. The epicenter was under land and no tsunami was observed
or expected. Deaths were reported in Bohol, Cebu, where a fishing port collapsed;
in a market in Mandaue where a market roof collapsed and elsewhere when
falling materials hit many. The number of injured was in the hundreds.
Historic churches suffered the most damage. These included the bell tower in he country's
oldest church - the Basilica of the Holy Child in Cebu. A 17th Century
church in Loboc, southwest of Loboc crumbled to pieces with nearly half
reduced to rubble. Power and telephone service was out in many areas. This
earthquake had been expected at this time. As repeated in this summary
yesterday, the area had been put under seismic watch with the possibility
of a strong quake for the period October 12-16 when Tropical Storm Nari
passed over the region on October 11. That watch had read as follows:
"TS Nari (TD 24W) continued today west of the central Philippines with winds up to 110 kts.
A seismic watch is being called for the area of the central and northern Philippines
and Taiwan for the next five days. Meteorologically triggered earthquakes
are possible in the area during this time. One of these may be moderately
strong." (October 11-13, 2013)
...
This is the strongest earthquake within 200 km of this epicenter in at least
25 years. The last earthquake of larger or similar magnitude in this zone
occurred on May 13, 1897 with M 7.9. An earthquake of M 7.0-7.6 hit about 300
km east of this last year on August 31, 2012.
...
This earthquake may have been immediately triggered by a strong geomagnetic
storm which began mid-day (UT) - around midnight local Philippine time - a prime time for SFE effects on seismicity.
A C7.4 solar flare began about an hour before this earthquake and was
still in progress when the mainshock occurred and may have also promoted
this event's timing." (October 15, 2013)
Like the event of October 15, 2013, today's event in the Philippines also
occurred about an hour after a strong solar flare." (September 30, 2025)
This earthquake in Samar, Philippines (and the eruption of Mount Mayon) occurred when the sun was directly
overhead at noontime in Samar - that is the epicenter was almost exactly
sub-solar at the time of the earthquake. Vertical tidal stresses from the sun are
maximized at this time and may have helped promote today's event.
The sub-solar latitude on May 4 is 23.5/2 = 11.7 degrees north, exactly
the longitude of the Samar earthquake. It is curious that the strongest
earthquake in Samar in the past 31 years occurred on May 5, 1995 with M 7.1 -
also nearly exactly sub-solar. That event occurred within minutes of local
solar noon when the epicenter was exactly sub-solar. A similar event of M 6.4
occurred south of that in Samar on May 8, 1995. These were aftershocks
of an M 7.0 which hit on April 21, 1995. One of the strongest volcanic
eruptions in the 20th century occurred in early June, 1991 at Pinatubo,
Philippines. The ash cloud from that eruption was shown to have cooled
the overall earth temperature by about 1 degree F over the next several years.
The earthquake in Samar, Philippines today followed an M1.8 solar flare which
occurred while this area was near local solar noon. This is the strongest solar flare
since #8100 and #8000 on April 24, 2026 of class X2.4 and X2.5.
Following are the parameters from SWPC for this flare:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0113 0133 0220 M1.8 (May 4, 2026) 1.4E-02
Central California M 2.1 01:22 UT
Samar, Philippines M 6.0 06:09 UT
Kamchatka M 4.4 01:31 UT
A strong variation in geomagnetic field strength occurred as recorded on the GOES-18
magnetometer at 06:10 UT today. This required a orbital arcjet correction
at the same time. This geomagnetic field excursion occurred at the
same time as the M 6.0 in the area of Samar, Philippines (at 06:10 UT).
O: 04MAY2026 06:09:50 11.7N 125.4E ML=6.0 NEIC SAMAR, PHILIPPINES
Several other seismic areas are also near 11.7 degrees north latitude.
These include the area of Nicaragua and Costa Rica in Central America.
An earthquake in Nicaragua of M 4.7 occurred at 11 N latitude today
while a series of light earthquakes occurred in Nicaragua yesterday
and today with maximum magnitude M 3.5 at 11.3N latitude within minutes of local solar noon.
These may also have been promoted by tidal stresses at their sub-solar latitudes.
O: 04MAY2026 13:50:47 11.7N 86.8W ML=4.6 EMSC NICARAGUA
O: 03MAY2026 17:02:33 11.3N 87.4W ML=3.5 NEIC NICARAGUA
The solar flare which peaked at 0133 UT today was also accompanied by
an M 4.6 in Kamchatka. At the time Kamchatka was within minutes of local
solar noon and may have been promoted by SFE from that solar flare.
(see above).
O: 04MAY2026 01:30:53 52.4N 161.5E ML=4.4 EMSC OFF EAST COAST OF KAMCHATKA
NEIC reported more aftershocks of M 3.5 in Western Nevada were felt with intensity up to II-III in the area(s) of Nevada at Silver Springs, Fallon, Dayton, Glenbrook, Reno and in Markleeville, California.
O: 04MAY2026 03:12:04 39.3N 119.1W ML=3.5 NEIC NEVADA
O: 04MAY2026 00:33:51 39.3N 119.0W ML=3.5 NEIC NEVADA
NEIC reported an earthquake of M 4.6 in Unimak Island, Alaska was felt with intensity up to II-III in the area(s) of Unimak Island, Alaska with IV in King Cove and II in False Pass, Alaska.
O: 03MAY2026 19:20:10 54.1N 162.9W ML=4.6 NEIC UNIMAK ISLAND, ALASKA
NEIC reported an earthquake of M 3.3 in Southern California was felt with intensity up to II-III in the area(s) of Southern California with IV in Lebec and III in Frazier Park. It may have been lightly felt in Bakersfield, Santa Barbara and Valencia.
O: 03MAY2026 17:29:19 34.9N 119.0W ML=3.3 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 3.5 in Northern California was felt with intensity up to II-III in the area(s) of Northern California with IV in Covelo and II in Roseville and Sausalito.
O: 03MAY2026 12:52:47 39.8N 123.2W ML=3.5 NEIC NORTHERN CALIFORNIA
EMSC reported an earthquake of M 4.8 in Tajikistan was felt with intensity up to IV in the area(s) of Tajikistan in Islamabad, Pakistan.
O: 04MAY2026 05:55:46 38.7N 73.7E ML=4.8 EMSC TAJIKISTAN
EMSC reported an earthquake of M 4.0 in Coquimbo, Chile was felt with intensity up to IV in the area(s) of Coquimbo, Chile in La Serena.
O: 03MAY2026 20:46:09 29.4S 71.2W ML=4.0 EMSC COQUIMBO, CHILE
EMSC reported an earthquake of M 4.3 in Poland was felt with intensity up to IV in the area(s) of Poland in Jerzmanowa, Grebocice, Glogow, Niechlow, Nowa Sol, Katowice.
O: 03MAY2026 18:38:47 51.6N 16.1E ML=4.3 EMSC POLAND
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 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 when a flare occurred 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 0113 0133 0220 M1.8 (May 4, 2026) 1.4E-02
Central California M 2.1 01:22 UT
Samar, Philippines M 6.0 06:09 UT
Kamchatka M 4.4 01:31 UT
860 0220 0227 0233 C1.5 (May 3, 2026) 1.1E-03
Southern Alaska M 3.1 02:22 UT
870 0333 0341 0347 C1.7 (May 3, 2026) 1.2E-03
Mindanao M 4.0 03:36 UT
880 0656 0708 0715 C3.6 (May 3, 2026) 3.1E-03
Molucca Sea M 4.8 06:57 UT
Bonin Is. M 4.5 07:07 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 4-6. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 8, high: 12, mid-latitude: 8, time of max AP: 18:00 UT; Max AP: 4 Global Kp 3.33 0000-0300, May 3; Sunspot Number: 138; Radio Flux: 143
May 3, 2026
Notable earthquakes and events:
The full moon arrived on May 1, 2026 at 17:23 UT. Longitudes which are sub-solar (local solar noon) are near 84 West longitude while those at local solar midnight are centered near 96 East longitude. In the west these include area of Central and northwestern South America and eastern U.S. and in the east areas of western Indonesia, Myanmar, Tajikistan and western China. These areas are most likely to see tidal triggering with this full moon. A moderately large to large tidally triggered earthquake is considered moderately likely with this full moon in the period April 30-May 5, 2026.
NEIC reported an earthquake of M 3.3 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Covelo.
O: 03MAY2026 00:37:43 39.8N 123.2W ML=3.3 NEIC NORTHERN CALIFORNIA
O: 03MAY2026 00:37:43 39.8N 123.2W ML=3.0 EMSC NORTHERN CALIFORNIA
O: 03MAY2026 00:06:48 39.8N 123.2W MD=2.4 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 2.7 in Western Los Angeles, California was felt with intensity up to II-III in the area(s) of Western Los Angeles, California in Simi Valley, Fillmore and Moorpark.
O: 02MAY2026 21:50:48 34.4N 118.9W ML=2.7 NEIC GREATER LOS ANGELES REGION, CALIFORNIA
O: 02MAY2026 21:50:47 34.4N 118.9W ML=2.6 EMSC GREATER LOS ANGELES AREA, CALI
O: 02MAY2026 19:01:08 34.4N 118.9W ML=2.4 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 4.3 in North Island, New Zealand was felt with intensity up to IV in the area(s) of Wellington at Wellington and Lower Hutt.
EMSC reported it as a sharp quick jolt in Porirua.
GeoNet gave the following data from this earthquake:
O: 02MAY2026 15:15:18 41.1S 174.7E ML=4.1 GEONET 2254 people reported feeling this earthquake near Seddon, New Zealand with 994 at weak intensity and 1078 with light shaking and 176 with moderate intensity 5 with strong, 0 with severe and 1 with extreme intensity.
This earthquake may have been promoted by SFE from solar flare 800 (3.5)
which maximized output within minutes of this event. Data on this flare
from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
800 1511 1521 1531 C3.5 (May 2, 2026) 3.7E-03
Cook Strait M 4.3 15:15 UT
O: 02MAY2026 15:15:18 41.2S 174.9E ML=4.3 NEIC GRENADA NORTH, NEW ZEALAND
O: 02MAY2026 15:15:17 41.1S 174.7E ML=4.0 EMSC COOK STRAIT, NEW ZEALAND
NEIC reported frther aftershocks of M 3.5 in western Nevada today were felt with intensity up to II-III in the area(s) of Nevada at Fallon, Silver Springs and Glenbrook and in Galt, California.
O: 02MAY2026 14:09:35 39.3N 119.1W ML=3.5 NEIC NEVADA
O: 02MAY2026 14:09:35 39.3N 119.1W ML=3.4 EMSC NEVADA
O: 03MAY2026 05:30:33 39.3N 119.1W ML=2.5 EMSC NEVADA
O: 03MAY2026 05:34:38 39.3N 119.0W ML=2.5 EMSC NEVADA
NEIC reported an earthquake of M 4.9 in Tonga was felt with intensity up to II-III in the area(s) of Tonga in Neiafu Vava'u.
This even occurred within minutes of local solar midnight and may have been
promoted by tidal stresses with the full moon of May 1 and/or geomagnetic stresses which maximize near this hour.
O: 02MAY2026 11:30:49 18.2S 175.3W ML=4.9 NEIC TONGA
O: 02MAY2026 11:30:49 18.2S 175.4W MB=4.9 EMSC TONGA
NEIC reported an earthquake of M 2.6 in Greater Los Angeles, California was felt with intensity up to II-III in the area(s) of Greater Los Angeles, California with III in Ontario, Chino, Chino Hills and II in Corona, Riverside, Norco, and Redlands.
O: 02MAY2026 21:26:17 34.2N 117.5W ML=2.4 EMSC SOUTHERN CALIFORNIA
O: 02MAY2026 10:10:46 34.0N 117.6W ML=2.6 NEIC GREATER LOS ANGELES REGION, CALIFORNIA
A moderately strong earthquake occurred today in Central Honshu, Japan with M 5.7. NEIC reported it was felt
with intensity IV in Japan in Nara, Oyodo, Aichi, Nagoya, Anjo, Hyogo, Kobe, Osaka, Kusatsu, Shiga, Kyoto and III in Wakayama, Osakasayama, and Chiryu.
EMSC reported strong shaking in Japan at Kobe, Kyoto, Yoshinogawa, Taketoyo, Nagoya, Okazaki, Gifu-shi, Onomichi, Zama, Kawasaki and Urayasu.
JMA reported this earthquake with M 5.7 with maximum shaking in the area of
Kobe at 5+ on the Japanese Intensity scale. It was felt with intensity 2 in Kyushu and Shikoku in the west
to Tokyo in the East. It is likely this earthquake was promoted by strong
tidal effects with the full moon today (see below with Taiwan quake today). The last shallow focus earthquake in Central or Southern Honshu, Japan with M>=5.7 within about 200 km of today's
epicenter occurred as an M 6.0 on April 1, 2016. An M 7.4 hit the area of
Kobe on September 5, 2004. At the time this summary noted:
"... The strongest events in the past three days
have occurred in western Japan where events of M 7.1, 7.0 and 6.3 injured
at least 43 people and caused minor damage. These are the strongest felt in the
Tonankai epicentral region since 1944 but no deaths have been reported.
Injuries occurred in Osaka Prefecture and in Mie, Aichi, Nara, Kyota, Shiga,
Gifu, Shizuoka, Wakayama and Hyogo prefectures. Tsunamis were associated with
both of the major earthquakes. The Japan Meteorological Agency (JMA) indicated
that these quakes were distinctive in two regards - two earthquakes of M>=7
within such a sort period are unusual in Japan although they have occurred
for example in the September 1-2, 1923 quakes in Tokyo when an M 8.3 was followed
the next day by an M 7.7. The other is that the quakes occurred in an area
where strong quakes have been rare in recent years. The last earthquake of M>7
within 100 km of this epicenter occurred as an M 8.3 on Dec. 7, 1944. In the
larger area (31-37N 135-140E) the last event of M>7 occurred at deep focus
on March 7, 1978 (M 7.6); Jan. 1, 1984 (M:7.3) and Oct. 11, 1993 (M 7.1)." (September 5, 2004) The
Today's earthquake in Honshu, Japan may have been promoted by SFE from
Solar flare 710 (C2.2, one of the larger flares of the day) which maximized
within minutes of the event in Japan. Data on this flare from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
710 0922 0925 0928 C2.2 (May 2, 2026) 8.4E-04
Central Honshu M 5.7 09:28 UT
O: 02MAY2026 09:28:40 34.1N 135.5E ML=5.7 NEIC CENTRAL HONSHU, JAPAN
O: 02MAY2026 09:28:40 34.1N 135.5E MW=5.7 EMSC NEAR S. COAST OF WESTERN
A moderately large M 5.6 earthquake was widely felt on North Island, New Zealand
today. NEIC gave this M 5.1 and reported it was felt WNW of Hicks Bay, New Zealand with III in Whakatane, Bay of Plenty and Gisborne and possibly in Rotorua. Data for this event from GeoNet follow:
O: 02MAY2026 21:19:14 37.6S 178.1E MB=5.6 GEONET 794 people reported feeling this earthquake with 484 at weak intensity and 250 with light shaking and 56 with moderate intensity 3 with strong, 0 with severe and 1 with extreme intensity.
O: 02MAY2026 15:15:18 41.1S 174.7E ML=4.1 GEONET 2254 people reported feeling this earthquake near Seddon, New Zealand with 994 at weak intensity and 1078 with light shaking and 176 with moderate intensity 5 with strong, 0 with severe and 1 with extreme intensity.
O: 02MAY2026 21:19:13 37.6S 178.2E ML=5.1 NEIC NORTH ISLAND, NEW ZEALAND
O: 02MAY2026 21:19:13 37.6S 178.2E MW=5.1 EMSC OFF E. COAST OF N. ISLAND, N.Z
O: 02MAY2026 21:19:14 37.6S 178.1E MW=5.6 GEONET OFF E. COAST OF N. ISLAND, N.Z
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
660 0112 0119 0124 C1.1 (May 2, 2026) 8.8E-04
Xinjiang, China M 4.4 01:14 UT
Virgin Islands M 3.8 01:24 UT
670 0230 0245 0255 C2.5 (May 2, 2026) 3.1E-03
Nevada M 2.1 02:31 UT, M 3.1 02:46 UT
680 0537 0548 0552 C2.4 (May 2, 2026) 1.7E-03
690 0616 0625 0633 C1.9 (May 2, 2026) 1.7E-03
Antofagasta M 4.6 06:22 UT
700 0756 0810 0820 C1.8 (May 2, 2026) 2.4E-03
Central Peru M 4.0 08:22 UT
710 0922 0925 0928 C2.2 (May 2, 2026) 8.4E-04
Central Honshu M 5.7 09:28 UT
720 1020 1028 1036 C2.0 (May 2, 2026) 1.7E-03
South Sandwich Is. M 5.0 10:31 UT
Banda Sea M 5.2 10:27 UT
730 1044 1104 1126 C4.0 (May 2, 2026) 8.0E-03
Oaxaca M 3.9 10:44 UT
Java M 4.1 11:04 UT
Southern Texas M 2.1 10:46 UT
Minahasa M 4.4 11:11 UT
740 1144 1151 1155 C3.1 (May 2, 2026) 2.5E-03
750 1155 1203 1205 C3.5 (May 2, 2026) 3.3E-03
770 1205 1211 1216 C3.8 (May 2, 2026) 2.9E-03
790 1357 1404 1410 C2.4 (May 2, 2026) 1.9E-03
Nevada M 3.4 14:09 UT
New Britain M 4.6 14:16 UT
800 1511 1521 1531 C3.5 (May 2, 2026) 3.7E-03
Cook Strait M 4.3 15:15 UT
810 1531 1535 1540 C4.2 (May 2, 2026) 2.4E-03
830 1830 1838 1842 C8.7 (May 2, 2026) 3.2E-03
850 2017 2025 2030 C2.2 (May 2, 2026) 1.7E-03
Guerrero M 3.6 20:17 UT
Fox Is. M 3.9 20:21 UT
Southern Texas M 2.0 20:21 UT
Central California M 2.8 20:32 UT
Northern California M 2.1 20:17 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 4-5 active May 3. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 7, high: 10, mid-latitude: 6, time of max AP: 10:00 UT; Max AP: 4 Global Kp 2.67 2100-2400, May 2; Sunspot Number: 133; Radio Flux: 159
May 2, 2026
Notable earthquakes and events:
The full moon arrived on May 1, 2026 at 17:23 UT. Longitudes which are sub-solar (local solar noon) are near 84 West longitude while those at local solar midnight are centered near 96 East longitude. In the west these include area of Central and northwestern South America and eastern U.S. and in the east areas of western Indonesia, Myanmar, Tajikistan and western China. These areas are most likely to see tidal triggering with this full moon. A moderately large to large tidally triggered earthquake is considered moderately likely with this full moon in the period April 30-May 5, 2026.
A moderately strong earthquake occurred today in Central Honshu, Japan with M 5.7. NEIC reported it was felt
with intensity IV in Japan in Nara, Oyodo, Aichi, Nagoya, Anjo, Hyogo, Kobe, Osaka, Kusatsu, Shiga, Kyoto and III in Wakayama, Osakasayama, and Chiryu.
EMSC reported strong shaking in Japan at Kobe, Kyoto, Yoshinogawa, Taketoyo, Nagoya, Okazaki, Gifu-shi, Onomichi, Zama, Kawasaki and Urayasu.
JMA reported this earthquake with M 5.7 with maximum shaking in the area of
Kobe at 5+ on the Japanese Intensity scale. It was felt with intensity 2 in Kyushu and Shikoku in the west
to Tokyo in the East. The last shallow focus earthquake in Central or Southern Honshu, Japan with M>=5.7 within about 200 km of today's
epicenter occurred as an M 6.0 on April 1, 2016. An M 7.4 hit the area of
Kobe on May 14, 2004. At the time this summary noted:
"... The strongest events in the past three days
have occurred in western Japan where events of M 7.1, 7.0 and 6.3 injured
at least 43 people and caused minor damage. These are the strongest felt in the
Tonankai epicentral region since 1944 but no deaths have been reported.
Injuries occurred in Osaka Prefecture and in Mie, Aichi, Nara, Kyota, Shiga,
Gifu, Shizuoka, Wakayama and Hyogo prefectures. Tsunamis were associated with
both of the major earthquakes. The Japan Meteorological Agency (JMA) indicated
that these quakes were distinctive in two regards - two earthquakes of M>=7
within such a sort period are unusual in Japan although they have occurred
for example in the September 1-2, 1923 quakes in Tokyo when an M 8.3 was followed
the next day by an M 7.7. The other is that the quakes occurred in an area
where strong quakes have been rare in recent years. The last earthquake of M>7
within 100 km of this epicenter occurred as an M 8.3 on Dec. 7, 1944. In the
larger area (31-37N 135-140E) the last event of M>7 occurred at deep focus
on March 7, 1978 (M 7.6); Jan. 1, 1984 (M:7.3) and Oct. 11, 1993 (M 7.1)." (September 5, 2004) The
O: 02MAY2026 09:28:40 34.1N 135.5E ML=5.7 NEIC CENTRAL HONSHU, JAPAN
The strongest earthquake of the day was an M 5.8-6.1 in Taiwan. NEIC reported this earthquake was felt in northern Tawan with V in Chungli, Taoyuan; IV in Ilan and Hualien and III in Taipei, Nantou and Taoyuan Counties.
EMSC reported moderate shaking in Taiwan at Yilan, Taipei, Banqiao, Daxi, and Douliu.
CWB, the regional seismic network for Taiwan reported this event with M 6.1 and
that it was felt in Yilan, Hsinchu, Nantou and Hualien Counties with IV; III in Taipei, Taoyuan, Hsinchu, Miaoli, Taichung, Changhua, Taitung, and II in Keelung City, Yunlin, Chiayi, Tainan, Jaohsiung and Pingtung Counties, Taiwan.
The last earthquake in Taiwan within about 200 km of this epicenter of M>=6.1
occurred on December 27, 2025 with M 6.6. At the time this summary noted:
"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, December 27, 2025)
This event was probably promoted by tidal stresses and/or geomagnetic effects with the full moon today.
This was anticipated in the previous issue of this summary as:
"A moderate geomagnetic storm occurred late on UT April 30, 2026. This storm reached its maximum atourn 08:00 UT on May 1, 2026 with high
latitude K 5 and planetary KP in the 4's most of late April 30 and early
May 1. Strong excursions in the geomagnetic field strength occurred near 04:30 UT and again near 08:00 UT
on May 1 as shown on both GOES 19 and GOES 18 magnetometers. These would have been consistent with enhanced seismic triggering
in western U.S. and the western rim of fire along the western Pacific in
Asia. This summary had expected this type of activity at this time in the
previous issue as:
"Several sunspot groups should be returning after rotation in the next several
days. In the last rotation these caused moderately strong flares and subsequent
geomagnetic storms. In conjuction with the full moon on May 1, 2026 this
will probably break the earth out of the current seismic doldrums and
moderate to strong earthquakes are considered by this summary as likely in
the next five days. The most likely locations for such events is in central
and western South America and in eastern Asia including Western Indonesia
and the Philippines." (April 30, 2026, May 1, 2026)
Readers may note that Taiwan was near local solar noon when the geomagnetic
excursion identified above occurred.
O: 01MAY2026 12:39:55 24.9N 122.0E ML=5.8 NEIC TAIWAN
O: 01MAY2026 12:39:55 24.9N 122.1E ML=6.1 CWB TAIWAN
NEIC reported an earthquake of M 5.0 in Argentina was felt with intensity up to II-III in the area(s) of Argentina in La Rioja.
O: 02MAY2026 05:04:56 30.0S 66.5W ML=5.0 NEIC ARGENTINA
A moderate earthquake of M 5.2 today continued a series of moderate to strong
earthquakes in western Nevada. The M 4.9-5.2 was associated with a group of
light aftershocks and foreshocks. NEIC reported it was felt with intensity V in Nevada at Silver
Springs and IV in Fallon, Gardnerville, Fernley, Yerington, Sun Valley, and III in Reno and in California with IV in Kings Beach and III in San Andreas.
EMSC reported a decent jolt in Fallon, Fernley, Yerington, Carson City, Reno, Pollock Pines, Angels Camp.
A foreshock of M 4.1 was also recorded about 1.4 minutes before the mainshock and was lightly felt in Virginia City and Carson City, Nevada.
This earthquake occurred near local solar midnight and was probably promoted
by tidal stresses with today's full moon. This activity occurred at the peak
of a moderate geomagnetic storm at high latitudes (see above). This is the
strongest geomagnetic storm in the past 10 days and as it occurred when
Nevada was at local solar midnight likely promoted the M 5.2 in Nevada at that time.
This series of moderate earthquakes began with an M 5.7 on April 14, 2026.
That event occurred near the new moon. At the time this summary noted:
"A moderately strong earthquake of M 5.7 occurred today in northwestern Nevada.
More than 6000 reports of felt activity for this event were reported to NEIC. These
included maximum intensity up to VII in the epicentral area; VI in Nevada at Silver Sprints; V in Fallon, and Yerinton; IV in Fernley, Dayton, Sparks, an in California at Mokelumne, Doyle, Alta and Honewood.
A series of light aftershocks up to M 4.0 were also recorded and many were felt.
EMSC reported it was felt with strong intensity in Nevada at Fallon, Virginia City, Sparks, Carson City, Spanish Springs, Reno, East Valley, Genoa, Mogul, Gardnerville Ranchos, and in California at Truckee, Foresthill, Auburn, Deer Park, Sonora, Rancho Cordova, Linda, Sacramento, Woodbridge, Lodi and lightly as far as 200 km from the epicenter in Oakley.
NEIC reported intensity up to VII in the epicentral area of Fallon. This is the
strongest earthquake within about 150 km of this epicenter since an M 5.8 on December 9, 2024.
The last event in the area with significantly larger magnitude was an M 6.0
on July 8, 2021. At the time of the December, 2024 earthquake this summary
noted:
"A moderately strong M 5.8 hit the region of northern Nevada near the California border today. It was followed by a strong series of light aftershocks.
NEIC reported maximum shaking of VI was felt in Nevada at Dayton, Fallon, Fernley, Minden and III in Gardnerville, Glenbrook, Hawthorne, Lovelock, Indian Sprints, Austin.
Preliminary reports do not indicate any major damage with this earthquake.
Minor damage such as items fallen from grocery shelves did occur near the
epicenter. More than 12,000 responded to NEIC that they had felt this earthquake.
The last earthquake within about 200 km of this epicenter in northern Nevada with
M>=5.8 occurred on July 8, 2021 with M 6.0. The only other event in the region
in the past 35 years was an M 6.1 on September 12, 1994. At the time of the July, 2021
event this summary noted:
"The earthquake of M 6.0 in California was preceded about an hour earlier by an M 4.4
in Southeastern Alaska. NEIC reported this earthquake was felt with intensity IV in Alaska at Haines, Skagway and II-III in Elfin Cove, Gustavus, Hoonah, Juneau, Douglas, and in Whitehorse, Yukon, Canada.
Several other indicators had suggested that a strong earthquake was imminent in
California at this time. For example when a light earthquake occurred in western
South Dakota on June 16 ..." (July 8, 2021)
Some indication of a strong enhancement of regional seismicity inland from
major earthquakes off northern California has previously been commented on
in this summary. For example an M 4.2 in Utah - the second strongest earthquake
in Utah in the past four years - occurred minutes after the M 7.0 in California.
At the time this summary noted:
"The mainshock off northern California was also accompanied by an M 4,2 several minutes
later in Utah. This coincidence has been noted in this summary previously.
For example when an M 5.7 occurred in northern Utah on March 18, 2020 and was followed
several hours later by an M 5.2 off the coast of northern California this summary noted:
"A moderate earthquake was also felt in Northern California today. This event of M 5.0-5.2 occurred near the coast and was felt with maximum intensity VI in Ferndale and Scotia according to data from NEIC. Intensity V shaking occurred in California at Rio Dell, Fortuna and Eureka and IV in Petrolia and Hydesville with lesser shaking in Lleta, Carlotta and Myers Flat. Light shaking was reported as far as Central California and southern Oregon. Several light aftershocks followed.
This is probably a regional aftershock of the M 5.8 which hit the area to the
west on March 9, 2020 in a regional activation from Alaska to southern California."
This summary had noted this at the time" (March 18, 2020)
The mainshock in Nevada may have been promoted by a C2.3 solar flare (#5700)
which was finishing up at the time of this earthquake." (December 9, 2024)
This summary had provided some warning that such an event was possible
at this time in the previous issue of this summary as:
"A strong geomagnetic excursion occurred on the GOES 19 magnetometer on April 13, 2026
at about 07:40-08:00 UT. This could affect areas near 60 East longitude and 120 West
longitude including area of Pakistan and Iran in the East and California
and western North America in the west. Expect moderate enhancement in
seismicity during the several hours after this change in geomagnetic field strength." (April 13, 2026)
Today's earthquake was within a couple of minutes of local solar midnight when
this geomagnetic effect peaked near 07:56 UT (00:00 UT local solar time) on GOES 19 Magnetometer
when an arcjet stabilizing maneuver corrected the satellite position.
This epicenter is at 108 degrees from the M 7.6 in the Molucca Sea of April 1. 2026.
This is at the distance where reflected and refracted seismic energy returns
to the surface following major earthquakes such as the event in the Molucca Sea." (April 14, 2026)
This area had been noted in the previous issue of this summary as a possible
area to wach with the full moon today as:
"NEIC reported earthquakes of M 3.3, 2.7 in Nevada were felt with intensity up to II-III in the area(s) of Nevada in Silver Springs, Folsom and Gardnerville.
These are continuing aftershocks of event of M 5.0 and M 5.8 earlier this week.
As the aftershocks are still quite active, it is possible, especially with
the full moon of May 1 that another moderate earthquake could occur in this
area most likely due to tidal effects around local solar noon or midnight (0800 UT or 2000 UT). This is a pattern seen in this region in the past - especially in 1954." (April 30, 2026)
This epicenter is at the fifth node (72 degrees) from Honshu and may have
been affected by energy from that source" (April 14, 2026)
NEIC reported aftershocks in Nevada of M 3.0, 3.0, 2.5 were felt with intensity up to II-III in the area(s) of Nevada in Reno and Fallon on May 2.
O: 01MAY2026 08:17:19 39.3N 119.0W ML=5.2 NEIC NEVADA
O: 01MAY2026 08:17:19 39.3N 119.0W ML=5.2 EMSC NEVADA
O: 02MAY2026 02:49:28 39.3N 119.1W ML=3.0 NEIC NEVADA
O: 02MAY2026 00:04:58 39.3N 119.1W ML=3.0 NEIC NEVADA
EMSC reported an earthquake of M 4.0 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar in Yangoon.
O: 01MAY2026 14:51:43 16.5N 95.8W ML=4.0 EMSC MYANMAR
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 May 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
470 0246 0252 0257 C1.5 (May 1, 2026( 1.0E-03
Molucca M 3.8 02:57 UT
480 0412 0419 0422 C1.8 (May 1, 2026( 9.2E-04
Chiapas M 4.4 04:30 UT
500 0654 0659 0707 C1.4 (May 1, 2026( 1.1E-03
Kuril Is. M 4.2 06:59 UT
510 0847 0850 0853 C1.4 (May 1, 2026( 5.4E-04
520 0929 0933 0940 C1.9 (May 1, 2026( 1.2E-03
Siberia M 4.2 0931 UT
Papua M 4.0 09:31 UT
560 1410 1414 1416 C1.6 (May 1, 2026( 6.5E-04
580 1524 1529 1533 C7.4 (May 1, 2026( 2.4E-03
610 1814 1821 1824 C1.2 (May 1, 2026( 7.4E-04
630 2310 2315 2320 C1.3 (May 1, 2026( 8.3E-04
640 2321 2329 2335 C2.8 (May 1, 2026( 1.9E-03
Northern California M 2.7 23:32 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 2 and 4 active May 3. Solar M-flare chance: 40% X-class: 5% proton storm: 1%
AP Indicies: global: 14, high: 20, mid-latitude: 10, time of max AP: 08:00 UT; Max AP: 5 Global Kp 4.33 0300-0600, May 1; Sunspot Number: 158; Radio Flux: 145
May 1, 2026
Notable earthquakes and events:
A moderate geomagnetic storm occurred late on UT April 30, 2026. This storm reached its maximum at about 08:00 UT on May 1, 2026 with high
latitude K 5 and planetary KP in the 4's most of late April 30 and early
May 1. Strong excursions in the geomagnetic field strength occurred near 04:30 UT and again near 08:00 UT
on May 1 as shown on both GOES 19 and GOES 18 magnetometers. These would have been consistent with enhanced seismic triggering
in western U.S. and the western rim of fire along the western Pacific in
Asia. This summary had expected this type of activity at this time in the
previous issue as:
"Several sunspot groups should be returning after rotation in the next several
days. In the last rotation these caused moderately strong flares and subsequent
geomagnetic storms. In conjunction with the full moon on May 1, 2026 this
will probably break the earth out of the current seismic doldrums and
moderate to strong earthquakes are considered by this summary as likely in
the next five days. The most likely locations for such events is in central
and western South America and in eastern Asia including Western Indonesia
and the Philippines." (April 30, 2026)
The full moon will arrive on May 1, 2026 at 17:23 UT. Longitudes which are sub-solar (local solar noon) are near 84 West longitude while those at local solar midnight are centered near 96 East longitude. In the west these include area of Central and northwestern South America and eastern U.S. and in the east areas of western Indonesia, Myanmar, Tajikistan and western China. These areas are most likely to see tidal triggering with this full moon. A moderately large to large tidally triggered earthquake is considered moderately likely with this full moon in the period April 30-May 5, 2026.
A moderate earthquake of M 5.2 today continued a series of moderate to strong
earthquakes in western Nevada. The M 4.9-5.2 was associated with a group of
light aftershocks and foreshocks. NEIC reported it was felt with intensity V in Nevada at Silver
Springs and IV in Fallon, Gardnerville, Fernley, Yerington, Sun Valley, and III in Reno and in California with IV in Kings Beach and III in San Andreas.
EMSC reported a decent jolt in Fallon, Fernley, Yerington, Carson City, Reno, Pollock Pines, Angels Camp.
A foreshock of M 4.1 was also recorded about 1.4 minutes before the mainshock and was lightly felt in Virginia City and Carson City, Nevada.
This earthquake occurred near local solar midnight and was probably promoted
by tidal stresses with today's full moon. This activity occurred at the peak
of a moderate geomagnetic storm at high latitudes (see above). This is the
strongest geomagnetic storm in the past 10 days and as it occurred when
Nevada was at local solar midnight likely promoted the M 5.2 in Nevada at that time.
This series of moderate earthquakes began with an M 5.7 on April 14, 2026.
That event occurred near the new moon. At the time this summary noted:
"A moderately strong earthquake of M 5.7 occurred today in northwestern Nevada.
More than 6000 reports of felt activity for this event were reported to NEIC. These
included maximum intensity up to VII in the epicentral area; VI in Nevada at Silver Springs; V in Fallon, and Yerington; IV in Fernley, Dayton, Sparks, an in California at Mokelumne, Doyle, Alta and Homewood.
A series of light aftershocks up to M 4.0 were also recorded and many were felt.
EMSC reported it was felt with strong intensity in Nevada at Fallon, Virginia City, Sparks, Carson City, Spanish Springs, Reno, East Valley, Genoa, Mogul, Gardnerville Ranchos, and in California at Truckee, Foresthill, Auburn, Deer Park, Sonora, Rancho Cordova, Linda, Sacramento, Woodbridge, Lodi and lightly as far as 200 km from the epicenter in Oakley.
NEIC reported intensity up to VII in the epicentral area of Fallon. This is the
strongest earthquake within about 150 km of this epicenter since an M 5.8 on December 9, 2024.
The last event in the area with significantly larger magnitude was an M 6.0
on July 8, 2021. At the time of the December, 2024 earthquake this summary
noted:
"A moderately strong M 5.8 hit the region of northern Nevada near the California border today. It was followed by a strong series of light aftershocks.
NEIC reported maximum shaking of VI was felt in Nevada at Dayton, Fallon, Fernley, Minden and III in Gardnerville, Glenbrook, Hawthorne, Lovelock, Indian Sprints, Austin.
Preliminary reports do not indicate any major damage with this earthquake.
Minor damage such as items fallen from grocery shelves did occur near the
epicenter. More than 12,000 responded to NEIC that they had felt this earthquake.
The last earthquake within about 200 km of this epicenter in northern Nevada with
M>=5.8 occurred on July 8, 2021 with M 6.0. The only other event in the region
in the past 35 years was an M 6.1 on September 12, 1994. At the time of the July, 2021
event this summary noted:
"The earthquake of M 6.0 in California was preceded about an hour earlier by an M 4.4
in Southeastern Alaska. NEIC reported this earthquake was felt with intensity IV in Alaska at Haines, Skagway and II-III in Elfin Cove, Gustavus, Hoonah, Juneau, Douglas, and in Whitehorse, Yukon, Canada.
Several other indicators had suggested that a strong earthquake was imminent in
California at this time. For example when a light earthquake occurred in western
South Dakota on June 16 ..." (July 8, 2021)
Some indication of a strong enhancement of regional seismicity inland from
major earthquakes off northern California has previously been commented on
in this summary. For example an M 4.2 in Utah - the second strongest earthquake
in Utah in the past four years - occurred minutes after the M 7.0 in California.
At the time this summary noted:
"The mainshock off northern California was also accompanied by an M 4,2 several minutes
later in Utah. This coincidence has been noted in this summary previously.
For example when an M 5.7 occurred in northern Utah on March 18, 2020 and was followed
several hours later by an M 5.2 off the coast of northern California this summary noted:
"A moderate earthquake was also felt in Northern California today. This event of M 5.0-5.2 occurred near the coast and was felt with maximum intensity VI in Ferndale and Scotia according to data from NEIC. Intensity V shaking occurred in California at Rio Dell, Fortuna and Eureka and IV in Petrolia and Hydesville with lesser shaking in Lleta, Carlotta and Myers Flat. Light shaking was reported as far as Central California and southern Oregon. Several light aftershocks followed.
This is probably a regional aftershock of the M 5.8 which hit the area to the
west on March 9, 2020 in a regional activation from Alaska to southern California."
This summary had noted this at the time" (March 18, 2020)
The mainshock in Nevada may have been promoted by a C2.3 solar flare (#5700)
which was finishing up at the time of this earthquake." (December 9, 2024)
This summary had provided some warning that such an event was possible
at this time in the previous issue of this summary as:
"A strong geomagnetic excursion occurred on the GOES 19 magnetometer on April 13, 2026
at about 07:40-08:00 UT. This could affect areas near 60 East longitude and 120 West
longitude including area of Pakistan and Iran in the East and California
and western North America in the west. Expect moderate enhancement in
seismicity during the several hours after this change in geomagnetic field strength." (April 13, 2026)
Today's earthquake was within a couple of minutes of local solar midnight when
this geomagnetic effect peaked near 07:56 UT (00:00 UT local solar time) on GOES 19 Magnetometer
when an arcjet stabilizing maneuver corrected the satellite position.
This epicenter is at 108 degrees from the M 7.6 in the Molucca Sea of April 1. 2026.
This is at the distance where reflected and refracted seismic energy returns
to the surface following major earthquakes such as the event in the Molucca Sea." (April 14, 2026)
This area had been noted in the previous issue of this summary as a possible
area to wach with the full moon today as:
"NEIC reported earthquakes of M 3.3, 2.7 in Nevada were felt with intensity up to II-III in the area(s) of Nevada in Silver Springs, Folsom and Gardnerville.
These are continuing aftershocks of event of M 5.0 and M 5.8 earlier this week.
As the aftershocks are still quite active, it is possible, especially with
the full moon of May 1 that another moderate earthquake could occur in this
area most likely due to tidal effects around local solar noon or midnight (0800 UT or 2000 UT). This is a pattern seen in this region in the past - especially in 1954." (April 30, 2026)
This epicenter is at the fifth node (72 degrees) from Honshu and may have
been affected by energy from that source" (April 14, 2026)
O: 29APR2026 15:55:12 39.3N 119.1W ML=3.2 NEIC NEVADA
O: 29APR2026 10:24:01 39.3N 119.1W ML=2.0 EMSC NEVADA
O: 29APR2026 10:39:53 39.3N 119.1W ML=2.5 EMSC NEVADA
O: 29APR2026 14:16:59 39.3N 119.0W ML=2.7 EMSC NEVADA
O: 29APR2026 14:47:48 39.3N 119.1W ML=2.1 EMSC NEVADA
O: 29APR2026 20:45:05 39.3N 119.1W ML=2.2 EMSC NEVADA
O: 01MAY2026 08:17:19 39.3N 119.0W ML=4.9 NEIC NEVADA
O: 01MAY2026 08:17:19 39.3N 119.0W ML=5.2 EMSC NEVADA
NEIC reported an earthquake of M 3.7 off the coast of northern California was felt with intensity up to II-III in the area(s) of northern California in Eureka and Arcata.
O: 01MAY2026 01:58:41 40.3N 124.6W ML=3.7 NEIC OFFSHORE NORTHERN CALIFORNIA
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 in Fremont, Morgan Hill, San Jose, Castro Valley, Oakland.
This earthquake may have been promoted by a C1.8 solar flare (#460) which
began at the same time as the earthquake not long after local solar noon.
Data for this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
460 2245 2250 2255 C1.8 (April 30, 2026) 1.0E-03
Northern California M 2.7 22:44 UT
Cook Strait, New Zealand M 4.2 22:57 UT
New Ireland M 4.8 22:58 UT
O: 30APR2026 22:43:37 37.3N 121.6W ML=2.8 NEIC CENTRAL CALIFORNIA
The strongest earthquake in the world today was an M 5.7 in Papua New Guinea near Lorengau.
NEIC reported it was likely felt with intensity III in this epicentral area.
This event occurred near local solar midnight and was probably promoted by tidal
stresses with today's full moon which maximize near this hour.
O: 30APR2026 13:27:01 3.4S 148.8E ML=5.7 NEIC CENTRAL CALIFORNIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 30, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
340 0016 0021 0023 C1.5 (April 30, 2026) 7.3E-04
350 0024 0031 0041 C5.1 (April 30, 2026) 3.9E-03
Southern Alaska M 3.2 00:26 UT
380 0133 0152 0208 C1.9 (April 30, 2026) 3.5E-03
390 0208 0219 0226 C1.5 (April 30, 2026) 1.8E-03
Sulawesi M 4.4 02:09 UT
410 0911 0917 0921 C3.3 (April 30, 2026) 2.4E-03
420 0935 0940 0945 C3.7 (April 30, 2026) 2.4E-03
460 2245 2250 2255 C1.8 (April 30, 2026) 1.0E-03
Northern California M 2.7 22:44 UT
Cook Strait, New Zealand M 4.2 22:57 UT
New Ireland M 4.8 22:58 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled May 1-2 quiet May 3. Solar M-flare chance: 50% X-class: 10% proton storm: 10%
AP Indicies: global: 15, high: 17, mid-latitude: 12, time of max AP: 16:00 UT; Max AP: 4 Global Kp 4.67 2100-2400, April 30; Sunspot Number: 138; Radio Flux: 143
April 30, 2026
Notable earthquakes and events:
It was another quiet day in global seismicity today. The largest earthquakes
occurred in the Prince Edward Island area of the South Indian Ocean with magnitude
up to M 5.2 in a series. The antipode of this epicenter is off the coast of
Oregon where volcanic earthquakes are currently active and could be moderately
affected by this activity in the Prince Edward Islands. The strongest solar flare
of the day occurred with maximum at about 22:04 UT. An M 5.0, the largest
felt earthquake in the world today also occurred at 22:04 UT and was probably
promoted by SFE associated with this flare (see below).
Several sunspot groups should be returning after rotation in the next several
days. In the last rotation these caused moderately strong flares and subsequent
geomagnetic storms. In conjuction with the full moon on May 1, 2026 this
will probably break the earth out of the current seismic doldrums and
moderate to strong earthquakes are considered by this summary as likely in
the next five days. The most likely locations for such events is in central
and western South America and in eastern Asia including Western Indonesia
and the Philippines.
The full moon will arrive on May 1, 2026 at 17:23 UT. Longitudes which are sub-solar (local solar noon) are near 84 West longitude while those at local solar midnight are centered near 96 East longitude. In the west these include area of Central and northwestern South America and eastern U.S. and in the east areas of western Indonesia, Myanmar, Tajikistan and western China. These areas are most likely to see tidal triggering with this full moon. A moderately large to large tidally triggered earthquake is considered moderately likely with this full moon in the period April 30-May 5, 2026.
NEIC reported an earthquake of M 5.0 in Northern Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Northern Mindanao, Philippines in Dapa Caraga.
This was the strongest felt earthquake in the world today.
This event may have been promoted by a strong geomagnetic field drop at 22:00 UT recorded
on GOES 18 and 19 satellites. This was a sudden drop in geomagnetic field
strength that lasted for several minutes.
This epicenter is at the 11th node (34 degrees) from Honshu and may have
been promoted by energy from that source.
O: 29APR2026 22:04:37 8.9N 126.6E ML=5.0 NEIC MINDANAO, PHILIPPINES
O: 29APR2026 22:04:37 9.0N 126.6E MB=5.0 EMSC MINDANAO, PHILIPPINES
NEIC reported earthquakes of M 5.2, 5.1, 5.0 ... occurred today in the Prince Edwards
Island region south of South Africa in the Indian Ocean. These were not reported
felt in this remote epicentral area. The antipode is at 45N 143W off the coast
of Oregon and not far from current volcanism in the area.
This could be encouraged by antipodal effects from these quakes in the South
Indian Ridge. This series may have been promoted by solar flare 290 (C1.6)
as it began near the maximum of that flare. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
290 1608 1616 1622 C1.6 (April 29, 2026) 1.4E-03
Prince Edward Is. M 5.1 16:11 UT
These epicenters are at the fourth node (90 degrees) from the Molucca Sea and at
105 degrees from Vanuatu and may have been promoted by energy from those sources.
O: 29APR2026 16:41:45 44.6S 37.3E ML=5.2 NEIC PRINCE EDWARD ISLANDS REGION
O: 29APR2026 16:31:05 44.6S 37.3E ML=5.1 NEIC PRINCE EDWARD ISLANDS REGION
O: 29APR2026 16:27:36 44.6S 37.3E ML=5.0 NEIC PRINCE EDWARD ISLANDS REGION
O: 29APR2026 16:11:26 44.6S 37.3E ML=5.1 NEIC PRINCE EDWARD ISLANDS REGION
NEIC reported seismic disturbances of M 4.4-4.6, 3.6, 2.8 ... in Southern Nevada were felt with intensity up to II-III in the area(s) of Southern Nevada near Alamo.
EMSC reports buildings shook in Las Vegas, Nevada.
The series of such events near the Nuclear Testing facilities north of Las
Vegas suggests these may be of artificial origin. This is consistent with
the timing of the largest of these aftershocks - within three minutes of local solar midnight
(07:44:59 UT (within one second of 07:45 UT or 00:02 LST) at a depth of 0 km- a surface event). The mainshock in the series was an M 4.4-4.6 early on April 29, 2026
Some of the moment tensor solutions are off and suggest an explosive source
for this event. Moment tensors for the M 3.6 from EMSC and NEIC are "Temporarily unavailable". If one of the aftershocks is clearly artificial, the original
event is most likely also artificial and since non-nuclear explosions
do not reach M 4.4-4.6 it is likely to be a nuclear test.
The Test Ban Treaty forbids tests above this magnitude, so the exact
magnitude of this event (whether artificial or natural) is important
and will be a matter of some argument.
On the other side of the argument, this earthquake coincided with the
beginning of solar flare 270 - a C2.1 flare and may have been promoted
by SFE from that flare. The M 3.6 (aftershock?) on April 30 had no accompanying flare
nor geomagnetic excursion associated with it. Data on that flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0000 0030 0100 C5.1 (April 30, 2026) 4.1E-03
270 1505 1509 1515 C2.1 (April 29, 2026) 1.1E-03
Nevada M 4.6 15:06 UT
These epicenters area at the fourth node (90 degrees) from Vanuatu and
may have been promoted by energy from that source, if natural.
O: 29APR2026 15:06:13 37.1N 115.3W ML=4.4 NEIC SOUTHERN NEVADA
O: 29APR2026 15:06:14 37.1N 115.3W MW=4.6 EMSC NEVADA
O: 29APR2026 15:33:17 37.1N 115.3W ML=3.2 EMSC NEVADA
O: 29APR2026 16:48:25 37.1N 115.3W ML=2.8 EMSC NEVADA
O: 30APR2026 00:10:30 37.1N 115.3W ML=2.6 EMSC NEVADA
O: 30APR2026 07:44:59 37.1N 115.3W ML=3.6 EMSC NEVADA
O: 29APR2026 15:06:15 37.1N 115.3W ML=4.6 EMSC SOUTHERN NEVADA
O: 30APR2026 07:44:59 37.1N 115.3W ML=3.6 NEIC SOUTHERN NEVADA
O: 29APR2026 16:48:25 37.1N 115.3W ML=2.8 NEIC SOUTHERN NEVADA
Among other events today that may have been excited by solar flare effects (SFE)
were an M 4.6 in the South west Indian Ridge and an M 3.8 in Puerto Rico.
The event in the Southwest Indian Ridge was not reported felt in that
remote area. It occurred within minutes of local solar midnight with
solar flare 310 (C1.6). Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
310 2040 2045 2047 C1.6 (April 29, 2026) 6.7E-04
Nevada M 2.2 20:45 UT
Southwest Indian Ridge M 4.6 20:39 UT
This epicenter is at the sixth node (60 degrees) from Malaysia and may have
been promoted by energy from that source.
O: 29APR2026 20:38:47 27.8S 64.0E MB=4.6 EMSC SOUTHWEST INDIAN RIDGE
NEIC reported an earthquake of M 3.4 in greater Los Angeles, California was felt with intensity up to II-III in the area(s) of greater Los Angeles, California in Grand Terrace, Lake Elsinore, San Bernardino, Menifee, March AFB, Riverside.
EMSC reported a loud sound accompanied the earthquake with moderate shaking in California at Grand Terrace, Moreno Valley, Highgrove, Riverside, Rubidoux, Sunnyslope, Pedley, Glen Avon, Quail Valley, Rancho Cucamonga, Sun City, Hemet, Glendora, Cathedral City, Lancaster.
A number of aftershocks were also lightly felt in the epicentral area.
O: 30APR2026 03:48:04 34.0N 117.2W ML=3.4 NEIC GREATER LOS ANGELES, CALIFORNIA
O: 29APR2026 11:33:48 34.0N 117.2W ML=2.0 EMSC GREATER LOS ANGELES AREA, CALI
O: 29APR2026 14:47:47 34.0N 116.8W ML=3.0 EMSC SOUTHERN CALIFORNIA
O: 30APR2026 03:48:04 34.0N 117.2W ML=3.1 EMSC GREATER LOS ANGELES AREA, CALIF.
O: 30APR2026 03:48:58 34.0N 117.2W ML=2.6 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 3.7 in Southeastern Alaska was felt with intensity up to II-III in the area(s) of Southeastern Alaska near Yakutat,
This epicenter is at the seventh node (51 degrees) from Honshu and at the fourth node
(90 degrees) from the Molucca Sea and Malaysia and may have been promoted by
constructive interference of energy from those sources.
O: 30APR2026 01:05:38 60.4N 139.5W ML=3.7 NEIC SOUTHEASTERN ALASKA
O: 30APR2026 01:05:40 60.5N 139.6W ML=3.8 EMSC SOUTHERN YUKON TERRITORY, CANA
NEIC reported earthquakes of M 3.3, 2.7 in Nevada were felt with intensity up to II-III in the area(s) of Nevada in Silver Springs, Folsom and Gardnerville.
These are continuing aftershocks of event of M 5.0 and M 5.8 earlier this week.
As the aftershocks are still quite active, it is possible, especially with
the full moon of May 1 that another moderate earthquake could occur in this
area most likely due to tidal effects around local solar noon or midnight (0800 UT or 2000 UT). This is a pattern seen in this region in the past - especially in 1954.
This epicenter is at the fifth node (72 degrees) from Honshu and may have
been affected by energy from that source.
O: 29APR2026 15:55:12 39.3N 119.1W ML=3.2 NEIC NEVADA
O: 29APR2026 10:24:01 39.3N 119.1W ML=2.0 EMSC NEVADA
O: 29APR2026 10:39:53 39.3N 119.1W ML=2.5 EMSC NEVADA
O: 29APR2026 14:16:59 39.3N 119.0W ML=2.7 EMSC NEVADA
O: 29APR2026 14:47:48 39.3N 119.1W ML=2.1 EMSC NEVADA
O: 29APR2026 20:45:05 39.3N 119.1W ML=2.2 EMSC NEVADA
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 in Forest Falls, Rorrance, Palm Springs, Perris, Murrieta, Yucaipa, Riverside, Banning, Winchester, Redlands.
O: 29APR2026 14:47:47 34.0N 116.8W ML=3.0 NEIC SOUTHERN CALIFORNIA
O: 29APR2026 14:47:47 34.0N 116.8W ML=3.0 EMSC SOUTHERN CALIFORNIA
EMSC reported an earthquake of M 4.1 in India was felt with intensity up to IV in the area(s) of India in Kesinga.
This epicenter is at the fourth node (90 degrees) from Vanuatu and may have been promoted by energy from that source.
O: 29APR2026 14:12:21 19.7N 82.6E ML=4.1 EMSC INDIA
EMSC reported an earthquake of M 4.0 in Myanmar was felt with intensity up to IV in the area(s) of Myanmar in Mandalay.
O: 29APR2026 08:50:20 21.6N 96.0E ML=4.0 EMSC MYANMAR
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 29, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
10 0000 0007 0016 C1.7 (April 29, 2026) 1.5E-03
30 0037 0043 0049 C2.4 (April 29, 2026) 1.5E-03
Honshu M 4.4 00:43 UT
40 0100 0108 0112 C2.1 (April 29, 2026) 1.3E-03
60 0344 0354 0405 C3.0 (April 29, 2026) 2.7E-03
Guerrero M 4.2 03:41 UT
Coast No. California M 3.0 03:53 UT
Puerto Rico M 3.8 04:00 UT
70 0439 0445 0450 C5.1 (April 29, 2026) 2.4E-03
Nevada M 2.4 04:41 UT
110 0605 0614 0623 C1.8 (April 29, 2026) 1.6E-03
Peru M 4.8 06:12 UT
Spain M 3.6 06:23 UT
Xizang M 4.8 06:30 UT
Indian-Antarctic Ridge M 4.5 06:34 UT
130 0659 0704 0706 C1.3 (April 29, 2026) 7.8E-04
140 0720 0728 0735 C2.1 (April 29, 2026) 1.7E-03
Xinjiang M 4.3 07:20 UT
180 1118 1134 1144 C2.2 (April 29, 2026) 2.9E-03
Chiapas M 4.0 11:28 UT
Los Angeles CA M 2.0 11:34 UT
200 1155 1202 1208 C2.0 (April 29, 2026) 1.5E-03
240 1403 1413 1419 C1.9 (April 29, 2026) 1.6E-03
Nevada M 2.7 14:16 UT
270 1505 1509 1515 C2.1 (April 29, 2026) 1.1E-03
Nevada M 4.6 15:06 UT
280 1544 1551 1601 C1.5 (April 29, 2026) 1.5E-03
Mindanao M 3.8 15:50 UT
Papua M 4.1 15:53 UT
290 1608 1616 1622 C1.6 (April 29, 2026) 1.4E-03
Prince Edward Is. M 5.1 16:11 UT
300 1930 1936 1942 C2.0 (April 29, 2026) 1.4E-03
Molucca M 4.2 19:29 UT
Nevada M 2.0 19:30 UT
Myanmar M 3.7 19:40 UT
310 2040 2045 2047 C1.6 (April 29, 2026) 6.7E-04
Nevada M 2.2 20:45 UT
Southwest Indian Ridge M 4.6 20:39 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active April 30 unsettled May 1 quiet May 2. Solar M-flare chance: 65% X-class: 10% proton storm: 15%
AP Indicies: global: 4, high: 2, mid-latitude: 6, time of max AP: 20:00 UT; Max AP: 2 Global Kp 1.67 1400-1700, April 29; Sunspot Number: 142; Radio Flux: 143
April 29, 2026
Notable earthquakes and events:
It was a quiet day in global seismicity today. The most widely felt earthquakes
occurred in the area of Athens, Greece with M 4.7 and M 4.8 but were not
damaging. The only event in the world of M>=5 today was an M 5.2 at a deep
focus in the area of Fiji. It was not reported felt in this remote area.
O: 28APR2026 15:28:15 18.6S 177.7W MB=5.2 EMSC FIJI ISLANDS
O: 28APR2026 15:28:15 18.6S 177.7W MW=5.2 EMSC FIJI REGION
NEIC reported an earthquake of M 2.7 in Central California was felt with intensity up to II-III in the area(s) of Central California at Bass Lake, Mariposa, Oakhurst, Friant, Coarsegold and II in Ahwahnee.
O: 29APR2026 02:57:39 37.3N 119.8W MB=2.7 NEIC CENTRAL CALIFORNIA
O: 29APR2026 02:57:39 37.3N 119.8W MD=2.5 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.2 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Kodiak.
EMSC reported it was felt in Kodiak Station, Alaska.
O: 29APR2026 02:36:25 57.4N 152.4W MB=4.2 NEIC SOUTHERN ALASKA
O: 29APR2026 02:36:25 57.4N 152.4W MB=4.3 EMSC KODIAK ISLAND REGION, ALASKA
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 Granite Bay, Cirtus Heights, Rocklin, Orangevale, Roseville, Penryn, Loomnis, and Rescue.
EMSC reported this earthquake near Sacramento, California was felt with moderate shaking in Roseville, Orangevale, Folsom, Fair Oaks and Gold River.
This epicenter in central California is at the fifth node (72 degrees) from
Honshu, Japan and may have been promoted by energy from that source.
O: 29APR2026 01:35:57 38.7N 121.2W MB=2.8 NEIC NORTHERN CALIFORNIA
O: 29APR2026 01:35:55 38.8N 121.2W MD=2.6 EMSC SACRAMENTO URBAN AREA, CALIF.
NEIC reported an earthquake of M 2.6 in Greater Los Angeles, California was felt with intensity up to II-III in the area(s) of Greater Los Angeles, California in Moreno Valley, Colton, March AFB Redlands, Riverside, San Bernardino and Moreno Valley.
EMSC reported it was felt with strong intensity in Moreno Valley, California.
O: 28APR2026 20:11:47 34.0N 117.2W MB=2.6 NEIC GREATER LOS ALGELES, CALIFORNIA
O: 28APR2026 20:11:47 34.0N 117.2W ML=2.6 EMSC GREATER LOS ANGELES AREA, CALI
NEIC reported an earthquake of M 3.5 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii in Hakalau, Kealakekua, Captain Cook, Kamuela, Pahala, Mountain View, Kailua Kona, and II in Naalehu, Holualoa and Waikoloa.
O: 28APR2026 19:26:43 19.2N 155.5W MB=3.5 NEIC HAWAII
O: 28APR2026 09:32:12 19.0N 155.5W ML=3.0 EMSC ISLAND OF HAWAII, HAWAII
O: 28APR2026 19:26:41 19.2N 155.5W ML=3.6 EMSC ISLAND OF HAWAII, HAWAII
O: 28APR2026 20:48:36 19.2N 155.5W ML=3.3 EMSC ISLAND OF HAWAII, HAWAII
NEIC reported an earthquake of M 3.0 in Utah was felt with intensity up to II-III in the area(s) of Utah near Panguitch.
O: 28APR2026 17:16:39 37.9N 112.2W MB=3.0 NEIC UTAH
O: 28APR2026 17:16:38 37.9N 112.2W ML=3.0 EMSC UTAH
O: 28APR2026 17:19:34 37.9N 112.2W ML=2.1 EMSC UTAH
O: 28APR2026 17:27:29 37.9N 112.2W ML=2.0 EMSC UTAH
NEIC reported an earthquake of M 4.7 in Central Chile was felt with intensity up to II-III in the area(s) of Central Chile in Santiago.
EMSC reported it was felt with moderate intensity in San Vicente, Vina del Mar.
These epicenters in Chile are located at the fourth node (90 degrees) from Tonga
and may have been promoted by energy from that source.
O: 28APR2026 14:55:23 33.9S 72.2W MB=4.7 NEIC CENTRAL CHILE
O: 28APR2026 14:55:21 34.0S 72.2W MB=4.7 EMSC OFFSHORE O'HIGGINS, CHILE
O: 28APR2026 10:04:18 34.0S 72.2W Mw=4.2 EMSC OFFSHORE O'HIGGINS, CHILE
O: 28APR2026 10:06:22 34.0S 72.2W Mw=4.1 EMSC OFFSHORE O'HIGGINS, CHILE
O: 28APR2026 12:54:43 34.0S 72.2W ML=4.4 EMSC OFFSHORE O'HIGGINS, CHILE
NEIC reported an earthquake of M 3.8 in Southeastern Alaska was felt with intensity up to II-III in the area(s) of Southeastern Alaska near McCarthy.
This epicenter Alaska is located at the fourth node (90 degrees) from the Molucca Sea and from
Malaysia and may have been promoted by constructive energy interference from those sources.
O: 28APR2026 13:26:08 61.4N 140.4W MB=3.8 NEIC SOUTHEASTERN ALASKA
O: 28APR2026 13:26:09 61.4N 140.2W ML=4.0 EMSC SOUTHERN YUKON TERRITORY, CANA
NEIC reported earthquakes of M 4.8 and M 4.7 in Greece were felt with intensity up to II-III in the area(s) of Greece with V in Skiathos, Magnisia; IV in Volos, Skiathos and Mileiai, Athens and II in Larisa.
EMSC reported moderate to strong shaking in Greece at Argalasti, Volos, Loutra Aidhipsou, Almyros, Livanates, Patitirion, Livanates, Nea Artaki, Lamia, Livadeia, Larisa, Acharnes, Lykovrysi, Zefyri, Nea Filadelfeia, Irakleio, Marousi, Karditsa, Ilion, Filothei, Khalandrion, among others.
The first of these may have been promoted by SFE from solar flare 9710 (C3.1)
which began at the same time as this M 4.7 near local solar noon in Greece. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9710 1112 1118 1121 C3.1 (April 28, 2026) 1.5E-03
Greece M 4.7 11:12 UT
These earthquakes in the Aegean Sea are located at 100 km degrees from
the Molucca Sea and may have been promoted by energy from those sources.
O: 28APR2026 13:07:46 39.2N 23.4E MB=4.8 NEIC GREECE
O: 28APR2026 13:07:45 39.2N 23.4E MW=4.8 EMSC AEGEAN SEA
O: 28APR2026 11:12:23 39.2N 23.4E Mw=4.7 EMSC AEGEAN SEA
O: 28APR2026 11:12:23 39.3N 23.3E MB=4.7 NEIC GREECE
EMSC reported an earthquake of M 4.2 in Tajikistan was felt with intensity up to IV in the area(s) of Tajikistan in Dushanbe.
O: 28APR2026 16:42:30 39.0N 70.6E MB=4.2 EMSC TAJIKISTAN
These epicenters in Tajikistan and Afghanistan are located at the seventh node (51 degrees)
from Malaysia and at 103 degrees from Vanuatu and may have been promoted by
constructive energy interference from those sources.
EMSC reported an earthquake of M 4.6 in Afghanistan was felt with intensity up to IV in the area(s) of Afghanistan in Dushanbe, Tajikistan.
O: 28APR2026 13:20:58 36.4N 71.6E MB=4.6 EMSC HINDU KUSH, AFGHANISTAN
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 28, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9570 0054 0103 0110 C2.3 (April 28, 2026) 1.9E-03
Chiapas M 4.1 01:02 UT
9580 0122 0132 0149 C2.7 (April 28, 2026) 3.9E-03
9590 0458 0506 0510 C1.6 (April 28, 2026) 1.0E-03
9650 0809 0817 0822 C6.0 (April 28, 2026) 3.4E-03
9670 0914 0923 0926 C9.0 (April 28, 2026) 3.6E-03
9680 0928 0932 0941 C7.1 (April 28, 2026) 5.7E-03
Hawaii M 3.0 09:32 UT
9710 1112 1118 1121 C3.1 (April 28, 2026) 1.5E-03
Greece M 4.7 11:12 UT
9720 1141 1146 1148 C9.3 (April 28, 2026) 2.5E-03
9790 1200 1214 1217 C7.7 (April 28, 2026) 6.1E-03
Eastern Turkey M 4.1 12:02 UT
9730 1217 1223 1229 M1.0 (April 28, 2026) 7.1E-03
9750 1349 1353 1355 M1.5 (April 28, 2026) 3.1E-03
9760 1403 1407 1409 M1.1 (April 28, 2026) 3.1E-03
9780 1430 1433 1436 C2.6 (April 28, 2026) 1.1E-03
9840 1549 1553 1555 C4.2 (April 28, 2026) 1.3E-03
9850 1601 1608 1611 C2.7 (April 28, 2026) 1.4E-03
New Mexico M 3.4 16:07 UT
Tonga M 4.9 16:18 UT
9910 1843 1849 1853 C8.1 (April 28, 2026) 4.5E-03
9940 1949 1953 1955 C2.5 (April 28, 2026) 1.1E-03
Halmahera M 4.4 19:59 UT
9970 2202 2205 2207 C3.1 (April 28, 2026) 8.5E-04
9980 2239 2247 2304 C2.0 (April 28, 2026) 2.6E-03
Samar, Philippines M 4.9 22:58 UT
Southern Texas M 2.0 23:03 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active April 29-30 unsettled May 1. Solar M-flare chance: 70% X-class: 20% proton storm: 15%
AP Indicies: global: 3, high: 1, mid-latitude: 3, time of max AP: 22:00 UT; Max AP: 2 Global Kp 1.33 1400-1700, April 28; Sunspot Number: 144; Radio Flux: 149
April 28, 2026
Notable earthquakes and events:
A strong variation in the global geomagnetic field was recorded at GOES-19 orbit on April 27 beginning
near 06:25 UT and ending about 08:00 UT. This necessitated an arcjet correction to the position of the satellite.
Areas at local solar noon at this time are in central Asia including India
and Afghanistan while those at midnight are in Central U.S. and Central America.
These areas may see enhanced seismicity following this geomagnetic excursion.
NEIC reported earthquakes of M 3.5 and M 3.3 in Northern California were felt with intensity up to II-III in the area(s) of Northern California with III in Portola, Sierra City, California and in Nevada at Silver Springs and Gardnerville with II in Reno, Blairsden-Graeagle, California at Clio, Quincy, Milford, Portola and Janesville.
O: 28APR2026 04:17:52 39.9N 120.4W ML=3.5 NEIC NORTHERN CALIFORNIA
O: 28APR2026 03:10:06 39.9N 120.4W ML=3.3 NEIC NORTHERN CALIFORNIA
O: 28APR2026 04:17:52 39.9N 120.4W ML=3.4 EMSC NORTHERN CALIFORNIA
O: 28APR2026 03:10:06 39.9N 120.4W ML=3.2 EMSC NORTHERN CALIFORNIA
O: 28APR2026 03:13:38 39.9N 120.4W MD=2.0 EMSC NORTHERN CALIFORNIA
O: 28APR2026 03:24:28 39.9N 120.4W MD=2.3 EMSC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.3 in Nevada was felt with intensity up to II-III in the area(s) of Nevada with III in Silver Springs and II in Reno and Gardnerville.
O: 28APR2026 03:57:54 39.3N 119.1W ML=3.3 NEIC NEVADA
O: 28APR2026 02:34:58 39.2N 119.1W ML=2.2 EMSC NEVADA
O: 27APR2026 13:27:45 39.3N 119.1W ML=2.1 EMSC NEVADA
O: 28APR2026 03:57:54 39.3N 119.1W ML=3.3 EMSC NEVADA
O: 28APR2026 03:58:48 39.3N 119.1W ML=3.0 EMSC NEVADA
NEIC reported an earthquake of M 4.8 in Costa Rica was felt with intensity up to II-III in the area(s) of Costa Rica with IV in Santiago, Alajuela, Cartago, La Suiza, Atenas, Copey, San Jose, San Diego, San Isidro, Sabanilla, San Ramon and III in Fortuna and Santa Ana.
EMSC reported long shaking in Costa Rica at Santa Ana, Guaalupe, San Rafael, Atenas, Naranjo. San Ramon, San Rafael, Quepos, San Isidro, La Suiza, Daniel Flores, La Fortuna, Ciudad Cortes.
O: 28APR2026 03:49:47 9.8N 84.2W ML=4.8 NEIC COSTA RICA
O: 28APR2026 03:49:48 9.9N 84.2W MB=4.8 EMSC COSTA RICA
NEIC reported an earthquake of M 4.3 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska with III in Matanuska-Susitna Borough, Palmer, Talkeetna, Anchorage and II in Wasilla, Chugiak.
O: 28APR2026 03:33:30 63.1N 149.8W MB=4.3 EMSC CENTRAL ALASKA
O: 28APR2026 03:33:31 63.1N 149.8W ML=4.3 NEIC SOUTHERN ALASKA
NEIC reported an earthquake of M 3.3 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 Wildomar, Loma Linda, Redlands, Newport Beach, Riverside, Colton, San Bernardino, Redlands, Perris and Moreno Valley.
EMSC reported moderate shaking in Redlands, Moreno Valley, Mentone, Loma Linda, Grand Terrace, March AFB. Woodcrest, Riverside, Lancaster. It was also heard in the area.
O: 27APR2026 14:47:13 34.0N 117.2W ML=3.3 NEIC GREATER LOS ANGELES, CALIFORNIA
O: 27APR2026 14:47:13 34.0N 117.2W ML=3.1 EMSC GREATER LOS ANGELES AREA, CALI
O: 27APR2026 18:11:44 34.0N 117.2W ML=2.1 EMSC GREATER LOS ANGELES AREA, CALIF.
NEIC reported an earthquake of M 4.3 in Northern Chile was felt with intensity up to II-III in the area(s) of Northern Chile in Iquique, Tarapaca.
O: 27APR2026 11:37:40 21.1S 69.1W ML=4.3 NEIC NORTHERN CHILE
O: 27APR2026 11:37:40 21.1S 69.1W MB=4.3 EMSC TARAPACA, CHILE
EMSC reported an earthquake of M 4.0 in Eastern Turkey was felt with intensity up to IV in the area(s) of Eastern Turkey at Colakli, Malatya.
O: 27APR2026 12:22:56 38.3N 38.7E ML=4.0 EMSC EASTERN TURKEY
EMSC reported an earthquake of M 4.9 in Crete was felt with intensity up to IV in the area(s) of Crete, Greece at Analipsi, Makry-Gialos, Sitia, Ierapetra.
O: 26APR2026 07:45:02 34.8N 26.1E MB=4.9 EMSC CRETE, GREECE
O: 27APR2026 07:45:02 34.8N 26.1E MB=4.9 EMSC CRETE, GREECE
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 27, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9340 0058 0105 0107 C2.7 (April 27, 2026) 2.3E-03
9310 0107 0121 0126 C3.3 (April 27, 2026) 3.9E-03
Arabian Sea M 3.8 01:09 UT
Montana M 2.6 01:07 UT
9320 0128 0137 0142 C4.6 (April 27, 2026) 3.6E-03
9350 0153 0203 0209 C6.8 (April 27, 2026) 6.3E-03
9330 0209 0215 0218 C6.5 (April 27, 2026) 4.0E-03
Chiapas M 4.1 02:13 UT
9360 0330 0337 0341 C5.9 (April 27, 2026) 3.3E-03
Montana M 3.0 03:32 UT
Utah M 2.5 03:28 UT
9370 0405 0410 0417 C3.5 (April 27, 2026) 2.7E-03
9380 0537 0543 0550 C1.8 (April 27, 2026) 1.4E-03
9390 0602 0607 0611 C1.8 (April 27, 2026) 1.0E-03
Chile M 4.3 06:09 UT
Crete M 4.1 06:13 UT
9400 0639 0645 0650 M1.0 (April 27, 2026) 4.3E-03
Afghanistan M 5.1 06:46 UT
Guatemala M 4.0 06:48 UT
9420 0738 0745 0751 C5.4 (April 27, 2026) 3.2E-03
Crete M 4.9 07:38 UT
9450 1000 1007 1011 C1.6 (April 27, 2026) 1.0E-03
9530 1837 1846 1850 C1.7 (April 27, 2026) 1.1E-03
Java M 3.9 18:46 UT
9540 2140 2144 2148 C1.0 (April 27, 2026) 5.7E-04
9550 2245 2254 2258 C1.4 (April 27, 2026) 1.1E-03
Xinjiang, China M 4.0 22:58 UT
Oaxaca M 3.7 22:52 UT
9560 2306 2313 2316 C5.4 (April 27, 2026) 2.0E-03
Xinjiang, China M 4.5 23:05 UT
Kamchatka M 4.2 23:06 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet April 28 active April 29-30. Solar M-flare chance: 70% X-class: 25% proton storm: 15%
AP Indicies: global: 7, high: 5, mid-latitude: 6, time of max AP: 00:00 UT; Max AP: 3 Global Kp 3.00 0000-0300, April 27; Sunspot Number: 122; Radio Flux: 142
April 27, 2026
Notable earthquakes and events:
A strong variation in the global geomagnetic field was recorded at GOES-19 orbit on April 27 beginning
near 06:25 UT. This necessitated an arcjet correction to the position of the satellite.
Areas at local solar noon at this time are in central Asia including India
and Afghanistan while those at midnight are in Central U.S. and Central America.
These areas may see enhanced seismicity following this geomagnetic excursion.
Other geomagnetic excursions today were recorded at GOES-18 beginning at 19:04-20:30 UT
on April 26 and at 08:40 UT. Areas most likely to see variations in seismicity
with these are in the western U.S. and on the western Pacific Ring of Fire
near 120 East longitude.
NEIC reported an earthquake of M 5.1 in Tajikistan was felt with intensity up to II-III in the area(s) of Tajikistan near Khorugh at Dushanbe.
EMSC reported moderate shaking in Baharak, Kabul, Afghanistan, in Pakistan at Dasu and Gilgit, Islamabad, Rawalpindi, in Uzbekistan at Tashkent, Yangi-Nishon Shahri; in Almaty Kazakdhstan; in India at Sringar, and in Tajikistan at Dushanbe,
The earthquake occurred within minutes of local solar noon in conjunction
with a strong geomagnetic GOES-19 signal beginning at 06:25 UT (see above)
and may have been promoted by energy associated with that.
This epicenter is at the sixth node (60 degrees) from the Molucca Sea; at the seventh
node (72 degrees) from Malaysia and at 104 degrees from Vanuatu and may have
been promoted by energy from those sources.
O: 27APR2026 06:46:08 37.3N 71.3E MB=5.1 NEIC TAJIKISTAN
O: 27APR2026 06:46:08 37.4N 71.4E MW=5.1 EMSC HINDU KUSH REGION, AFGHANISTAN
NEIC reported an earthquake of M 3.7 in Puerto Rico was felt with intensity up to II-III in the area(s) of Puerto Rico with IV in Lajas and III in Guanica.
EMSC reported possible shaking in Puerto Rico at Guaynabo, San German and Camuy.
Like the event in Tajikistan today (see above) this event was closely
associated with the geomagnetic field variation recorded as beginning
around 06:25 UT (see above) and may have been promoted by energy associated
with it.
O: 27APR2026 06:31:25 17.9N 67.0W MB=3.7 NEIC PUERTO RICO
O: 27APR2026 06:31:25 17.9N 67.0W MD=3.7 EMSC PUERTO RICO REGION
The strongest earthquake in the world today was an M 6.1 in the Hokkaido region of northern Japan. This event
occured about 300 km north of the M 7.7 off northeastern Honshu of April 20 but may
be related to it be energy redistribution in the epicentral areas. This event may
have been promoted by a strong geomagnetic excursion at the same time as
recorded on GOES magnetometers (see above). NEIC reported it was felt in Hokkaido, Japan with intensity V in Obihiro; IV in Muroran; III in Hakodate, Sapporo, Chitose, Nakashibetsu, and in Sendai, Miyagi and Aomori with lesser shaking in Chiba Prefecture.
EMSC reported shaking in Sendai, Japan.
This is the strongest earthquake in Hokkaido, Japan within about 150 km of this
epicenter since an M 6.2 on June 11, 2023. A major M 7.6 quake hit the area about 150
km south of this on December 8, 2025. At the time of the event in June, 2023
this summary noted:
"Today's earthquake of M 6.6 is the strongest in Hokkaido within about 200 km
of this epicenter since an M 6.7 on January 14, 2016 and an M 6.9 on February 2, 2013. The
only other such event in the past 15 years was an M 6.8 on September 11, 2008." (September 5, 2018, June 11, 2023)
Today's earthquake in Hokkaido may have been promoted by SFE associated with solar
Flare 9180 of M2.2 class. This flare was still in progress when the event
in Hokkaido occurred. Preliminary Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9180 1954 2004 2027 M2.2 (April 26, 2026) 9.9E-03 *
Atacama, Chile M 4.1 20:08 UT
Hokkaido, Japan M 6.1 20:23 UT
This epicenter is at the sixth node (60 degrees) from Vanuatu and at the fifth node from Tonga and
the eighth node (45 degrees) from The Molucca Sea and may have been promoted
by energy from those sources.
O: 26APR2026 20:23:55 42.6N 143.0E MB=6.1 NEIC HOKKAIDO, JAPAN
O: 26APR2026 20:23:55 42.7N 142.9E MW=6.1 EMSC HOKKAIDO, JAPAN REGION
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 with III in Bellingham and Mount Vernon and II in Anacortes, Port Ochard, Bow, Mukilteo and in British Columbia, Canata at Victoria and Walnut Grove.
O: 27APR2026 04:22:37 48.6N 122.6W MB=2.7 NEIC WASHINGTON STATE, USA
O: 27APR2026 04:22:37 48.6N 122.6W ML=2.7 EMSC SAN JUAN ISLANDS REG, WASHINGT
NEIC reported an earthquake of M 2.5 in Alabama was felt with intensity up to II-III in the area(s) of Alabama in Marietta, Georgia.
The last earthquake in Alabama within about 159 km of this epicenter with
M>=2.5 occurred as an M 2.7 on August 13, 2022. At the time this summary noted:
"An unusual earthquake of M 2.7 occurred today in northern Alabama.
NEIC reported this earthquake of M 2.7 in Alabama was felt with intensity II-III in the area(s) of Alabama in Hazel Green, Meridianville, Toney, Ardmore, New Market, Huntsville and in Tennessee at Taft, Flintville, Fayetteville.
The last earthquake in Alabama within about 100 km of this epicenter was an M 2.2
on December 11, 2021 and an M 2.6 on November 1, 2020. But today's event
at M 2.7 is the strongest in this area since an M 3.1 on May 10, 2020." (August 13, 2022)
Today's epicenter, like a minor earthquake in Mississippi two days ago, is at
the fourth node (90 degrees) from Honshu, Japan and may have been promoted by
energy from that source.
O: 27APR2026 03:54:54 34.7N 87.1W MB=2.5 NEIC ALABAMA, USA
O: 27APR2026 03:54:54 34.7N 87.1W MD=2.5 EMSC ALABAMA
NEIC reported an earthquake of M 2.9 in Montana was felt with intensity up to II-III in the area(s) of Montana in Butte and Clinton.
O: 27APR2026 03:32:34 46.0N 112.3W MB=2.9 NEIC MONTANA, USA
O: 27APR2026 03:32:34 46.0N 112.3W ML=3.0 EMSC WESTERN MONTANA
O: 26APR2026 10:46:32 46.8N 112.7W ML=2.8 EMSC WESTERN MONTANA
NEIC reported an earthquake of M 2.5 in Utah was felt with intensity up to II-III in the area(s) of Utah at Salem and Spanish Fork.
O: 27APR2026 03:28:20 39.9N 111.6W MB=2.5 NEIC UTAH, USA
O: 27APR2026 03:28:20 40.0N 111.6W ML=2.5 EMSC UTAH
NEIC reported earthquakes of M 4.4 and M 4.2 in western Iceland off southern Iceland southwest of Reykjavik near Grindavik today.
These events occurred near local solar noon and may have been promoted by
geomagnetic and/or tidal stresses which maximize near this hour. These events
are at an unusual epicenter. The last earthquakes recorded within about 150
km of these with M>=4.4 occurred on December 9, 2025 (M 5.0) and August 1, 2021
as a volcanic swarm reaching M 5.2. At the time this summary noted:
"A strong series of earthquakes also occurred today in southwestern Iceland.
This was probably promoted by energy from the Alaska Peninsula. A similar
series of events in Iceland occurred following the M 7.5 on July 22, 2020
in the Alaska Peninsula and the day after the M 7.8 on October 19, 2020.
That event was an M 5.5, slightly larger than today's maximum magnitude
in Iceland. This event occurred on October 20 and was noted in this summary as:
"This (of M 5.5) is the strongest earthquake in southern Iceland within about 200 km of
this epicenter since an M 6.3 more than 12 years ago on May 29, 2008. Other
such events occurred in 1998 and 2000. It is likely that this was triggered
by energy from the Alaska Peninsula quake of M 7.5 yesterday" (October 20, 2020, August 1, 2021)
This activity in Iceland may have been promoted by SFE from solar flares 9080 and 9250
which were in progress when the earthquakes occurred. This epicenter was
at local solar noon when flare 9040 occurred (M1.4) and may have been
set up by SFE with that flare as well. Data for these flares from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9040 1354 1403 1438 M1.4 (April 26, 2026) 7.1E-03 *
9080 1504 1511 1518 C2.7 (April 26, 2026) 2.6E-03
9250 1518 1522 1529 C2.9 (April 26, 2026) 2.1E-03
Iceland M 4.4 15:14 UT.
This epicenter is at 104 degrees from Malaysia (node 7) and may have been
promoted by energy from that source.
O: 26APR2026 15:14:14 62.6N 25.5W MB=4.4 NEIC ICELAND
O: 26APR2026 15:14:14 62.6N 25.7W mb=4.4 EMSC ICELAND REGION
O: 26APR2026 16:22:43 62.6N 25.4W MB=4.2 NEIC ICELAND
O: 26APR2026 16:22:43 62.5N 25.5W MB=4.2 EMSC ICELAND REGION
O: 27APR2026 04:00:59 63.7N 23.3W ML=2.9 EMSC ICELAND REGION
NEIC reported an earthquake of M 3.4 in Southern California was felt with intensity up to II-III in the area(s) of Southern California where it was widely felt east of Los Angeles. NEIC reported IV in California at Cabazon, III in White Water, Idyllwild, Indio, Palm Springs, Cathedral City, Rancho Mirage, Hemet, Palm Springs and Pasadena.
EMSC reported strong shaking in Palm Springs, with a rumble and in Idyllwild, Thousand Palms, Cathedral City, Anza, Palm Desert, Moreno Valley, Indian Wells, March AFB, La Quinta, Indio, San Dimas, Burbank, Lancaster.
This event in Southern California followed flares 9080 and 9250 (see above)
and may have been promoted by energy associated with those solar flares.
O: 26APR2026 15:44:34 34.0N 116.8W MB=3.4 NEIC SOUTHERN CALIFORNIA
O: 26APR2026 15:44:33 34.0N 116.8W ML=3.3 EMSC SOUTHERN CALIFORNIA
O: 26APR2026 15:17:37 34.0N 116.8W ML=2.3 EMSC SOUTHERN CALIFORNIA
O: 26APR2026 15:45:22 34.0N 116.7W ML=2.1 EMSC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 2.9 in Michigan was felt with intensity up to II-III in the area(s) of Michigan with III in Detroit, South Rockwood, Grosse Ile, Carleton, Rockwood, Trenton, Erie, Flat Rock, Monroe, Detroit. It was also felt in large portions of Southern Ontario, Canada.
EMSC reported shaking and noise in Michigan rolling across Lake Erie at Rockwood, Grosse Ile, and Monroe.
The last earthquake within about 150 km of this epicenter in Michigan with
M>=2.9 occurred as an M 3.2 on August 21, 2020. At the time this summary noted:
"An unusual earthquake of M 3.2 was widely felt in the area south of Detroit, Michigan today. NEIC reported maximum intensit IV in Michigan at Monroe, Luna Pier, South Rockwood and II-III in Newport, La Salle, Carleeton, Rockwood, Erie, Flat Rock. The earthquake was felt with light intensity as far as Ohio, Pennsylvania, Wisconsin, Illinois, New Jersey, New York, Tennessee, North Carolina, Massachusetts, Georgia, Connectict and Missouri among other states in the eastern U.S.
No major damage was reported. The last earthquake in the Detroit area occurred
as an M 3.4 on April 20, 2018. The largest regional earthquake in the past
30 years was an M 4.2 on May 2, 2015. An M 2.0 also occurred when a meteor hit the earth near Detroit on January 16, 2018. Other recent
quakes occurred as an M 4.0 near Kalamazoo on May 2, 2015. Today's earthquake
did not affect operations at the area's two nuclear power plant.
When the M 4.2 occurred in May, 2015 this summary noted:
"The last earthquake within about 200 km of this epicenter with M>=4.2 occurred
on August 10, 1947 with M 4.7. Other recent earthquakes in the area occurred
on February 4, 1883 and February 4, 1833 (may be an error in the year).
The earthquake in 1883 was felt in northern Indiana and southern Michigan in Kalamazoo, Michigan.
Windows were cracked and chimneys damaged in Kalamazoo. It was felt as far as
St. Louis, Missouri and in Bloomington, Illinois. The earthquake in 1947 was also
located near the epicenter of today's event. It was felt through southern Michigan where
damage was reported. It was also felt with intensity up to VI in Illinois, Michigan, Indiana
and Wisconsin. Damage included cracked plaster, with windows and items thrown down from store shelves." (May 3, 2015, August 21, 2020)
Today's event in Michigan occurred in the local solar morning and was
closely associated with a strong C8.4 solar flare which maximized within
minutes of this earthquake and/or flare 8040 - an M1.4 flare which was still
in progress when the event in Michigan occurred. SFE from this flare may have helped promote
this event in Michigan. Following are preliminary data for this flare from SWPC:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9040 1354 1403 1438 M1.4 (April 26, 2026) 7.1E-03 *
9050 1418 1425 1433 C8.4 (April 26, 2026) 6.2E-03
Michiagn M 2.9 14:32 UT
Like the event in Alabama today (see above) this epicenter is at the fourth node
(90 degrees) from Honshu, Japan and may have been promoted by energy from that source.
O: 26APR2026 14:32:03 42.0N 83.0W MB=2.9 NEIC MICHIGAN, USA
O: 26APR2026 14:32:03 42.0N 83.1W ML=2.9 EMSC MICHIGAN
NEIC reported an earthquake of M 2.7 in Central California was felt with intensity up to II-III in the area(s) of Central California south of San Francisco with III in San Jose and II in San Ramon.
O: 26APR2026 10:27:11 37.3N 121.7W MB=2.7 NEIC CENTRAL CALIFORNIA, USA
O: 26APR2026 10:27:11 37.3N 121.6W MD=2.6 EMSC NORTHERN CALIFORNIA
The strongest earthquake in the U.S. or Canada today was an M 4.3 in the
Beaufort Sea of northern Alaska. It was not reported felt in this remote area.
This is the strongest earthquake in the Beaufort Sea area of Alaska within
about 200 km of this epicenter since an M 5.3 on October 25, 2025 and is
probably an aftershock of that event. At the time this summary discussed
this as:
"The strongest earthquake in the U.S. or Canada today was an M 5.3 in the Beaufort Sea area of northern Alaska near the Yukon, Canada border.
It was not reported felt in this remote area. It appears to be the strongest
earthquake in this area of Alaska within about 200 km in at least 35 years.
The last earthquake in the Beaufort Sea area of Alaska with M>=5 within about 200 km occurred as an M 5.1 on
March 30, 2021, the only other such event in the region in the past 35 years. At
the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.1-5.3 in the Beaufort Sea
in the Yukon and Nunavut, Canada. It was not reported felt in this remote area.
This is the strongest earthquake in the Beaufort Sea within about 300 km of
this epicenter in at least 30 years. The largest earthquake previously recorded
in this area was an M 6.5 on November 16, 1920. Other earthquakes in the area
of M>5.1 hit the area on July 5, 1937 (M 5.5); and March 30, 1987 (M 5.2-5.5) exactly 34 years ago today.
An M 5.1 also hit the area on June 14, 1975." (March 30, 2021, October 25, 2025)
This epicenter is at the seventh node (51 degrees) from Honshu, Japan and
near the fourth node (90 degrees) from the other major earthquakes in the
world in the past four months - in Tonga, Malaysia, Vanuatu andthe Molucca
Sea and may have been promoted by constructive interference of energy from
those sources.
It may also have been promoted by a strong M6.0 solar flare - (#9210 M6.0)
as it occurred towards the end of that flare near local solar noon. Data
from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9210 2251 2257 2322 M6.0 (April 26, 2026) 2.2E-02 *
Beaufort Sea, Alaska M 4.3 23:12
O: 26APR2026 23:12:53 71.2N 133.7W ML=4.3 EMSC BEAUFORT SEA
EMSC reported an earthquake of M 4.9 in Crete was felt with intensity up to IV in the area(s) of Crete, Greece at Analipsi, Makry-Gialos, Sitia, Ierapetra.
O: 26APR2026 07:45:02 34.8N 26.1E MB=4.9 EMSC CRETE, GREECE
O: 27APR2026 07:45:02 34.8N 26.1E MB=4.9 EMSC CRETE, GREECE
O: 26APR2026 18:40:20 34.9N 25.9E ML=4.0 EMSC CRETE, GREECE
GeoNet reported an M 4.2-4.4 earthquake in North Island, New Zealand was widely
felt today. Following are the parameters for this quake from GeoNet.
O: 26APR2026 16:07:52 40.1S 176.3E ML=4.4 GEONET Felt with moderate to light intensity in the area southeast of Wellington, New Zealand and in southern North Island and northern South Island. 366 reports of felt events were made of which 169 reported weak and 161 light intensity with 35 reports of moderate shaking and 1 with strong and 0 severe and 0 with extreme intensity came from the area.
O: 27APR2026 09:55:19 41.1S 173.6E ML=3.9 GEONET 2819 people reported feeling this earthquake near Seddon, New Zealand with 1947 at weak intensity and 815 with light shaking and 53 with moderate intensity 2 with strong, 1 with severe and 1 with extreme intensity.
This earthquake may have been promoted by solar flares 9110 and 9270 as it
occurs at the end of the first and the beginning of the second. Data on these
flares from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
9110 1549 1601 1607 C5.0 (April 26, 2026) 4.9E-03
9270 1607 1613 1619 C4.9 (April 26, 2026) 3.8E-03
North Island, New Zealand M 4.2 16:07 UT
This epicenter is at the sixth node (60 degrees) from the Molucca Sea and
at the fifth node (72 degrees) from Malaysia and may have been promoted
by energy from those sources.
O: 26APR2026 16:07:52 40.1S 176.3E MB=4.2 EMSC NORTH ISLAND OF NEW ZEALAND
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 26, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8850 0008 0023 0035 M1.3 (April 26, 2026) 1.2E-02
Egypt M 4.3 00:13 UT
8930 0519 0526 0531 C2.1 (April 26, 2026) 1.6E-03
8950 0708 0719 0726 C3.8 (April 26, 2026) 2.9E-03
Norway M 3.9 07:24 UT
Molucca Sea M 5.0 07:20 UT
8970 0907 0912 0921 C1.2 (April 26, 2026) 1.1E-03
8990 1104 1117 1126 C3.5 (April 26, 2026) 3.5E-03
9000 1132 1136 1140 C3.6 (April 26, 2026) 1.6E-03
9240 1218 1222 1231 C1.9 (April 26, 2026) 1.9E-03
9020 1231 1237 1241 C2.5 (April 26, 2026) 1.6E-03
9040 1354 1403 1418 M1.4 (April 26, 2026) 7.1E-03
Kuril Is. M 4.4 14:15 UT
9050 1418 1425 1433 C8.4 (April 26, 2026) 6.2E-03
Michigan M 2.9 14:32 UT
9080 1504 1511 1518 C2.7 (April 26, 2026) 2.6E-03
9250 1518 1522 1529 C2.9 (April 26, 2026) 2.1E-03
Iceland M 4.4 15:14 UT.
Southern California M 3.4 15:44 UT
9110 1549 1601 1607 C5.0 (April 26, 2026) 4.9E-03
9270 1607 1613 1619 C4.9 (April 26, 2026) 3.8E-03
North Island, New Zealand M 4.2 16:07 UT
9140 1734 1739 1742 C5.4 (April 26, 2026) 2.2E-03
9150 1757 1803 1809 C9.7 (April 26, 2026) 5.5E-03
9160 1900 1915 1918 C8.8 (April 26, 2026) 9.9E-03
9220 1918 1924 1927 M1.7 (April 26, 2026) 8.4E-03
Central Peru M 4.0 19:23 UT
Xizang M 4.2 19:26 UT
9180 1954 2004 2027 M2.2 (April 26, 2026) 9.9E-03 *
Atacama, Chile M 4.1 20:08 UT
Hokkaido, Japan M 6.1 20:23 UT
9190 2130 2135 2137 C4.9 (April 26, 2026) 2.4E-03
9200 2139 2148 2154 C7.7 (April 26, 2026) 5.8E-03
Sumatra M 3.2 21:41 UT
9280 2243 2248 2251 C5.4 (April 26, 2026) 4.3E-03
9210 2251 2257 2322 M6.0 (April 26, 2026) 2.2E-02 *
Beaufort Sea, Alaska M 4.3 23:12
Yukon M 3.7 23:10 UT
Honshu, M 3.2 22:45 UT
Argentina M 3.9 23:14 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active April 27 unsettled April 28-29. Solar M-flare chance: 55% X-class: 15% proton storm: 10%
AP Indicies: global: 14, high: 18, mid-latitude: 13, time of max AP: 10:00 UT; Max AP: 6 Global Kp 3.67 1000-1200, April 26; Sunspot Number: 137; Radio Flux: 156
April 26, 2026
Notable earthquakes and events:
A flare near 08:00 UT on April 25 was accompanied by an M 3.3 in northern California within about a minute
of local solar midnight and an M 5.4 in the Unimak Island area of Alaska near local
solar midnight in that area several minutes after the M 3.2 in northern California.
These events area likely to have been triggered by SFE with this flare. Areas at local solar
noon with the second X-class flare are near 60E and those at midnight are near 120 W and include
active areas of California, Nevada and the western U.S. and Iran, Pakistan and
Afghanistan in the east. Moderate to strong earthquakes could occur in these
areas in the hours following these flares. Residents may take notice. These are the strongest solar flare cataloged by SWPC since an
X2.7 on May 14, 2025 (SWPC# 3410) nearly a year ago. CME from the two X-class
flares today have been observed and could hit the earth environment in several
days - about April 26-28. They could also help trigger geomagnetic storms which
may promote seismicity when they commence. A strong geomagnetic variation occurred on GOES magnetometers
beginning about 23:40 UT on April 24 and lasting through 01:20 UT on April 25.
An arcjet adjustment was required to adjust orbit on the GOES-19 satellite
beginning at about 23:47 on April 24. Seismicity at longitudes near the
International Date Line (180 degrees E/W) are most likely to be affected
by this geomagnetic excursion. A geomagnetic storm commenced with drastic reductions
in Electron Flux at GOES Satellite atltitudes and lasted through this writing
at about 09:00 UT. A slight elevation in proton count was also observed at this
time. A strong geomagnetic field variation was also observed on the GOES
magnetometers starting around 04:20 UT on May 26. This occurred at the
minimum of the strength of the geomagnetic field. This could enhance seismicity
near 80-100 East longitude (Central Asia) which was near local solar noon
at the time of this excursion.
The strongest earthquake in the world today occurred in Mongolia with M 5.8-5.9
at the time of the geomagnetic excursion (and moderate geomagnetic storm)
as noted above starting about 04:20 UT. NEIC reported it was likely felt with
intensity VIII in the epicentral area and was reported with intensity III in Altay, Xinjiang, China
more than 350 away while EMSC reported moderate shaking in Altanteel, Mongolia. This is the strongest earthquake in Mongolia within about
250 km of this epicenter in more than 35 years.
This earthquake in Mongolia followed an M 4.7 in Siberia about 550 km northwest
of this epicenter in the area of Siberia, Russia. NEIC reported this earthquake was
felt in Siberia with intensity II in Teeli and Borovoy, Kemerovo, Russia.
The last earthquake in this area of Siberia with about 200 km with M>=4.7
occurred as an M 5.0 on May 25, 2025.
Despite the rarity of this event, this summary had expected a moderately
large earthquake in Mongolia near this epicenter to occur in late April, 2026.
The forecast (#181262) for this was published in this summary in mid-April and read as:
P: 19APR2026 181262 46.0N 96.0E 4.0-5.7 CABAA Mongolia
The epicenter in Mongolia is at the 10th node (36 degrees) from Honshu, Japan; at 103 degrees
from Tonga; the eighth node (45 degrees) from Malaysia and the fourth node (90 degrees)
from Vanuatu and was probably promoted by constructive energy interference from
those sources. The epicenter in Siberia is exactly 120.0 degrees (node 3)
from the South Geomagnetic Pole.
O: 26APR2026 04:23:24 46.8N 93.0E MB=5.9 NEIC MONGOLIA
O: 26APR2026 04:23:24 46.9N 93.0E MB=5.8 EMSC WESTERN MONGOLIA
O: 26APR2026 04:27:33 46.9N 93.1E ML=4.3 EMSC WESTERN MONGOLIA
O: 26APR2026 04:30:14 46.9N 93.1E ML=4.0 EMSC WESTERN MONGOLIA
O: 25APR2026 09:40:38 51.2N 89.8E MB=4.7 NEIC SIBERIA, RUSSUA
O: 25APR2026 09:40:38 51.3N 89.8E MB=4.8 EMSC SOUTHWESTERN SIBERIA, RUSSIA
A pair of light earthquakes of M 2.7 and M 2.9-3.0 were widely felt in the
area of San Francisco, California near the San Francisco Zoo today. NEIC
reported they were felt (with more than 1000 people reporting felt reports to NEIC) with intensity up to III in
Pinole, San Mateo, Daly City, San Anselmo, San Francisco, California.
The last earthquake within the city of San Francisco with M>=3.0 occurred as
an M 2.9 on December 8, 2025. A larger event of M 3.5 hit near this epicenter
on January 10, 2025. At the time this summary noted:
"Earthquakes of M 2.9 and M 3.6, M 2.5, off central California near San Francisco were felt in the San Francisco area today. Several were widely felt with maximum intensity IV in San Francisco; III in Burlingame, Portola Valley, Sunnyvale, San Mateo, Elk Cerrito, Oakland and II in Brisbane, Daly City, Half Moon Bay, Millbrae, Pacifica, Redwood City, San Bruno, Alameda, Albany, Richmond, among others.
EMSC reported these events were felt in San Francisco, San Mateo, Oakland, San Bruno, Pacifica. as a short thud.
The event of M 3.4-3.6 off shore San Francisco is the strongest recorded within
about 50 km of this epicenter since an M 3.7 on October 28, 2023. At the time
this summary noted:
"A light M 2.9 in Northern California south of the San Francisco Bay area occurred
following the M 5.1 in SE Alaska and may have been triggered by it. The California
quake was reported by NEIC to have been felt with intensity II-III in San Jose, Santa Clara, Los Gatos, Mountain View, Boulder Creek, Walnut Creek and San Francisco.
This activity occurred during a minor geomagnetic storm in conjunction
with the full moon and lunar eclipse today and was probably promoted by
stresses associated with those two factors. The last earthquake in San Francisco
of similar size was an M 3.6 on December 17, 2022. At the time this summary noted:
"Today's event of M 3.6 is the strongest within the San Francisco Bay area of
California within about 50 km of this epicenter since an M M 4.1 on June 2, 2022 and
prior to that an M 3.9 on June 20, 2021 and an M 4.5 on October 15, 2019.
At the time of the last such event on June 2, 2022, this summary noted:
"An earthquake of M 4.2 also shook the region of San Francisco, California today.
NEIC reported maximum intensity IV in Sulsun City with intensity III throughout most
of the rest of the San Francisco Bay area including at Concord, Benicia, Pittsburg, Birds Landing, and Pleasant Hill among others.
This is the strongest earthquake in the San Francisco Bay area of California
since an M 4.5 on October 15, 2019 and prior to that events of M 4.2-4.3
on July 16, 2019 and January 4, 2018. The last earthquake of significantly
larger magnitude in the San Francisco Bay area was an M 6.0 in the Napa area on August 24, 2014.
These are the only events of M>=4.2 in the San Francisco area in the past 13 years." (December 17, 2022, June 2, 2022, October 28, 2023, January 10, 2025)
These events appear to have occurred on the San Andreas Fault in San Francisco.
This could indicate a weakness at this epicenter where a larger event
could be triggered with a subsequent major solar flare. This epicenter was
at local solar midnight when the X2.5 flare occurred on May 25 near 08:00 UT
and effects from this flare could have helped trigger today's earthquakes
in San Francisco.
They were also closely associated with a C1.9 solar flare (#8840) which
began at the same time as these earthquakes. Preliminary data for this
flare from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8840 2340 2348 2355 C1.9 (April 25, 2026) 1.3E-03
Offshore Northern California M 2.7, 2.9 23:40 UT 23:42 UT
Iceland M 2.9 23:44 UT
Egypt M 4.3 00:13 UT
These event occurred with the geomagnetic variation noted above beginning at 23:40 UT
on April 24.
Today's epicenters are near the fifth node (72 degrees) from Honshu, Japan and at 105 degrees
from the Molucca Sea and may have been promoted by energy from those sources.
O: 25APR2026 23:39:38 37.7N 122.5W MD=2.8 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 25APR2026 23:39:38 37.7N 122.5W MB=3.0 NEIC SAN FRANCISCO, CALIFORNIA
O: 25APR2026 23:41:56 37.7N 122.5W MD=2.7 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 25APR2026 23:41:56 37.7N 122.5W MB=2.7 NEIC SAN FRANCISCO, CALIFORNIA
An earthquake of M 4.9 also occurred in the Kermadec Islands about four minutes
before the events in San Francisco. It was not reported felt in that remote
area. The Kermadec event occurred within a couple of minutes of local solar
noon and was probably triggered by strong tidal and/or geomagnetic effects
(see above).
This epicenter in the Kermadec Islands is at the fifth node (72 degrees) from Malaysia
and at the sixth node (60 degrees) from the Molucca Sea and was likely
promoted by energy from those sources.
O: 25APR2026 23:35:19 30.3S 177.9W MB=4.9 NEIC KERMADEC ISLANDS, NEW ZEALAND
O: 25APR2026 23:35:19 30.3S 177.9W MB=4.9 EMSC KERMADEC ISLANDS, NEW ZEALAND
NEIC reported an earthquake of M 3.9 in Norway was felt with intensity up to II-III in the area(s) of Norway with IV in Auli, and Raholt, Akershus and III in Oslo, Loken, Drammen, Buskerud, Neskollen, Arnes, Askim, Ostfold, Blakstad Aust-Agder, Nesoddtangen and Stokke, Vestfold.
EMSC reported it was felt with moderate intensity in Norway at Jessheim, Ullensaker, Nordkisa, Ullensaker, Teigebyen, Neskollen, Sesvoll, Klofta, Ask, Klofta, Arnes among others and as far as Kahog and Goteborg, Sweden 275 km from the epicenter. In Arvika, Sweden a loud bang accompanied virbations from the Oslo direction and it was felt for nearly two minutes.
More than 1500 people reported felt data on this earthquake to EMSC.
The only earthquake in the past 35 years in the area with M>=3.9 occurred
on September 15, 2014 about 250 km northeast of today's epicenter. At the time
this summary noted:
" ... major earthquake triggering expected at this time - triggering
from the strong X-flare and resulting geomagnetic storm
...
Editor's note - the flare in question occurred as an X1.6 on September 10, 2014 (SWPC #5030).
and was reported in this summary as:
"A strong X1.6 class solar flare occurred late on September 10 beginning at 1659 UT and
maximizing at about 1745 UT. This major flare is the first X-class flare since three on June 10 and 11, 2014 and is the
third largest flare during 2014 after events of X4.9 on February 25 and X2.2 on June 10, 2014. A proton storm
followed this flare. A global seismic watch is being called for the period September 12-16 ..." (September 10, 2014)
The most unusual earthquake of the day occurred as an M 4.7 in Sweden. This continues
the increase of seismicity at high latitudes related to the concluded geomagnetic
storm of the past four days. NEIC reported this event was felt with intensity II=III
in Sweden in Bollnas, Gavle, Hudiksvall, Sandviken, Stockholm, and Sundsvall and In
Norway at Oslo, Koppang and Rena in the regions of Buskerud and Hedmark.
EMSC reported moderate shaking in Alvdalen, Skattungbyn, Leksand, Delsbo, Svardsjo, Falun, Borlange, Sandviken, Gavle, Skutskar, Alvkarleby, Solleftea, Ornskoldsvik, Nykoping, Linkoping, Bjurholm, Sweden and in Norway at Trondheim, Valer and Engerdal, Local seismologists revealed this was the strongest earthquake in Sweden in
more than a century. The epicenter was between the towns of Mora and Sveg and was accompanied
by a loud earthquake noise. Many people reported falling objects with the earthquake, hte
largest in Sweden according to the Uppsala University staff since an M 5.5 in the Koster Islands
in 1903. Tremors were reported as far away as Finland. NEIC reported an M 5.1
about 400 km to the west of this on August 4, 2003 and an M 4.7 700 km to the southwest
on November 8, 1992, the only events in the general area of M>=4.7 in the past 25 years.'( September 14, 2014)
In light of this flare and Norwegian/Swedish earthquake in 2014, the coincidence of today's M 3.9 in Norway
can be better seen in a historical context.
This earthquake in Norway, like that in San Francisco today (see above)
is at the fifth node (72 degrees) from the M 7.7 in Honshu, Japan of April 20. It is
also at 101 degrees from the Molucca Sea and may have been promoted by
energy from those sources.
O: 26APR2026 07:24:54 60.0N 11.5E MB=3.9 NEIC NORWAY
The M 3.9 in Norway today was not the only unusual earthquake in Europe today.
After a strong series of light earthquakes, an M 4.2 occurred near Walenstadt, Switzerland
today. EMSC reported short shaking in Switzerland at Buchs, Flums, Sargans, Haag, Rheintal, Bad Ragaz, in Austria at Feldkirch and Lustenau and in Liechtenstein at Balzers, Schaan, Vaduz. This is at nearly the same longitude as the event in Norway. NEIC reported it was felt with intensity IVin Liechtenstein at Triesen and Schaan; III in Switzerland in Sankt Gallen at Quarten and Sargans and in Baden-Wurttemberg, Germany at Fridrichshaften.
This is the largest earthquake in Switzerland within about 200 km of today's
epicenter since an M4.2 on June 27, 2024 about 200 km northwest of this epicenter.
The lst event of significantly larger magnitude in this area of Switzerland was an M 4.6
on October 25, 2020 of M 4.5. At the time this summary noted:
"An unusual M 4.3-4.5 was widely felt in eastern Switzerland today. It was followed by a number of smaller aftershocks. NEIC reported the mainshock was felt with maximum intensity IV in Switzerland at Glarus and Nafels and III in Ennenda, Filzbach, Linthal, Sargana, Braunwald, Flims, Bad Ragaz and Wartau among others.
The last earthquake in Switzerland with M>=4.3 was an M 4.5 more than ten years
ago on January 4, 2009 and prior to that an M 4.4 on November 12, 2005." (October 25, 2020).
This epicenter is at 107 degrees from the Molucca Sea event of April 1
and joins other earthquakes in Europe in Norway and Italy today at this distance from
the Molucca Sea. It is likely these events were promoted by energy from that source.
O: 26APR2026 02:24:03 47.2N 9.3E MB=4.2 NEIC SWITZERLAND
O: 26APR2026 02:24:04 47.1N 9.4E ML=3.9 EMSC SWITZERLAND
A third European earthquake near the longitude of the events in Switzerland a
and Norway occurred in southern Italy north of Sicily today near Ciittadella del Capo.
This earthquake occurred near local solar noon and was probably triggered
by tidal and/or geomagnetic effects which maximize near this hour. This Italian
earthquake is at a somewhat unusual intermediate depth of 272 km where earthquakes
of this size are uncommon. The last earthquake in this area within about 100
km of today's epicenter occurred as an M 5.1 on February 7, 2025. At the time
this summary noted:
"An earthquake of M 5.1 also occurred in Sicily, Italy today and was followed by
a series of minor aftershocks. This earthquake in Sicily is the strongest
withing about 200 km of this epicenter since an M 5.2 on May 1, 2023. At the time
this summary noted:
"An M 5.2 earthquake north of Sicily, Italy today was felt with intensity I in Bonifati, Calabria, Italy.
The last earthquake within about 150 km of this epicenter with M>=5.2 in Italy
occurred on October 31, 2022 with M 5.5 and before that on October 28, 2016 with M 5.8.
Earthquakes in this area occur at intermediate to deep focal depths (250-500 km)
and have little effect on surface features. The October 31, 2022 was, like today's
event associated about a week after a solar eclipse on October 25 as noted
in this summary at the time:
"A moderately strong earthquake occurred at intermediate depth in southern Italy today with M 5.5. It was reported by NEIC to have been felt with intensity III in Platania, Calabria, Italy.
This event was likely promoted by tidal stresses which maximized at this longitude (15E)
with the solar eclipse and new moon of October 25 ..." (February 7, 2025)
The epicenters of the earthquakes in Europe in Norway, Switzerland and Italy today were
within minutes of the beginning of solar flare #5000 of X2.5 on April 24 and
an M1.4 flare at the end of April 25. Preliminary Data on this flare from SWPC follow.
This event is at 105 degrees from the Molucca Sea, similar to the other
unusual events in Europe today and was likely promoted by energy from that source.
O: 25APR2026 11:43:02 39.4N 15.4E MB=4.0 NEIC SOUTHERN ITALY
O: 25APR2026 11:43:01 39.3N 15.5E MB=4.0 EMSC SOUTHERN ITALY
NEIC reported earthquake of M 3.3 and M 3.8 in Nevada were felt with intensity up to II-III in the area(s) of Nevada with III in Falon and II in Silver Springs, Fernley, Dayton and Gardnerville.
Like the unusual series of earthquakes in Europe today, this epicenter is
at 108 degrees from the Molucca Sea and is also at the fifth node (72 degrees)
from Honshu, Japan and was probably promoted by energy from those sources.
O: 26APR2026 07:15:21 39.4N 119.0W MB=3.3 NEIC NEVADA
O: 26APR2026 07:15:21 39.3N 119.0W ML=3.2 EMSC NEVADA
O: 25APR2026 12:11:01 39.3N 119.0W ML=3.7 EMSC NEVADA
O: 25APR2026 12:11:01 39.3N 119.0W MB=3.8 NEIC NEVADA
NEIC reported an earthquake of M 4.6 in Unimak Island, Alaska was felt with intensity up to II-III in the area(s) of Unimak Island, Alaska in Akutan.
This is an aftershock of an M 5.4-5.6 earlier in the day. In the previous
issue of this summary that event had been discussed as:
"The strongest earthquake in the U.S. or Canada today was an M 5.6 in the Unimak Island area of Alaska. This epicenter
continues a westward migration of major aftershocks from the mainshock of M 7.8 on July 22, 2020 in the Alaska Peninsula.
Further strong seismicity in this migration is likely. The only event of M>=4.5
in the Unimak Island area in the past year was an M 4.7 on May 9, 2020. The only
events of equal or larger magnitude in the Unimak area of Alaska in the past
10 years occurred with M 5.7-5.8 on November 6, 2011 and October 27, 2016." (August 13, 2020)
This activity in the Unimak Island area occurred near the peak output of an M1.3
Solar flare and was probably promoted by energy associated with this flare.
Preliminary data for this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8510 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
Crete M 3.5 07:59 UT
Northern California M 3.3 08:00 UT
Banda Sea M 3.9 08:04 UT
Unimak Island M 5.4 08:05 UT
This epicenter is at the tenth node (36 degrees) from Honshu, Japan and at
the fifth node (72 degrees) from Tonga and Vanuatu and may have been promoted
by constructive energy interference from those sources." (April 25, 2026)
O: 25APR2026 08:14:29 53.5N 164.8W ML=3.0 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:26:39 53.5N 164.8W ML=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:30:33 53.5N 164.9W ML=3.3 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:42:13 53.5N 164.8W ML=3.2 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:43:44 53.5N 164.7W ML=3.9 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 10:03:37 53.5N 164.7W ML=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:05:55 53.6N 164.9W Mw=5.4 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:11:09 53.6N 164.8W ML=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 11:19:40 53.6N 164.9W ML=3.3 EMSC UNIMAK ISLAND REGION, ALASKA
O: 26APR2026 03:31:11 53.6N 164.8W ML=3.9 EMSC UNIMAK ISLAND REGION, ALASKA
O: 26APR2026 04:26:59 53.7N 164.8W mb=4.6 EMSC UNIMAK ISLAND REGION, ALASKA
NEIC reported an earthquake of M 4.5 in the Rat Islands, Alaska was felt with intensity up to II-III in the area(s) of the Rat Islands, Alaska in Attu Station.
O: 26APR2026 03:28:29 52.2N 176.3W MB=4.5 NEIC RAT ISLANDS, ALASKA
O: 26APR2026 03:28:29 52.2N 176.4E MB=4.5 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 25APR2026 15:41:10 52.1N 176.4E ML=4.1 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 25APR2026 16:47:05 51.6N 178.3E ML=3.8 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
NEIC reported an earthquake of M 3.4 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska with II in Karluk.
O: 26APR2026 02:54:06 57.6N 155.5W MB=3.4 NEIC SOUTHERN ALASKA
O: 26APR2026 02:54:06 57.6N 155.6W ML=3.4 EMSC ALASKA PENINSULA
NEIC reported an earthquake of M 5.0 in Central Peru was felt with intensity up to II-III in the area(s) of Central Peru in Lima at San Luis and Santa Maria.
This earthquake may have been promoted by solar flare 8550 as it occurred
at the peak output of that flare. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8550 0947 0954 0956 C3.2 (April 25, 2026) 1.3E-03
Central Peru M 4.6 09:53 UT
O: 25APR2026 20:14:39 14.5S 76.5W MB=5.0 NEIC SOUTHERN PERU
O: 25APR2026 20:14:41 14.4S 76.3W MB=5.0 EMSC NEAR COAST OF CENTRAL PERU
NEIC reported an aftershock of M 4.9 in Crete, Greece was felt with intensity up to II-III in the area(s) of Aghios Nikolaos, Nisia Aigaiou, Crete and in Skhisma, Lasithi, Greece.
This is an aftershock of the M 5.8 in Crete yesterday. Many of the larger
aftershocks of that event have been closely associated with moderate to
strong solar flares.
O: 25APR2026 19:49:58 35.1N 25.9E MB=4.9 NEIC CRETE, GREECE
O: 25APR2026 19:49:57 34.9N 26.0E ML=4.8 EMSC CRETE, GREECE
NEIC reported an earthquake of M 4.2 off the coast of Oregon was not felt.
The last earthquake off the coast of Oregon within abouot 100 km of this epicenter with M>=4.2
occurred on December 20, 2025 with M 4.3 but the last of significantly
larger magnitude was an M 5.4 on October 29, 2025. At the time this summary noted:
" M 5.4 in North America today occurred off the coast of Oregon and
was accompanied by a foreshock of M 4.8 eighteeen minutes earlier. NEIC reported
these events were lightly felt along the coast of Oregon and California with intensity up
to II in Oregon at Beaverton, Klamath Falls, Hillsboro, Bandon, Rockaway Beach, Coos Bay, Willamina, and in Victoria, British Columbia, Canada and in California at Crescent City and Unioin City.
This activity occurred along the interface between the North American and Pacific Plates. The last earthquake of M>=5.4
within about 150 km of this epicenter was an M 5.6 on June 15, 2022 but the
last of significantly larger magnitude was an M 5.8 with moderate aftershocks
and foreshocks on December 8, 2021. At the time this summary noted:
"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 7-8, 2021)
Both the earthquakes in Iceland and off the coast of Oregon today occurred
with a geomagnetic storm which reached K-index of 6 at high latitudes at
the time of these earthquakes and may have contributed to their timing." (October 29, 2025)
Today's event occurred near local solar noon and may have been promoted by tidal and/or geomagnetic effects
which maximize near this hour. It occurred near the start of solar flare 8770
and may have been promoted by SFE from that source. Data from SWPC for this
flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8770 1924 1938 1953 C3.9 (April 25, 2026) 4.4E-03
Papua M 4.1 19:42 UT
Coast of Oregon 19:21 UT
This epicenter is at the sixth node (60 degrees) from Honshu, Japan and 102
degrees from Malaysia and may have been promoted by energy from those sources.
O: 25APR2026 19:20:40 44.4N 129.5W MB=4.2 NEIC OFF THE COAST OF OREGON
O: 25APR2026 19:20:40 44.4N 129.5W MB=4.2 EMSC OFF COAST OF OREGON
Moderate aftershock continued in the area of Kamchatka today. The largest
of today's events was an M 5.2 which NEIC reported was lightly felt in Russia at Vilyuchinsk and Petropavlosk-Kamchatsky. These continue
Two events in the series today - both of M 4.5 occurred within several minutes
of local solar midnight in Kamchatka and were likely promoted by solar flare 8630 which
(C3.8) reached its maximum output with these earthquakes. Data from SWPC
for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
8630 1312 1320 1328 C3.8 (April 25, 2026) 2.9E-03
Mindanao M 4.1 13:19 UT
Kamchatka M 4.5 13:22 UT M 4.5 13:23 UT
Chiapas M 4.2 13:27 UT
This series began shortly after an X2.5 solar flare which occurred
when Kamchatka was at local solar noon and peaked about 01:07 UT on April 24.
This was discussed in the previous issue of this summary as:
"Several moderately strong earthquakes also occurred in Kamchatka, Russia today.
The strongest of these was an M 5.4 which was felt with moderate intensity
at Petropavlovsk-Kamchatsky with NEIC intensity up to IV. Kamchatka experienced
a number of major earthquakes in late 2025 but has been relatively quiet
during the first several months of 2026 to date. The last earthquake of M>=5.4
in Kamchatka was recorded as an M 5.9 on March 8, 2026. But the last such event within
about 200 km of today's epicenters was an M 5.5 on January 10, 2026. A stronog
M 6.0 hit the area on November 3, 2025...."(April 25, 2026)
These epicenters are at the sixth node (60 degrees) from the Molucca Sea and
Malaysia and at the fifth node (72 degrees) from Tonga and may have been
promoted by energy from those sources.
O: 25APR2026 10:20:21 52.7N 158.7E MB=5.2 NEIC KAMCHATKA, RUSSIA
O: 25APR2026 10:20:19 52.7N 158.7E MW=5.2 EMSC NEAR EAST COAST OF KAMCHATKA
O: 25APR2026 13:22:06 52.9N 160.7E MB=4.5 NEIC KAMCHATKA, RUSSIA
O: 25APR2026 13:22:06 52.9N 160.8E MB=4.5 EMSC OFF EAST COAST OF KAMCHATKA
O: 25APR2026 13:23:32 52.9N 161.1E mb=4.5 EMSC OFF EAST COAST OF KAMCHATKA
O: 25APR2026 13:23:32 52.9N 161.0E MB=4.5 NEIC KAMCHATKA, RUSSIA
EMSC reported an earthquake of M 4.3 in Egypt was felt with intensity up to IV in the area(s) of Egypt at El-Tor, New Cairo, Kawm Hamadah.
This epicenter is at the fourth node (90 degrees) from the Molucca Sea
and may have been promoted by energy from that source.
O: 26APR2026 00:13:34 29.0N 33.4E MB=4.3 EMSC EGYPT
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 25, 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 when a flare occurred 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 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
Unimak Is. Alaska M 5.4 08:05 UT M 3.5 08:11; M 3.0 08:14 UT
Banda Sea M 3.9 08:04 UT
Crete M 3.5 07:58 UT
8320 0017 0025 0028 C2.7 (April 25, 2026) 1.7E-03
8330 0117 0133 0153 C4.6 (April 25, 2026) 7.5E-03
8460 0703 0708 0712 C1.3 (April 25, 2026) 7.5E-04
Taiwan M 4.2 07:16 UT
8480 0740 0746 0749 C2.5 (April 25, 2026) 1.0E-03
Coast of No. California M 3.8 07:39 UT
8510 0756 0759 0803 M1.3 (April 25, 2026) 3.9E-03
Crete M 3.5 07:59 UT
Northern California M 3.3 08:00 UT
Banda Sea M 3.9 08:04 UT
Unimak Island M 5.4 08:05 UT
8540 0930 0932 0935 C2.1 (April 25, 2026) 6.9E-04
Ecuador M 3.9 09:37 UT
Siberia M 4.8 09:40 UT
8550 0947 0954 0956 C3.2 (April 25, 2026) 1.3E-03
Central Peru M 4.6 09:53 UT
8610 1225 1231 1234 C1.4 (April 25, 2026) 7.1E-04
Timor Sea M 4.0 12:25 UT
Kenai, Alaska M 3.7 12:36 UT
8630 1312 1320 1328 C3.8 (April 25, 2026) 2.9E-03
Mindanao M 4.1 13:19 UT
Kamchatka M 4.5 13:22 UT M 4.5 13:23 UT
Chiapas M 4.2 13:27 UT
8660 1422 1430 1432 M1.1 (April 25, 2026) 2.8E-03
Iceland M 3.2 14:34 UT
Azpres M 2.0 14:38 UT
8700 1553 1602 1608 C2.1 (April 25, 2026) 1.7E-03
8770 1924 1938 1953 C3.9 (April 25, 2026) 4.4E-03
Papua M 4.1 19:42 UT
Coast of Oregon 19:21 UT
8800 2124 2126 2129 C3.5 (April 25, 2026) 1.0E-03
Myanmar M 4.2 21:27 UT
8840 2340 2348 2355 C1.9 (April 25, 2026) 1.3E-03
Offshore Northern California M 2.7, 2.9 23:40 UT 23:42 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 27-28 minor storms April 26. Solar M-flare chance: 75% X-class: 35% proton storm: 25%
AP Indicies: global: 9, high: 6, mid-latitude: 7, time of max AP: 22:00 UT; Max AP: 3 Global Kp 3.33 2100-2400, April 25; Sunspot Number: 154; Radio Flux: 148
April 25, 2026
Notable earthquakes and events:
Two X2.5 solar flares occurred early on UT April 24, 2026. They were accompanied by
a strong C8.0 flare about 3 hours later. The first X2.5 peaked at or near 01:07 UT
on April 24. The second peaked near 08:13 UT on April 24. Effects of this flare
on global systems were amplified when an M1.3 flare occurred at the same time (08:00 UT) on April 25. Areas near local solar
noon with the first of these X-class flares are located near 161 East longitude
and include Kamchatka and the Rat Islands of Alaska in the north and Vanuatu,
Santa Cruz and the Loyalty Islands to Kermadec Islands in the south. These are the most likely
longitude zones to see substantial seismic enhancement following this flare.
The flare near 08:00 UT on April 25 was accompanied by an M 3.3 in northern California within about a minute
of local solar midnight and an M 5.4 in the Unimak Island area of Alaska near local
solar midnight in that area several minutes after the M 3.2 in northern California.
These events area likely to have been triggered by SFE with this flare. Areas at local solar
noon with the second X-class flare are near 60E and those at midnight are near 120 W and include
active areas of California, Nevada and the western U.S. and Iran, Pakistan and
Afghanistan in the east. Moderate to strong earthquakes could occur in these
areas in the hours following these flares. Residents may take notice. These are the strongest solar flare cataloged by SWPC since an
X2.7 on May 14, 2025 (SWPC# 3410) nearly a year ago. CME from the two X-class
flares today have been observed and could hit the earth environment in several
days - about April 26-28. They could also help trigger geomagnetic storms which
may promote seismicity when they commence. A strong geomagnetic variation occurred on GOES magnetometers
beginning about 23:40 UT on April 24 and lasting through 01:20 UT on April 25.
An arcjet adjustment was required to adjust orbit on the GOES-19 satellite
beginning at about 23:47 on April 24. Seismicity at longitudes near the
International Date Line (180 degrees E/W) are most likely to be affected
by this geomagnetic excursion. A geomagnetic storm commenced with drastic reductions
in Electron Flux at GOES Satellite atltitudes and lasted through this writing
at about 09:00 UT. A slight elevation in proton count was also observed at this
time.
A moderate earthquake of M 5.4 accompanied the M1.3 solar flare on April 25, 2026.
It was followed by a series of light to moderate aftershocks of M 3.0-5.0.
NEIC reported the mainshock was felt with intensity up to IV in the epicentral
area. Intensity IV was recorded in Alaska at Akutan; III in Unalaska and II in False Pass.
The last earthquake in the Unimak Island area of Alaska with M>=5.4 was
catalogued as an M 5.7 on August 13, 2020. At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 5.6 in the Unimak Island area of Alaska. This epicenter
continues a westward migration of major aftershocks from the mainshock of M 7.8 on July 22, 2020 in the Alaska Peninsula.
Further strong seismicity in this migration is likely. The only event of M>=4.5
in the Unimak Island area in the past year was an M 4.7 on May 9, 2020. The only
events of equal or larger magnitude in the Unimak area of Alaska in the past
10 years occurred with M 5.7-5.8 on November 6, 2011 and October 27, 2016." (August 13, 2020)
This activity in the Unimak Island area occurred near the peak output of an M1.3
Solar flare and was probably promoted by energy associated with this flare.
Preliminary data for this flare from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
Unimak Is, Alaska M 5.4 08:05 UT
the Geysers, California M 3.3 08:00 UT
This epicenter is at the tenth node (36 degrees) from Honshu, Japan and at
the fifth node (72 degrees) from Tonga and Vanuatu and may have been promoted
by constructive energy interference from those sources.
O: 25APR2026 08:05:56 53.6N 164.9W MB=5.4 NEIC UNIMAK ISLAND AREA, ALASKA
O: 24APR2026 14:21:46 53.5N 164.8W ML=3.1 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:14:29 53.5N 164.8W ML=3.0 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:26:39 53.5N 164.8W ML=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:30:33 53.5N 164.9W ML=3.3 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:42:13 53.5N 164.8W ML=3.2 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:43:44 53.5N 164.7W ML=3.9 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:05:56 53.6N 164.9W Mw=5.4 EMSC UNIMAK ISLAND REGION, ALASKA
O: 25APR2026 08:11:09 53.6N 164.8W ML=3.5 EMSC UNIMAK ISLAND REGION, ALASKA
Several earthquakes also occurred with moderate magnitudes (M 4.5) in the
Rat Islands, Aleutians today. NEIC erported these were likely felt with
light intensity at Attu Station, Alaska. They may have been promoted by
the strong geomagnetic excursion on the UT morning of April 25 which
occurred when the Rat Islands were at local solar noon and/or by effects
from the X2.5 flare near 01:00 UT (near local solar noon) on April 24.
A more direct SFE effect from that flare can be seen in the discussion
in this summary of moderately large earthquakes in Kamchatka within
minutes of local solar noon.
O: 25APR2026 05:18:45 52.2N 176.6E MB=4.5 NEIC RAT ISLAND AREA, ALASKA
O: 25APR2026 05:18:45 52.2N 176.6E ML=4.5 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 25APR2026 04:16:06 51.8N 176.2E ML=4.4 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 25APR2026 05:18:45 52.2N 176.6E MB=4.5 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
O: 25APR2026 04:16:05 52.0N 176.3E MB=4.2 NEIC RAT ISLAND AREA, ALASKA
Several moderately strong earthquakes also occurred in Kamchatka, Russia today.
The strongest of these was an M 5.4 which was felt with moderate intensity
at Petropavlovsk-Kamchatsky with NEIC intensity up to IV. Kamchatka experienced
a number of major earthquakes in late 2025 but has been relatively quiet
during the first several months of 2026 to date. The last earthquake of M>=5.4
in Kamchatka was recorded as an M 5.9 on March 8, 2026. But the last such event within
about 200 km of today's epicenters was an M 5.5 on January 10, 2026. A stronog
M 6.0 hit the area on November 3, 2025. At the time this summary noted:
"The onset of the major geomagnetic storm coincided with an M 6.1 at high
latitudes in Kamchatka at 08:45 UT. This was followed by the most active
day in seismicity in Kamchatka since an M 7.8 on September 18, 2025 with
additional events of M 5.8 and 6.0 among others. The GOES magnetometer indicates
two spikes in field strength with the sudden commencement storm occurring
around 07:31-08:45 UT and 11:30-12:50 UT with a peak in electron flux also
at these times.
A strong solar flare of M5.0 today was the strongest recorded by SWPC since
an M6.4 on September 28, 2025 (flare 4370 M6.4). The last X-class flare
recorded was an X1.9 on June 19, 2025 (#2550). Data from SWPC for today's
M5.0 and a smaller M1.6 which ran into the M5.0 solar flare follow:
Readers may note that this was coincident with the M 6.1 earthquake in
Kamchatka which occurred about three minutes after the onset of this flare
activity.
...
The M 6.1 had been discussed in the previous issue of this summary as:
"A strong geomagnetic storm began at high latitudes today at about 09:00 UT November 3, 2025.
It reached high latitude k-index of 7 quickly, the strongest K-index at high latitudes in the previous month. This sudden commencement
storm is likely to trigger strong seismicity at high latitudes (Alaska, Kamchatka, Iceland for example)
at or near its onset with seismicity quickly returning to background shortly
thereafter.
A series of moderate to strong earthquakes occurred today in Kamchatka, Russia beginning with
the strong geomagnetic storm noted above. These included an M 5.8 and M 6.1
and were felt in the area of Petropavlovsk-Kamchatsky and Yelizovo, Russia.
These are aftershocks of the major earthquakes in Kamchatka of M 8.8 on July 29, 2025 and M 7.8 on September 18, 2025.
No earthquake of M>6.1 have occurred in Kamchatka since the M 7.8 of
mid-September 2025. Earthquakes of M 6.0-6.1 have occurred on October 3 and October 9, 2025 -
also with major geomagnetic storms." (November 3, 4, 2025)
With this in mind, it should come as no surprise to readers that today's
epicenters in Kamchatka were within minutes of local solar noon when the X2.5
flare peaked at 01:07 UT today (see above). This activity was likely
triggered by strong SFE with that flare.
Today's activity in Kamchatka is at the sixth node (60 degrees) from the Molucca Sea and
Malaysia and at the fifth node (72 degrees) from Tonga and may have been
promoted by energy from those sources.
O: 24APR2026 10:04:37 52.9N 160.9E MB=5.4 NEIC KAMCHATKA, RUSSIA
O: 24APR2026 10:04:32 52.8N 160.9E MW=5.4 EMSC OFF EAST COAST OF KAMCHATKA
O: 24APR2026 12:49:35 52.8N 161.0E Mw=5.1 EMSC OFF EAST COAST OF KAMCHATKA
O: 24APR2026 08:59:27 52.8N 161.0E MW=5.3 EMSC OFF EAST COAST OF KAMCHATKA
O: 24APR2026 08:59:28 52.9N 161.1E MB=5.3 NEIC KAMCHATKA, RUSSIA
An M 3.3 in the Geysers area of northern California also occurred today
within a minute or two of local solar midnight at the peak of the M1.3 solar
flare (see above). NEIC reported it was felt with intensity IV in California at Middletown; III in Healdsburg and II in Rohnert Park, Santa Rosa and Sebastopol.
It is highly likely it was triggered by SFE associated with that flare.
The last earthquake in the Geysers of California region with M>=3.3 occurred
as an M 3.3 a month ago on March 17, 2026 but the last of significantly
larger magnitude was an M 4.2 on February 21, 2026. At the time this summary noted:
"A moderate earthquake of M 4.2 occurred today in the area of the California Geysers north of San Francisco, California. NEIC reported intensity V in California at Middletown; IV in Lakeport and Kelseyville; III in Clearlake, Lower Lake, Hidden Valley, Guerneville, and II in Calistoga, Santa Rosa, Geyserville, Healdsburg, Napan, Novata and as far to the south as San Francisco.
NEIC reported an aftershock of M 2.9 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Kelseyville.
This epicenter in northern California is at 85 degrees from the Solomon Islands
and occurred 40 minutes and 40 seconds after it. This is the time it takes from
the surface wave to travel this distance from the Solomon Islands to northren
California. It is likely that the surface wave from the Solomon Islands
triggered the subsequent M 4.2 in northern California. This indicates
strong stress conditions in California at this time." (February 21, 2026)
O: 25APR2026 08:00:13 38.8N 122.7W MB=3.3 NEIC THE GEYSERS, NORTHERN CALIFORNIA
O: 25APR2026 08:00:13 38.8N 122.7W ML=3.3 EMSC NORTHERN CALIFORNIA
O: 24APR2026 13:45:28 38.8N 122.8W MD=2.6 EMSC NORTHERN CALIFORNIA
O: 25APR2026 01:14:48 38.8N 122.8W MD=2.1 EMSC NORTHERN CALIFORNIA
NEIC reported two earthquakes of M 4.0 off the coast of northern California was felt with intensity up to II-III in the area(s) of northern California in Garberville, Whitethorn, Petrolia, Ferndale, Fortuna and Eureka.
These earthquakes occurred near local solar midnight and local solar noon and may have been promoted
by the X2.5 solar flare of April 24 (see above).
O: 25APR2026 07:38:28 40.3N 124.9W MB=4.0 NEIC OFFSHORE COAST OF NORTHERN CALIFORNIA
O: 25APR2026 07:38:28 40.4N 124.9W MW=3.8 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 24APR2026 19:29:56 40.4N 125.1W MW=3.8 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 24APR2026 19:29:56 40.4N 125.1W MB=4.0 NEIC OFFSHORE COAST OF NORTHERN CALIFORNIA
A moderate earthquake of M 4.7-5.1 in the Fox Islands, Aleutians coincided with the peak output
of this flare at 01:01 UT. The last earthquake in the Fox Islands, Alaska
with M>=5.2 within about 200 km of today's epicenter occurred on March 5, 2026 with M 5.5.
Both of these area probably regional aftershocks of an M 6.1 on February 23, 2026.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 6.1 in the Fox Islands,
Aleutians, Alaska. It was followed by an M 5.5 aftershock.
NEIC reported these events were likely felt near Nikolski, Alaska with intensity up to IV.
The M 4.4 occurred near local solar midninght and may have been promoted by tidal and geomagnetic effects.
These earthquakes occurred near the fifth node (72 degrees) from the M 7.1 in
Malaysia and may have been promoted by FFA from that source." (February 23, 2026)
Today's event in the Fox Islands is at the 10th node (36 degrees) from Honshu, Japan and near the
fifth node (72 degrees) from Molucca, Vanuatu and Malaysia and was probably also promoted
promoted by energy from those sources.
The earthquake in the Fox Islands, Alaska occurred near local solar noon
and was likely promoted by solar flare effects with the major X2.5 flare.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
8000 0051 0107 0150 X2.5 (April 24, 2026) *
Fox Islands M 5.1 01:01 UT
Kermadec Is. M 5.4 01:52 UT
Crete M 5.9 03:19 UT
8050 0356 0401 0420 C8.0 (April 24, 2026) *
Chiapas M 4.0 03:55 UT
8070 0522 0530 0543 C3.1 (April 24, 2026) *
8100 0801 0813 0900 X2.5 (April 24, 2026) *
Banda Sea M 4.3 08:30 UT
Kuril Is. M 4.5 08:46 UT
Molucca M 4.6 08:41 UT
8120 0857 0907 0919 M1.9 (April 24, 2026) *
Crete M 5.3 08:58 UT
Kamchatka M 5.3 08:59 UT
The earthquake in Crete, Greece of M 5.8 was widely felt with felt aftershocks.
EMSC reported strong shake in Crete at Ferma, Koutsouras, Ferma, Koutsounari, Analipsi, Ierapetra, Kavousi, Gra Liyia, Sitia, Agios Nikolaos, Nea Anatoli, Xirokambos, Arvi, Elounda, Palekastro, Sision, Mokhos, Malia, Khersonisos, Limin Khersonisou, Gouves, Kato Gouves and as far as Gazi, Greece Alanya and Tavsanli, Turkey more than 600 km from the epicenter.
NEIC reported intensity VI in Crete, Greece at Kritsa, IV in Jentrion, Kato Khorion, Limin Khersonisou, Ierapetra, Palaikastron, III in Koutsouras, Aghios Nikolaos, Iraklion and Gournai.
A moderate aftershock of M 5.0 occurred near local solar noon in Crete on
April 24. EMSC reported it was felt lightly in Crete at Ferma, Sitia, Kavousi, Pacheia Ammos, Nea Alikarnassos, Irakleion, Agioi Theodoroi, Gazi. This followed at the end of the second X2.5 flare and at the beginning
of an M1.9 solar flare and was accompanied by a M 5.3 earthquake a minute later
in Kamchatka. These events were likely promoted by SFE from this flare.
Preliminary data on this and the second X2.5 flare today from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
8100 0801 0813 0900 X2.5 (April 24, 2026) *
Banda Sea M 4.3 08:30 UT
Kuril Is. M 4.5 08:46 UT
Molucca M 4.6 08:41 UT
8120 0857 0907 0919 M1.9 (April 24, 2026) *
Crete M 5.3 08:58 UT
Kamchatka M 5.3 08:59 UT
The last earthquake in the area of Crete, Greece of equal or larger magnitude
within about 200 km of today's epicenter occurred on May 22, 2025 following an M 6.0
on May 13-15, 2025 and may be an aftershock of
those mainshocks. It is of note that that earthquake occurred at the same
time as the last X-class flare of higher energy class to today's X2.5 occurred and was
noted as such in this summary at the time as:
"An earthquake of M 6.2 occurred today in Crete, Greece. A tsunami warning was issued after this earthquake, but only small fluctuations of sea level were expected.
The tsunami warning was later dropped. This eathquake was most widely felt in Chania dnd Rethymno, Crete.
Internet News reports indicated there was some dagate to buildings in Heraklion as well as landslides on
local roads. NEIC reported maximum intensity VII (slight damage) in Crete, Greece at Mokhos, Iraklion with V in Greece at Peristerion, Anissaras, Ayia Eirini, Dagnes, Gazion, Iraklion, Kato Gouvai, Nea Alikarnassos, Kerterados, Neapolis and in Tel Aviv, Israel, Emali, Antalya and Mugla, Turkey and in Egypt at Alexandria, El Daba and al-Qalyubiyah. Intensity IV was felt as far as 150 km at Rethimnon with III in Cyprus, Russia, Turkey, Saudi Arabia, Egypt, Greece, Israel, Lebanon, Libya, with lesser shaking as far as 1000 km from the epicenter.
EMSC reported strong shaking in Crete, Greece at Elounda, Mavrikiano, Schisma Elounta, Sision, Neapoli, Sisi, Siteia, Vrachasi, Agios Nikolaos, among many others.
Many of the larger aftershocks were also reported felt in Crete and Greece.
The last earthquake of M>=6.2 in Crete within about 200 km of this epicenter
occurred as an M 6.4 on October 12, 2021. At the time this summary noted:
"The strongest geomagnetic storm in more than three years occurred today. Bright, mostly
green aurora were seen throughout most of North America and Asia with this storm.
The height of the storm occurred between 09:00 and 10:00 UT. At the same time
an M 6.5 occurred in the sub-solar region of Crete, Greece and the Dodecanese
Islands. This summary had noted this geomagnetic storm as:
"The geomagnetic field saw major storm conditions today. The AP level was 45. High latitude geomagnetic field saw stormy conditions with AP 60. This is the strongest geomagnetic storm since AP reached 45 on September 1, 2019. The last of greater disturbance occurred occurred on August 26, 2018 when AP reached 76 and high latitude AP reached 90. Enhanced seismicity is likely at higher latitudes and near the geomagnetic equator with this storm in the next several days." (October 12, 2021)
A strong aftershock of M 6.4 also hit eastern Crete, Greece today. This event was
reported with maximum intensity VII in Crete at Sitia; IV in Ierapetra, Iraklion, and II-III in Nea Alikarnassos and Khanion, Greece.
Many buildings were damaged including a chapel which collapsed. People fled
from their homes during the quake but there were no immediate reports of casualties.
After a lull in the geomagnetic storm, it resumed about 07:00 UT on October 12, 2021
with high latitude AP 7 at about 09:00. It is likely that this helped
promote the earthquake in Crete at this same time. A strong M 6.0 hit Crete
about 200 km west of today's epicenter occurred on September 27, 2021, an earthquake which killed one and did considerable damage, and this may
be a regional aftershock of that event. The last earthquake of larger magnitude
in Crete occurred on May 2, 2020 with M 6.6, the strongest in the region
in the past 30 years. A similar M 6.6 about 200 km northeast of this occurred
on July 20, 2017. The only event of M>=6.4 within about 100 km of today's
event in the past 30 years was an M 6.4 on July 1, 2009. Today's earthquake
in Crete occurred within about an hour of local solar noon and was probably
promoted by high tidal stresses which maximize near this hour." (October 12, 2021)
A slightly smaller earthquake hit about 150 km from today's epicenter east of Crete on May 13, 2025 with M 6.0.
At the time this summary noted:
"This flare was followed by a major X2.5 flare which occurred about 08:00 UT on
May 14, 2025. It was followed by a series of moderate quakes and may promote
seismicity in (among other areas) the west coast of the U.S. ( at 120 West longitude - near local solar midnight at the time of the flare)
and in central Asia (60 East longitude) - local solar noon. This flare is the strongest
since a X9.0 on October 3, 2024 (SWPC #5530). Today's flares are likely to
trigger a geomagnetic storm in the next two days (and a bright aurora and
electronic malfunctions).
An earthquake of M 6.2 in Crete, Greece followed the X1.2 flare. This quake was felt widely in the region of Crete." (May 13, 2025, May 22, 2025)
This epicenter is near the fourth node (90 degrees) from the M 7.7 in Honshu,
Japan of April 20 and may have been promoted by energy from that source.
O: 24APR2026 03:18:53 35.0N 25.9E MW=5.8 NEIC CRETE, GREECE
O: 24APR2026 03:18:53 35.0N 25.9E MW=5.8 EMSC CRETE, GREECE
O: 24APR2026 09:26:45 35.0N 25.9E MB=4.7 EMSC CRETE, GREECE
O: 24APR2026 08:58:16 34.9N 26.1E Mw=5.0 EMSC CRETE, GREECE
O: 24APR2026 12:29:24 34.9N 26.1E mb=4.1 EMSC CRETE, GREECE
O: 24APR2026 14:10:22 34.9N 25.8E ML=4.0 EMSC CRETE, GREECE
O: 24APR2026 06:14:32 34.9N 26.1E ML=4.0 EMSC CRETE, GREECE
O: 24APR2026 08:58:17 35.0N 26.1E ML=5.0 NEIC CRETE, GREECE
O: 24APR2026 05:28:06 34.9N 26.1E ML=4.1 EMSC CRETE, GREECE
EMSC reported unusual earthquake of M 3.5 as occurring today in the region of Mississippi, USA.
This was not confirmed by NEIC so it is a questionable earthquake report.
O: 25APR2026 04:01:06 34.0N 89.6W ML=3.6 EMSC MISSISSIPPI
This reading follows a rare earthquake north of this epicenter in the New Madrid, Missouri
area which occurred on April 23 and was reported in this summary as:
O: 25APR2026 04:01:06 34.0N 89.6W ML=3.6 EMSC MISSISSIPPI
"The most unusual earthquake of the day was an M 4.0 in Southeastern Missouri.
NEIC reported it was felt with intensity IV in Arkansas at Turrell, Brookland, Marmaduke, in Missouri at Qulin, Steele, Caruthersville, Hornersville, and in Tennessee at Ridgely, Dover and Brighton and III as far as Illinois, Mississippi, Kentucky, Indiana, Texas,and in Ontario, Canada.
This is the first earthquake in Missouri within about 200 km of this epicenter
since an M 4.0 on November 18, 2021 and an M 4.0 on April 2, 2015. There have
been no earthquakes of greater magnitude in this area in the past 20 years.
At the time of the November, 2021 event this summary noted:
"The largest earthquake felt in the U.S. or Canada today was an M 4.0 in southeastern Missouri. NEIC reported it was felt with maximum intensity V in Missouri at Poplar Bluff, Fairdealing, and Fisk, Holcomg, Clarkton, Neelyville, Oxly with IV in Williamsville, Ellsinore, Grandin, Wappapello, and II-III in Mill Spring, Greenville, and Broseley. It was also felt lightly throughout most of the southern United States as far as New Mexico and Florida with moderate shaking in Mississippi, Arkansas, Kentucky, Tennessee, Indiana, Illinois.
This is the strongest earthquake in Missouri within about 100 km of this epicenter
since an M 4.2 more than 27 years ago on February 5, 1994. The only other event
of M>=4 in the region in the past 30 years of similar magnitude was an M 3.9-4.0
on April 2, 2015 about 150 km southeast of today's epicenter." (November 18, 2021)
This earthquake occurred at exactly local solar noon at a distance of 90.0
degrees from the M 7.7 in Honshu, Japan of April 20. It occurred at the tail
end of solar flare
It is highly likely that this earthquake in Missouri was triggered by
SFE from this flare.
This epicenter is at 90.0 degrees (node 4) from the M 7.7 in Honshu Japan
of April and had been expected as a far-field aftershock in that summary.
Other areas which are at the fourth node from Honshu include Crete, Greece (see
M 5.8 above), Ethiopia, New Zealand among others." (April 23, 2026)
NEIC reported an earthquake of M 4.1 in Taiwan was felt with intensity up to II-III in the area(s) of Taiwan at Sanchung, Taipei.
O: 25APR2026 07:16:34 24.8N 121.8W ML=4.1 NEIC TAIWAN
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 24, 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 when a flare occurred 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 0756 0759 0820 M1.3 (April 25, 2026) 3.9E-03 *
Unimak Is. Alaska M 5.4 08:05 UT M 3.5 08:11; M 3.0 08:14 UT
Banda Sea M 3.9 08:04 UT
Crete M 3.5 07:58 UT
8000 0051 0107 0150 X2.4 (April 24, 2026) 1.0E-01 *
Fox Islands M 5.1 01:01 UT
Kermadec Is. M 5.4 01:52 UT
Crete M 5.9 03:19 UT
Kamchatka M 5.3, 5.4
8050 0357 0401 0420 C7.9 (April 24, 2026) 2.8E-03
Chiapas M 4.0 03:55 UT
8070 0522 0530 0543 C3.1 (April 24, 2026) 3.8E-03
Crete M 4.0 05:28 UT
8090 0707 0711 0718 C3.9 (April 24, 2026) 2.4E-03
Myanmar M 4.4 07:03 UT
Northern Peru M 3.7 07:04 UT
New Ireland M 4.8 07:26 UT
8100 0801 0813 0830 X2.5 (April 24, 2026) 1.0E-01
Banda Sea M 4.3 08:30 UT
8120 0857 0907 0930 M1.9 (April 24, 2026) 1.9E-02 *
Crete M 5.0 08:58 UT, M 4.7 09:26 UT
Kamchatka M 5.3 08:59 UT
New Mexico M 2.5 08:58 UT
8140 1050 1057 1101 C4.5 (April 24, 2026) 2.9E-03
Siberia M 4.1 11:01 UT
8160 1216 1221 1230 C3.9 (April 24, 2026) 3.9E-03 *
Crete M 4.1 12:29 UT
Kamchatka M 5.1 12:49 UT
8170 1234 1301 1314 M1.7 (April 24, 2026) 2.7E-02
Kamchatka M 5.1 12:49 UT
8200 1433 1438 1445 C3.5 (April 24, 2026) 2.4E-03
Honshu, Japan M 3.5 14:33 UT
8240 1555 1606 1614 C3.7 (April 24, 2026) 3.5E-03
Flores M 4.5 16:10 UT
8260 1640 1644 1648 C3.4 (April 24, 2026) 1.7E-03
Andreanof Is. M 3.5 16:48 UT
8270 1704 1715 1726 C7.0 (April 24, 2026) 7.5E-03
8290 1754 1815 1900 M6.4 (April 24, 2026) 8.3E-02
Kermadec Is M 4.9 18:22 UT
Crete M 3.6 17:54 UT
New Zealand M 3.4 18:23 UT
Arizona M 2.1 18:47 UT
Greenland Sea M 4.3 18:51 UT
Off northern California M 3.8 19:29 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 27 minor stoms April 25-26. Solar M-flare chance: 75% X-class: 35% proton storm: 25%
AP Indicies: global: 9, high: 6, mid-latitude: 8, time of max AP: 08:00 UT; Max AP: 2 Global Kp 3.33 2100-2400, April 24; Sunspot Number: 123; Radio Flux: 146
April 24, 2026
Notable earthquakes and events:
Two X2.5 solar flares occurred early on UT April 24, 2026. They were accompanied by
a strong C8.0 flare about 3 hours later. The first X2.5 peaked at or near 01:00 UT
on April 24. The second peaked near 08:13 UT on April 24. Areas at local solar
noon with this flare are near 60E and those at midnight are near 120 W and include
active areas of California, Nevada and the western U.S. and Iran, Pakistan and
Afghanistan in the east. Moderate to strong earthquakes could occur in these
areas in the next several hour. Residents may take notice. These are the strongest solar flare cataloged by SWPC since an
X2.7 on May 14, 2025 (SWPC# 3410) nearly a year ago. CME from the two X-class
flares today have been observed and could hit the earth environment in several
days - about April 26-28. They could also help trigger geomagnetic storms which
may promote seismicity when they commence. A moderate earthquake
of M 4.7-5.1 in the Fox Islands, Aleutians coincided with the peak output
of this flare at 01:01 UT. The last earthquake in the Fox Islands, Alaska
with M>=5.2 within about 200 km of today's epicenter occurred on March 5, 2026 with M 5.5.
Both of these area probably regional aftershocks of an M 6.1 on February 23, 2026.
At the time this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 6.1 in the Fox Islands,
Aleutians, Alaska. It was followed by an M 5.5 aftershock.
NEIC reported these events were likely felt near Nikolski, Alaska with intensity up to IV.
The M 4.4 occurred near local solar midninght and may have been promoted by tidal and geomagnetic effects.
These earthquakes occurred near the fifth node (72 degrees) from the M 7.1 in
Malaysia and may have been promoted by FFA from that source." (February 23, 2026)
Today's event in the Fox Islands is at the 10th node (36 degrees) from Honshu, Japan and near the
fifth node (72 degrees) from Molucca, Vanuatu and Malaysia and was probably also promoted
promoted by energy from those sources.
The earthquake in the Fox Islands, Alaska occurred near local solar noon
and was likely promoted by solar flare effects with the major X2.5 flare.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0051 0107 0150 X2.5 (April 24, 2026) *
Fox Islands M 5.1 01:01 UT
Kermadec Is. M 5.4 01:52 UT
Crete M 5.9 03:19 UT
XXXX 0356 0401 0420 C8.0 (April 24, 2026) *
Chiapas M 4.0 03:55 UT
XXXX 0522 0530 0543 C3.1 (April 24, 2026) *
XXXX 0801 0813 0900 X2.5 (April 24, 2026) *
Banda Sea M 4.3 08:30 UT
Kuril Is. M 4.5 08:46 UT
Molucca M 4.6 08:41 UT
XXXX 0857 0907 0919 M1.9 (April 24, 2026) *
Crete M 5.3 08:58 UT
Kamchatka M 5.3 08:59 UT
O: 24APR2026 01:01:06 52.3N 168.3W MW=4.7 EMSC FOX ISLANDS REGION, ALASKA
O: 24APR2026 01:01:03 52.3N 168.3W MW=5.1 NEIC FOX ISLANDS REGION, ALASKA
O: 24APR2026 01:01:06 52.3N 168.3W MB=4.7 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 24APR2026 02:45:26 52.3N 168.5W ML=4.0 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 24APR2026 01:01:03 52.4N 168.3W mb=5.1 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
Moderate sized earthquakes also occurred during the X2.5 flare in the Kermadec Islands (M 5.4)
and in Crete, Greece (M 5.8).
O: 24APR2026 01:52:00 34.7S 179.2W MW=5.4 EMSC SOUTH KERMADEC ISLANDS
O: 23APR2026 17:46:13 34.8S 179.1W MB=4.8 EMSC SOUTH OF KERMADEC ISLANDS
O: 24APR2026 01:52:00 34.8S 179.2W MW=5.4 EMSC SOUTH OF KERMADEC ISLANDS
The earthquake in Crete, Greece of M 5.8 was widely felt with felt aftershocks.
EMSC reported strong shake in Crete at Ferma, Koutsouras, Ferma, Koutsounari, Analipsi, Ierapetra, Kavousi, Gra Liyia, Sitia, Agios Nikolaos, Nea Anatoli, Xirokambos, Arvi, Elounda, Palekastro, Sision, Mokhos, Malia, Khersonisos, Limin Khersonisou, Gouves, Kato Gouves and as far as Gazi, Greece Alanya and Tavsanli, Turkey more than 600 km from the epicenter.
NEIC reported intensity VI in Crete, Greece at Kritsa, IV in Jentrion, Kato Khorion, Limin Khersonisou, Ierapetra, Palaikastron, III in Koutsouras, Aghios Nikolaos, Iraklion and Gournai.
A moderate aftershock of M 5.0 occurred near local solar noon in Crete on
April 24. This followed at the end of the second X2.5 flare and at the beginning
of an M1.9 solar flare and was accompanied by a M 5.3 earthquake at the same
time in Kamchatka. These events were likely promoted by SFE from this flare.
Preliminary data on this and the second X2.5 flare today from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0801 0813 0900 X2.5 (April 24, 2026) *
Banda Sea M 4.3 08:30 UT
Kuril Is. M 4.5 08:46 UT
Molucca M 4.6 08:41 UT
XXXX 0857 0907 0919 M1.9 (April 24, 2026) *
Crete M 5.3 08:58 UT
Kamchatka M 5.3 08:59 UT
The last earthquake in the area of Crete, Greece of equal or larger magnitude
within about 200 km of today's epicenter occurred on May 22, 2025 following an M 6.0
on May 13-15, 2025 and may be an aftershock of
those mainshocks. It is of note that that earthquake occurred at the same
time as the last X-class flare of higher energy class to today's X2.5 occurred and was
noted as such in this summary at the time as:
"An earthquake of M 6.2 occurred today in Crete, Greece. A tsunami warning was issued after this earthquake, but only small fluctuations of sea level were expected.
The tsunami warning was later dropped. This eathquake was most widely felt in Chania dnd Rethymno, Crete.
Internet News reports indicated there was some dagate to buildings in Heraklion as well as landslides on
local roads. NEIC reported maximum intensity VII (slight damage) in Crete, Greece at Mokhos, Iraklion with V in Greece at Peristerion, Anissaras, Ayia Eirini, Dagnes, Gazion, Iraklion, Kato Gouvai, Nea Alikarnassos, Kerterados, Neapolis and in Tel Aviv, Israel, Emali, Antalya and Mugla, Turkey and in Egypt at Alexandria, El Daba and al-Qalyubiyah. Intensity IV was felt as far as 150 km at Rethimnon with III in Cyprus, Russia, Turkey, Saudi Arabia, Egypt, Greece, Israel, Lebanon, Libya, with lesser shaking as far as 1000 km from the epicenter.
EMSC reported strong shaking in Crete, Greece at Elounda, Mavrikiano, Schisma Elounta, Sision, Neapoli, Sisi, Siteia, Vrachasi, Agios Nikolaos, among many others.
Many of the larger aftershocks were also reported felt in Crete and Greece.
The last earthquake of M>=6.2 in Crete within about 200 km of this epicenter
occurred as an M 6.4 on October 12, 2021. At the time this summary noted:
"The strongest geomagnetic storm in more than three years occurred today. Bright, mostly
green aurora were seen throughout most of North America and Asia with this storm.
The height of the storm occurred between 09:00 and 10:00 UT. At the same time
an M 6.5 occurred in the sub-solar region of Crete, Greece and the Dodecanese
Islands. This summary had noted this geomagnetic storm as:
"The geomagnetic field saw major storm conditions today. The AP level was 45. High latitude geomagnetic field saw stormy conditions with AP 60. This is the strongest geomagnetic storm since AP reached 45 on September 1, 2019. The last of greater disturbance occurred occurred on August 26, 2018 when AP reached 76 and high latitude AP reached 90. Enhanced seismicity is likely at higher latitudes and near the geomagnetic equator with this storm in the next several days." (October 12, 2021)
A strong aftershock of M 6.4 also hit eastern Crete, Greece today. This event was
reported with maximum intensity VII in Crete at Sitia; IV in Ierapetra, Iraklion, and II-III in Nea Alikarnassos and Khanion, Greece.
Many buildings were damaged including a chapel which collapsed. People fled
from their homes during the quake but there were no immediate reports of casualties.
After a lull in the geomagnetic storm, it resumed about 07:00 UT on October 12, 2021
with high latitude AP 7 at about 09:00. It is likely that this helped
promote the earthquake in Crete at this same time. A strong M 6.0 hit Crete
about 200 km west of today's epicenter occurred on September 27, 2021, an earthquake which killed one and did considerable damage, and this may
be a regional aftershock of that event. The last earthquake of larger magnitude
in Crete occurred on May 2, 2020 with M 6.6, the strongest in the region
in the past 30 years. A similar M 6.6 about 200 km northeast of this occurred
on July 20, 2017. The only event of M>=6.4 within about 100 km of today's
event in the past 30 years was an M 6.4 on July 1, 2009. Today's earthquake
in Crete occurred within about an hour of local solar noon and was probably
promoted by high tidal stresses which maximize near this hour." (October 12, 2021)
A slightly smaller earthquake hit about 150 km from today's epicenter east of Crete on May 13, 2025 with M 6.0.
At the time this summary noted:
"This flare was followed by a major X2.5 flare which occurred about 08:00 UT on
May 14, 2025. It was followed by a series of moderate quakes and may promote
seismicity in (among other areas) the west coast of the U.S. ( at 120 West longitude - near local solar midnight at the time of the flare)
and in central Asia (60 East longitude) - local solar noon. This flare is the strongest
since a X9.0 on October 3, 2024 (SWPC #5530). Today's flares are likely to
trigger a geomagnetic storm in the next two days (and a bright aurora and
electronic malfunctions).
An earthquake of M 6.2 in Crete, Greece followed the X1.2 flare. This quake was felt widely in the region of Crete." (May 13, 2025, May 22, 2025)
This epicenter is near the fourth node (90 degrees) from the M 7.7 in Honshu,
Japan of April 20 and may have been promoted by energy from that source.
O: 24APR2026 03:18:53 35.0N 25.9E MW=5.8 NEIC CRETE, GREECE
O: 24APR2026 03:18:53 35.0N 25.9E MW=5.8 EMSC CRETE, GREECE
O: 24APR2026 06:14:32 34.9N 26.1E ML=4.0 EMSC CRETE, GREECE
O: 24APR2026 05:28:06 34.9N 26.1E ML=4.1 EMSC CRETE, GREECE
The most unusual earthquake of the day was an M 4.0 in Southeastern Missouri.
NEIC reported it was felt with intensity IV in Arkansas at Turrell, Brookland, Marmaduke, in Missouri at Qulin, Steele, Caruthersville, Hornersville, and in Tennessee at Ridgely, Dover and Brighton and III as far as Illinois, Mississippi, Kentucky, Indiana, Texas,and in Ontario, Canada.
This is the first earthquake in Missouri within about 200 km of this epicenter
since an M 4.0 on November 18, 2021 and an M 4.0 on April 2, 2015. There have
been no earthquakes of greater magnitude in this area in the past 20 years.
At the time of the November, 2021 event this summary noted:
"The largest earthquake felt in the U.S. or Canada today was an M 4.0 in southeastern Missouri. NEIC reported it was felt with maximum intensity V in Missouri at Poplar Bluff, Fairdealing, and Fisk, Holcomg, Clarkton, Neelyville, Oxly with IV in Williamsville, Ellsinore, Grandin, Wappapello, and II-III in Mill Spring, Greenville, and Broseley. It was also felt lightly throughout most of the southern United States as far as New Mexico and Florida with moderate shaking in Mississippi, Arkansas, Kentucky, Tennessee, Indiana, Illinois.
This is the strongest earthquake in Missouri within about 100 km of this epicenter
since an M 4.2 more than 27 years ago on February 5, 1994. The only other event
of M>=4 in the region in the past 30 years of similar magnitude was an M 3.9-4.0
on April 2, 2015 about 150 km southeast of today's epicenter." (November 18, 2021)
This earthquake occurred at exactly local solar noon at a distance of 90.0
degrees from the M 7.7 in Honshu, Japan of April 20. It occurred at the tail
end of solar flare
It is highly likely that this earthquake in Missouri was triggered by
SFE from this flare.
This epicenter is at 90.0 degrees (node 4) from the M 7.7 in Honshu Japan
of April and had been expected as a far-field aftershock in that summary.
Other areas which are at the fourth node from Honshu include Crete, Greece (see
M 5.8 above), Ethiopia, New Zealand among others.
O: 23APR2026 17:59:03 36.1N 89.8W MW=4.0 EMSC SOUTHEASTERN MISSOURI
O: 23APR2026 17:59:03 36.1N 89.8W MW=4.0 EMSC SOUTHEASTERN MISSOURI
O: 23APR2026 19:30:43 36.0N 89.8W ML=2.1 EMSC SOUTHEASTERN MISSOURI
A series of three M-class solar flares occurred on UT April 23. These are
the first M-class flares since an M1.0 on April 9, 2026 (#5000). The last
solar flare of M4.0 or greater was an M7.5 on April 4 (#4220).
Preliminary data on these flares from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0424 0435 0448 M1.6 (April 23, 2026)
Oklahoma M 2.1 04:32 UT
XXXX 0450 0459 0508 M1.2 (April 23, 2026)
South Sandwich Is. M 5.0 05:30 UT
XXXX 0748 0757 0806 C4.5 (April 23, 2026)
XXXX 0806 0811 0819 C5.6 (April 23, 2026)
Oklahoma M 2.3 08:13 UT
XXXX 0840 0848 0853 M4.3 (April 23, 2026)
XXXX 0947 0953 0957 C2.3 (April 23, 2026)
Southern Mid-Atlantic Ridge M 5.2 10:07 UT
XXXX 1330 1400 1411 M1.7 (April 23, 2026)
El Salvador M 4.8 14:09 UT
Tokyo M 4.0 14:53 UT
XXXX 1542 1617 1646 C7.4 (April 23, 2026) 1.8E-02
San Francisco, CA, M 2.3 16:13 UT
A moderate earthquake of M 4.8 in El Salvador occurred near the peak of the M1.7 solar flare on April 23.
Neic reported it was felt in El Salvador at Antiguo Cuscatlan, La Libertad and III in Nueva San Salvador, San Salvador and in El Rosario La Paz.
Preliminary data from SWPC for this solar flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1330 1400 1411 M1.7 (April 23, 2026)
El Salvador M 4.8 14:09 UT
O: 23APR2026 14:09:26 13.2N 89.4W ML=4.8 NEIC EL SALVADOR
O: 23APR2026 12:55:40 12.8N 88.3W ML=4.0 EMSC OFFSHORE EL SALVADOR
O: 23APR2026 14:09:24 13.1N 89.5W mb=4.8 EMSC OFFSHORE EL SALVADOR
O: 23APR2026 10:23:00 13.5N 90.1W ML=4.2 EMSC OFFSHORE EL SALVADOR
A light earthquake also coincided with the peak of solar flare C7.4 today in
the area of San Francisco, California. It was felt lightly in the area of Alum Rock
according to data from NEIC. Following is preliminary data for this solar
flare.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1542 1617 1646 C7.4 (April 23, 2026) 1.8E-02
San Francisco, CA, M 2.3 16:13 UT
This epicenter is at the fifth node (72 degrees) from Honshu and may have been
promoted by energy from that source.
O: 23APR2026 16:13:06 37.4N 121.8W ML=2.3 NEIC SAN FRANCISCO, CALIFORNIA
An unusual earthquake of M 5.2 occurred today in the southern Mid-Atlantic Ridge.
It was not reported felt in this remote area. The last earthquake of M>=5.2
within about 150 km of this epicenter occurred on February 1, 1995 with M 5.5. The
only other such event in the area in the past 35 years was an M 5.8 on March 22, 1992.
This epicenter in the South Atlantic is nearly antipodal to the remnants of
Typhoon Sinlaku which is currently located at about 40N 162E and may have
been promoted by energy from that source. It is also near to the antipode
of the M 7.7 in Honshu, Japan of April 20.
This event occurred at the end of a C2.3 flare and may have been promoted by SFE from it. Data for this
flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0947 0953 0957 C2.3 (April 23, 2026)
Southern Mid-Atlantic Ridge M 5.2 10:07 UT
This epicenter is located at the fifth node from the South Geomagnetic Pole
and may have been promoted by energy from that source.
O: 23APR2026 10:07:48 42.3S 18.4W ML=5.2 NEIC SOUTHERN MID-ATLANTIC RIDGE
O: 23APR2026 10:07:49 42.3S 18.4W MB=5.2 EMSC SOUTHERN MID-ATLANTIC RIDGE
NEIC reported an earthquake of M 4.2 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Kodiak.
O: 23APR2026 07:12:55 57.3N 153.3W ML=4.2 NEIC KODIAK, ALASKA
O: 23APR2026 07:12:56 57.4N 153.4W MW=4.2 EMSC KODIAK ISLAND REGION, ALASKA
EMSC reported an earthquake of M 4.9 in Guam, Mariana Islands was felt with intensity up to II-III in the area(s) of Guam, Mariana Islands in Santa Rita Village.
NEIC reported it was felt with intensity III in Guam at Santa Rita, Tamuning, Barrigada, Yigo, Mangilao and II in Merizo and Dededo and in Tinian, Mariana Islands.
Super Typhoon Sinlaku passed over this epicenter last week and enhanced seismicity
was expected at this epicenter in previous summaries as for example:
"STY SINLAKU 2026-04-14 00:00 UT 14.6N 146.0E 130 kts northeast of Guam
Super Typhoon Sinlaku (04W) continued today in the region northeast of Guam as a very powerful Super Typhoon with winds up to 160 kts. It is expected to track to the northeast over the next several days reaching the northern Marianas around April 14-17, 2026 as a major typhoon with winds up to 90 kts. Damage in the area of the Marianas is likely. Enhanced seismicity in the area of Guam is likely in the next week including the potential for a strong earthquake late in that period. The antipode at 14S 34W is near the southern mid-Atlantic Ridge and could see minor seismic enhancement at this time." (April 14-15, 2026)
O: 23APR2026 23:22:30 14.0N 144.9E ML=4.9 EMSC ROTA REGION, N MARIANA ISLANDS
NEIC reported an earthquake of M 4.5 in SE Honshu, Japan was felt with intensity up to II-III in the area(s) of SE Honshu, Japan in Tokyo and Kawasaki.
This earthquake occurred within minutes of local solar midnight and may
have been promoted by tidal and/or geomagnetic effects.
O: 23APR2026 14:53:15 35.7N 140.2E ML=4.5 EMSC NEAR EAST COAST OF HONSHU, JAPAN
EMSC reported an earthquake of M 3.4 in Strait of Gibraltar was felt with intensity up to IV in the area(s) of Strait of Gibraltar with strong but short shaking in Spain at Padul, Nerja, Almunecar, Malaga, Rincon de la Victoria.
This epicenter was near local solar midnight when the X2.5 flare occurred
today and may have been promoted by SFE associated with that event (see above).
O: 24APR2026 04:06:47 36.9N 3.8W ML=3.4 EMSC STRAIT OF GIBRALTAR
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 23, 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 when a flare occurred 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 0051 0107 0150 X2.5 (April 24, 2026) *
Fox Islands M 5.1 01:01 UT
Kermadec Is. M 5.4 01:52 UT
Crete M 5.9 03:19 UT
XXXX 0356 0401 0420 C8.0 (April 24, 2026) *
Chiapas M 4.0 03:55 UT
XXXX 0522 0530 0543 C3.1 (April 24, 2026) *
XXXX 0801 0813 0830 X2.5 (April 24, 2026) *
Banda Sea M 4.3 08:30 UT
7770 0424 0435 0448 M1.6 (April 23, 2026) 1.3E-02
Oklahoma M 2.1 04:32 UT
7780 0450 0459 0508 M1.2 (April 23, 2026) 1.3E-02
South Sandwich Is. M 5.0 05:30 UT
7810 0748 0757 0806 C4.5 (April 23, 2026) 4.7E-03
7820 0806 0811 0819 C5.6 (April 23, 2026) 4.5E-03
Oklahoma M 2.3 08:13 UT
7830 0840 0848 0853 M4.3 (April 23, 2026) 2.0E-02
7850 0947 0953 0957 C2.3 (April 23, 2026) 1.5E-03
Southern Mid-Atlantic Ridge M 5.2
7910 1342 1400 1411 M1.7 (April 23, 2026) 1.7E-02
El Salvador M 4.8 14:09 UT
7930 1514 1527 1542 C1.4 (April 23, 2026) 2.5E-03
San Francisco, CA, M 2.3 16:13 UT
7950 1700 1708 1714 M4.9 (April 23, 2026) 2.7E-02
Missouri M 4.0 17:59 UT
7750 0102 0117 0129 C4.4 (April 23, 2026) 4.8E-03
7760 0216 0223 0230 C1.9 (April 23, 2026) 1.6E-03
7970 1959 2006 2010 C4.1 (April 23, 2026) 2.2E-03
7990 2304 2316 2323 C3.6 (April 23, 2026) 2.9E-03
Guam M 4.9 23:22 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 24 active April 25 minor stoms April 26. Solar M-flare chance: 55% X-class: 10% proton storm: 10%
AP Indicies: global: 7, high: 10, mid-latitude: 7, time of max AP: 08:00 UT; Max AP: 3 Global Kp 3.00 0300-0600, April 23; Sunspot Number: 71; Radio Flux: 128
April 23, 2026
Notable earthquakes and events:
A series of three M-class solar flares occurred on UT April 23. These are
the first M-class flares since an M1.0 on April 9, 2026 (#5000). The last
solar flare of M4.0 or greater was an M7.5 on April 4 (#4220).
Preliminary data on these flares from SWPC follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0424 0435 0448 M1.6 (April 23, 2026)
Oklahoma M 2.1 04:32 UT
XXXX 0450 0459 0508 M1.2 (April 23, 2026)
South Sandwich Is. M 5.0 05:30 UT
XXXX 0748 0757 0806 C4.5 (April 23, 2026)
XXXX 0806 0811 0819 C5.6 (April 23, 2026)
Oklahoma M 2.3 08:13 UT
XXXX 0840 0848 0853 M4.3 (April 23, 2026)
XXXX 0947 0953 0957 C2.3 (April 23, 2026)
Southern Mid-Atlantic Ridge M 5.2 10:07 UT
XXXX 1330 1400 1411 M1.7 (April 23, 2026)
El Salvador M 4.8 14:09 UT
Tokyo M 4.0 14:53 UT
XXXX 1542 1617 1646 C7.4 (April 23, 2026) 1.8E-02
San Francisco, CA, M 2.3 16:13 UT
A moderate earthquake of M 4.8 in El Salvador occurred near the peak of the M1.7 solar flare on April 23.
Neic reported it was felt in El Salvador at Antiguo Cuscatlan, La Libertad and III in Nueva San Salvador, San Salvador and in El Rosario La Paz.
Preliminary data from SWPC for this solar flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1330 1400 1411 M1.7 (April 23, 2026)
El Salvador M 4.8 14:09 UT
O: 23APR2026 14:09:26 13.2N 89.4W ML=4.8 NEIC EL SALVADOR
A light earthquake also coincided with the peak of solar flare C7.4 today in
the area of San Francisco, California. It was felt lightly in the area of Alum Rock
according to data from NEIC. Following is preliminary data for this solar
flare.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1542 1617 1646 C7.4 (April 23, 2026) 1.8E-02
San Francisco, CA, M 2.3 16:13 UT
This epicenter is at the fifth node (72 degrees) from Honshu and may have been
promoted by energy from that source.
O: 23APR2026 16:13:06 37.4N 121.8W ML=2.3 NEIC SAN FRANCISCO, CALIFORNIA
An unusual earthquake of M 5.2 occurred today in the southern Mid-Atlantic Ridge.
It was not reported felt in this remote area. The last earthquake of M>=5.2
within about 150 km of this epicenter occurred on February 1, 1995 with M 5.5. The
only other such event in the area in the past 35 years was an M 5.8 on March 22, 1992.
This epicenter in the South Atlantic is nearly antipodal to the remnants of
Typhoon Sinlaku which is currently located at about 40N 162E and may have
been promoted by energy from that source. It is also near to the antipode
of the M 7.7 in Honshu, Japan of April 20.
This event occurred at the end of a C2.3 flare and may have been promoted by SFE from it. Data for this
flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0947 0953 0957 C2.3 (April 23, 2026)
Southern Mid-Atlantic Ridge M 5.2 10:07 UT
This epicenter is located at the fifth node from the South Geomagnetic Pole
and may have been promoted by energy from that source.
O: 23APR2026 10:07:48 42.3S 18.4W ML=5.2 NEIC SOUTHERN MID-ATLANTIC RIDGE
A series of three moderate earthquakes occurred on the afternoon of April 22 in the State of Nevada, USA.
These included an M 3.8 foreshock (felt in Dayton Nevada with intensity II) to an M 4.9 and an M 4.0 in a location about 250
km southeast of these half a minute later. They were followed by an M 4.6 in the area of Taiwan.
The larger event of M 4.9 in Nevada was reported by NEIC to have been felt with intensity V in Nevada at
Silver Springs; IV ion Virginia City and III in Carson City, Dayton, Gardnerville, Fallon, Washoe Valley and Sparks. EMSC reported it was felt
with intensity in Carson City, Nevada whereas the M 4.0 to the southeast
was reported by EMSC to have been felt as a strong event in Nevada at Fallon Station, Fallon, Johnson Lane, Carson City,
and Sparks. These felt reports, however appear to be related to the M 4.9
and are attributed to the third event by error.
Associated earthquakes in time also occurred at this time in Taiwan (M 4.6) and
in Central California (M 2.5) and may be related through SFE.
This set of earthquakes in Nevada appears to have been triggered by Solar Flare
Effects (SFE) with a C3.7 solar flare which maximized several minutes before
this series began near local solar noon. This is one of the three strongest
solar flares in the past week. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7650 1701 1714 1724 C3.7 (April 22, 2026) 3.4E-03
Nevada M 4.9 17:23 UT, M 4.0 17:24 UT, M 3.5 17:22 UT
Taiwan M 4.3 17:26 UT
The epicenters of the M 4.9 and the succeeding M 4.0 are at the fifth node (72 degrees) from the M 7.7
earthquake off northern Honshu, Japan of April 20 and may have been promoted
by energy from that source. The event to the southeast occurred 36 seconds after the M 4.9 mainshock.
The P-wave takes 31 seconds to traverse this distance. So it may have actually
triggered the M 4.0 event (or this is a AI error attributing a seismic
wave arrival to a local event).
O: 22APR2026 17:23:36 39.2N 119.1W ML=4.9 EMSC NEVADA
O: 22APR2026 17:22:13 39.2N 119.1W ML=3.8 EMSC NEVADA
O: 22APR2026 17:24:12 37.9N 117.3W ML=4.0 EMSC NEVADA
O: 22APR2026 17:22:13 39.3N 119.1W ML=3.5 EMSC NEVADA
O: 22APR2026 19:55:26 39.3N 119.1W ML=3.1 EMSC NEVADA
O: 22APR2026 17:23:37 39.3N 119.1W Mw=4.9 EMSC NEVADA
O: 22APR2026 17:26:13 24.0N 121.7E ML=4.6 EMSC TAIWAN
O: 22APR2026 17:40:22 36.9N 120.3W ML=2.5 EMSC CENTRAL CALIFORNIA
NEIC reported an earthquake of M 4.2 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Kodiak.
O: 23APR2026 07:12:55 57.3N 153.3W ML=4.2 NEIC KODIAK, ALASKA
O: 23APR2026 07:12:56 57.4N 153.4W MW=4.2 EMSC KODIAK ISLAND REGION, ALASKA
NEIC reported an earthquake of M 4.9 in the Northern Mid-Atlantic Ridge was was not felt in this remote area.
The last earthquake with M>=4.9 within about 200 km of this epicenter in the Northern Mid-Atlatnic Ridge
was an M 5.2 on December 2, 2025. TC Maila dissipated near the antipode of this earthquake last week and
may have influenced the position and timing of today's earthquake.
O: 22APR2026 08:35:51 10.4N 41.8W ML=4.9 NEIC NORTHERN MID-ATLANTIC RIDGE
O: 22APR2026 08:35:51 10.5N 41.9W MB=4.9 EMSC NORTHERN MID-ATLANTIC RIDGE
EMSC reported an earthquake of M 3.7 in Lebanon-Syria region was felt with intensity up to IV in the area(s) of Lebanon-Syria region in Lebanon at Aaey, Baabda, Aaley, Jdaidet el Matn, Bhamdoun el Mhatta, Beirut, Beit ed Dine, Jounieh, Joubb Jannine, Zahle, among others. It was accompanied by a loud earthquake noise.
This epicenter is at the fourth node (90 degrees) from the Molucca Sea and may have been promoted by energy from that source.
O: 23APR2026 00:10:50 33.8N 35.6E ML=3.7 EMSC LEBANON-SYRIA REGION
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 21, 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 when a flare occurred 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 1701 1715 1724 C3.7 (April 22, 2026) 3.3E-03
XXXX 0424 0435 0448 M1.6 (April 23, 2026)
Oklahoma M 2.1 04:32 UT
XXXX 0450 0459 0508 M1.2 (April 23, 2026)
South Sandwich Is. M 5.0 05:30 UT
XXXX 0748 0757 0806 C4.5 (April 23, 2026)
XXXX 0806 0811 0819 C5.6 (April 23, 2026)
Oklahoma M 2.3 08:13 UT
XXXX 0840 0848 0853 M4.3 (April 23, 2026)
XXXX 0947 0953 0957 C2.3 (April 23, 2026)
Southern Mid-Atlantic Ridge M 5.2
XXXX 1330 1400 1411 M1.7 (April 23, 2026)
El Salvador M 4.8 14:09 UT
XXXX 1542 1617 1646 C7.4 (April 23, 2026) 1.8E-02
San Francisco, CA, M 2.3 16:13 UT
7350 0132 0139 0144 C1.7 (April 22, 2026) 8.2E-04
Pakistan M 3.9 01:47 UT
7430 0422 0433 0440 C1.4 (April 22, 2026) 1.3E-03
Guerrero M 4.0 04:28 UT
7460 0610 0617 0620 C1.1 (April 22, 2026) 6.8E-04
7470 0623 0626 0628 C1.2 (April 22, 2026) 5.0E-04
Guerrero M 4.1 06:31 UT
Madagascar M 2.0 06:40 UT
Western Texas M 2.5 06:40 UT
7530 0950 0958 1009 C1.0 (April 22, 2026) 1.0E-03
Honshu M 4.2 09:49 UT
Oaxaca M 4.2 09:49 UT
7640 1635 1638 1641 C1.5 (April 22, 2026) 5.2E-04
Guerrero M 4.1 16:43 UT
7650 1701 1714 1724 C3.7 (April 22, 2026) 3.4E-03
Nevada M 4.9 17:23 UT, M 4.0 17:24 UT, M 3.5 17:22 UT
Taiwan M 4.3 17:26 UT
7700 1906 1920 1939 C2.3 (April 22, 2026) 3.3E-03
7730 2302 2314 2327 C3.0 (April 22, 2026) 3.2E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 23-25. Solar M-flare chance: 10% X-class: 1% proton storm: 1%
AP Indicies: global: 5, high: 5, mid-latitude: 4, time of max AP: 15:00 UT; Max AP: 2 Global Kp 1.67 2000-2400, April 22; Sunspot Number: 72; Radio Flux: 116
April 22, 2026
Notable earthquakes and events:
A series of three moderate earthquakes occurred on the morning of April 22 in the State of Nevada, USA.
These included an M 3.8 foreshock (felt in Dayton Nevada with intensity II) to an M 4.9 and an M 4.0 in a location about 250
km southeast of these half a minute later. They were followed by an M 4.6 in the area of Taiwan.
The larger event of M 4.9 in Nevada was reported by NEIC to have been felt with intensity V in Nevada at
Silver Springs; IV in Virginia City and III in Carson City, Dayton, Gardnerville, Fallon, Washoe Valley and Sparks. EMSC reported it was felt
with intensity in Carson City, Nevada whereas the M 4.0 to the southeast
was reported by EMSC to have been felt as a strong event in Nevada at Fallon Station, Fallon, Johnson Lane, Carson City,
and Sparks. These felt reports, however appear to be related to the M 4.9
and are attributed to the third event by error.
Associated earthquakes in time also occurred at this time in Taiwan (M 4.6) and
in Central California (M 2.5) and may be related through SFE.
This set of earthquakes in Nevada appears to have been triggered by Solar Flare
Effects (SFE) with a C3.7 solar flare which maximized several minutes before
this series began near local solar noon. This is one of the three strongest
solar flares in the past week. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 1701 1715 1724 C3.7 (April 22, 2026) 3.3E-03
The epicenters of the M 4.9 and the succeeding M 4.0 are at the fifth node (72 degrees) from the M 7.7
earthquake off northern Honshu, Japan of April 20 and may have been promoted
by energy from that source. The event to the southeast occurred 36 seconds after the M 4.9 mainshock.
The P-wave takes 31 seconds to traverse this distance. So it may have actually
triggered the M 4.0 event (or this is a AI error attributing a seismic
wave arrival to a local event).
O: 22APR2026 17:23:36 39.2N 119.1W ML=4.9 EMSC NEVADA
O: 22APR2026 17:22:13 39.2N 119.1W ML=3.8 EMSC NEVADA
O: 22APR2026 17:24:12 37.9N 117.3W ML=4.0 EMSC NEVADA
O: 22APR2026 17:26:13 24.0N 121.7E ML=4.6 EMSC TAIWAN
O: 22APR2026 17:40:22 36.9N 120.3W ML=2.5 EMSC CENTRAL CALIFORNIA
Aftershocks also continued following the M 7.4 (NEIC) to M 7.7 (JMA) earthquake
of April 20, 2026 off northeastern Honshu, Japan.
NEIC reported the largest aftershocks of M 5.3 and M 5.6 off northern Honshu, Japan was felt with intensity up to II-III in the area(s) of northern Honshu, Japan in Misawa, Aomori.
Data on tsunamis associated with this earthquake has now been made available
through JMA. An 80-cm tsunami was recorded at Kuji Port in Iwate Prefecture and smaller
tsunamis were registered in Hokkaido and along the northeastern coast of Honshu, Japan. At least 182,000 people evacuated due to the tsunami threat and a four-hour
suspension of bullet trains occurred. Injuries included elderly prople in Hokkaido and Iwate
Prefectures broke arms and legs while falling in the earthquake shaking.
O: 22APR2026 00:01:12 39.9N 143.2E ML=5.3 NEIC OFF NE HONSHU, JAPAN
O: 21APR2026 18:44:12 40.2N 143.5E ML=5.6 NEIC OFF NE HONSHU, JAPAN
O: 22APR2026 00:01:09 40.0N 143.1E MW=5.3 EMSC OFF EAST COAST OF HONSHU,
O: 22APR2026 09:49:07 40.0N 143.1E mb=4.2 EMSC OFF EAST COAST OF HONSHU,
O: 21APR2026 16:18:10 40.1N 142.2E ML=4.1 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 21APR2026 18:43:01 40.2N 143.2E mb=4.4 EMSC OFF EAST COAST OF HONSHU,
O: 21APR2026 18:44:11 40.2N 143.1E Mw=5.6 EMSC OFF EAST COAST OF HONSHU,
NEIC reported an earthquake of M 5.0 in Oaxaca, Mexico was felt with intensity up to II-III in the area(s) of Oaxaca, Mexico with III in Huatulco.
EMSC reported moderate shaking in Colonia Libertad, Mexico.
This epicenter is at 102 degrees from Honshu, Japan where an M 7.4 occurred
the day before and was probably promoted by energy from that source. Seismic
energy is reflected and refracted off the core-mantle boundary and returns
to the surface near this distance from the mainshock. Seismic activity
often appears enhanced at this distance following major earthquakes. Another
such example of this type of far-field triggering occurred in the Balleny
Islands today (see above).
O: 21APR2026 14:52:17 16.7N 95.8W MW=5.0 NEIC OAXACA, MEXICO
O: 21APR2026 14:52:21 16.9N 95.6W MB=5.0 EMSC OAXACA, MEXICO
O: 20APR2026 07:59:05 17.5N 94.8W ML=4.0 EMSC VERACRUZ, MEXICO
O: 20APR2026 09:03:38 17.1N 94.7W ML=4.0 EMSC OAXACA, MEXICO
O: 22APR2026 09:48:46 15.8N 95.0W ML=4.2 EMSC OFFSHORE OAXACA, MEXICO
O: 21APR2026 14:52:17 16.8N 95.7W MB=5.0 EMSC OAXACA, MEXICO
O: 21APR2026 21:11:16 16.8N 95.2W ML=4.2 EMSC OAXACA, MEXICO
NEIC reported an earthquake of M 5.7 in the Balleny Islands south of New Zealand was not felt in this remote area.
The last earthquake in the Balleny Islands within about 200 km of today's epicenter
occurred as an M 5.7 on January 7, 2024. The only event in the area in the
past 35 years of significantly larger magnitude in this area was an M 6.0 on January 31, 2016.
This summary noted in January 2024 some historical context for earthquakes
in the Balleny Islands area as:
"The strongest earthquakes in the world today were a pair of moderately large events
in the Balleny Islands south of New Zealand. These events of M 5.7 and M 5.4 occurred at 103 degrees from
The M 7.6 in western Honshu, Japan of January 1, 2024 and were probably promoted
by energy associated with that earthquake. An earthquake of equal or larger
magnitude than M 5.7 last occurred within about 250 km of this epicenter as an
M 5.8 on July 21, 2011. The only event of larger magnitude in the area in the
past 35 years was an M 6.9 on December 16, 1997. At the time of the M 5.8 in July, 2011
this summary noted:
"A series of moderate to strong earthquakes hit today at epicenters which
were the antipodes of active volcanism. The strongest of these was an M
5.6-6.0 in the Balleny Islands south of New Zealand. This is exactly
opposite on the earth to Iceland where volcanism has been active over the
past several weeks and months.
...
The earthquake in the Balleny Islands was the strongest in that region
in at least three years. A smaller M 5.5 hit the area on June 27, 2011.
The last earthquakes of similar or larger magnitude in the region occurred
on April 12, and April 16, 2007 with M 6.0 and 5.8.
The Balleny Islands are a remote sparsely populated region and today's
earthquake was not reported felt in the region. Followers of the P103 theory
may be interested to note that this epicenter is located at 103 degrees
from the mainshock in Japan of March 11. This suggest that some triggering
is possible at this distance from great earthquake because seismic energy
is concentrated at the surface at this distance." (July 21, 2011)
It is important to note that this summary written nearly 13 years ago is completely
congrueous with the current situation following a major quake in Japan at
103 degrees and a major eruption near the antipode in Iceland." (January 7, 2024)
Today's earthquake in the Balleny Islands is also at 103 degrees from
the M 7.4 in Honshu, Japan and was probably promoted by energy from that source.
It is also at the fourth node (90 degrees) from the remnants of Typhoon Sinlaku.
O: 21APR2026 10:30:27 62.0S 165.0E MW=5.7 NEIC BALLENY ISLANDS REGION
O: 21APR2026 10:30:25 62.4S 165.6E MW=5.7 EMSC BALLENY ISLANDS REGION
EMSC reported an earthquake of M 4.1 in Bali, Indonesia was felt with intensity up to II-III in the area(s) of Bali, Indonesia in Kangin, Uluwatu and Banjar Medura.
O: 21APR2026 20:59:49 9.5S 115.9E ML=4.1 EMSC SOUTH OF BALI, INDONESIA
O: 21APR2026 20:59:49 9.5S 115.9E ML=4.1 EMSC SOUTH OF BALI, INDONESIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
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 April 20, 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 when a flare occurred 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 1701 1715 1724 C3.7 (April 22, 2026) 3.3E-03
7090 0103 0115 0124 C1.3 (April 21, 2026) 1.3E-03
7120 0553 0602 0608 C5.3 (April 21, 2026) 2.3E-03
Slovenia M 3.6 05:58 UT
7130 0647 0655 0700 C1.4 (April 21, 2026) 1.2E-03
Ethiopia M 4.7 07:27 UT
7140 0942 0956 1006 C1.6 (April 21, 2026) 2.0E-03
Dominican Republic M 3.6 09:42 UT
Baja California M 3.0 09:45 UT
7160 1125 1130 1142 C2.2 (April 21, 2026) 1.8E-03
7170 1145 1150 1155 C4.0 (April 21, 2026) 2.0E-03
7190 1341 1402 1412 C1.4 (April 21, 2026) 2.2E-03
Northern California M 2.9 14:05 UT
7200 1415 1424 1440 C1.9 (April 21, 2026) 2.6E-03
Myanmar M 4.5 14:25 UT
Nevada M 2.6 14:26 UT
Northern California M 2.0 14:37 UT
7230 1629 1643 1656 C1.4 (April 21, 2026) 1.9E-03
7240 1825 1836 1849 C1.7 (April 21, 2026) 2.2E-03
Honshu M 5.6 18:44 UT, M 4.4 18:43 UT
Sumatra M 2.9 18:29 UT
Gibraltar M w.8 18:40 UT
7280 2120 2125 2137 C1.9 (April 21, 2026) 1.5E-03
7330 2313 2320 2325 C1.1 (April 21, 2026) 7.4E-04
Kuril Is. M 4.4 23:30 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 22-24. Solar M-flare chance: 10% X-class: 1% proton storm: 1%
AP Indicies: global: 19, high: 29, mid-latitude: 14, time of max AP: 15:00 UT; Max AP: 6 Global Kp 4.67 0000-0300, April 21; Sunspot Number: 68; Radio Flux: 112
April 21, 2026
Notable earthquakes and events:
A major M 7.4 earthquake occurred today off the northeast coast of Honshu, Japan.
NEIC reported intensity VII in Miyako, Iwate; VI in Hachinohe, Aomori, and Hasama, Miyagi and V in Misawa Aomori with IV in Hokkaido at Hakodate, Kitahiroshima, Namie, Fukushima, Tagajo, Miyagi, Narita, Chiba and Shiogama, Miyagi, Japan.
EMSC reported strong shaking in Japan at Aomori, Sendai, Noda, Sanriku coast, Chiba, Kamagaya, Toda, Urayasu, Tokyo, Kawasaki, Yokohama.
JMA reported the quake was felt with intensity up to VI on the Japanese Scale (out of 7)
in the areas of Hasikami, Aomori Prefecture and V in Iwate and Miyagi Prefectures. Sanriku, Iwate Prefecture. A tsunami warning has been issued by JMA
Possible tsunami waves up to 3 meters may occur in the Japanese areas of Hokkaido,
Miyagi, Fukushima and Aomori. The earthquake occurred in an area of a number of
nuclear power plants including Fukushima Daiichi and Daini in the Tokyo area
and Onagawa in Miyagi and Higashidori in Aomori Prefecture. Residents of
Japan are warned to avoid coastal areas at this time due to possible strong
currents and tidal waves. The last strong earthquake near today's epicenter
occurred as an M 6.5 on March 26. 2026. At the time this summary noted:
The earthquake off Honshu, Japan today occurred as a moderately strong
geomagnetic storm was commencing. The GOES-19 magnetometer shows this storm
beginning at about 07:20 UT on April 20 but a geomagnetic variation may have
started several hours earlier. The GOES-19 satellite position
had to be corrected with an arcjet maneuver due to this storm at 07:34 UT.
At this writing this storm has reached High latitude K of 6. It is likely
that this geomagnetic storm commencement helped promote this earthquake at
this time. The second strongest aftershock (M 5.4) at the time of this writing also was closely
associated with a major geomagnetic field variation recorded on GOES-19 and GOES-18 magnetometers.
This involved a near doubling of field intensity starting near 50 nT around 04:40 UT
and reaching a maximum near 100 nT at 05:30 UT on both GOES Magnetometers.
The M 5.4 aftershock occurred precisely at the peak of this field change
and may have been promoted by it. This aftershock was reported felt with intensity
up to III in the region of Miyako, Japan.
The strongest aftershock to this writing was an M 5.6 less than an hour after
the mainshock. This event may have been promoted by a C1.0 solar flare
which began at the same time as the M 5.6 in Honshu - the strongest observed solar flare in the past four days. It is likely
SFE helped promote this aftershock. Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7000 0833 0845 0852 C1.0 (April 20, 2026) 9.0E-04
Honshu M 5.6 08:33 UT
Banda Sea M 4.4 08:35 UT
Another factor which probably helped push this event to rupture was the
effects of Typhoon Sinlaku, a strong storm currently located in the Pacific
south of Honshu. In the past issue of this summary it had been noted as:
"TYP SINLAKU 2026-04-19 00:00 UT 27.6N 151.4E 65 kts East of Bonin Islands
Typhoon Sinlaku (04W) continued today in the region east of the Bonin Islands, Japan as a Typhoon with winds up to 65 kts. It is expected to track to the northeast over the next several days. The antipode at 27S 29W is near the southern mid-Atlantic Ridge and could see minor seismic enhancement at this time." (April 19, 2026)
This epicenter is at 103.6 degrees (node 7) from the south geomagnetic pole
and would be greatly influenced by strong geomagnetic storms. It is also at the ninth node (40 degrees)
from the Molucca Sea and Malaysia and at the sixth node (60 degrees) from Vanuatu and
and may have been promoted by constructive energy interference from those sources.
On April 17, 2026 this summary had noted the possibility of major changes
in the seismic pattern with the new moon of that date as:
"SWPC expects major geomagnetic storms beginning on April 17 and 18. These could trigger significant
seismic activity at their commencement longitudes (local solar noon and midnight).
Watch for a major change in global seismicity pattern starting with these storms
and the new moon of April 17, 2026." (April 16-27, 2026)
The epicenter of this event in Japan is also consistent with tidal stress
promotion with the new moon of April 17 which maximized near this longitude
as noted in previous issues of this summary:
"The new moon arrived on April 17, 2026 at 11:52 UT. Longitudes which are at local solar noon area near 0 W/E (GMT) and those at local solar midnight at 180 W/E (IDL). These longitudes include western Europe and much of the Mid-Atlantic Ridge system as well as the Vanuatu/Tonga/Fiji/New Zealand arc and the central and western Aleutians. These are the most likely areas to see enhanced tidal triggering in the next week. A strong tidally promoted earthquake is considered possible in the time period April 16-20, 2026." (April 15-19, 2026)
Some readers may find interest that forecast 181255 of this summary
had expected today's mainshock within about 10 km with moderate magnitude
was likely around April 19, 2026 as:
P: 19APR2026 181255 40.0N 143.0E 3.5-5.4 AAAAA Hokkaido, Japan
O: 20APR2026 10:44:13 39.5N 143.3E mb=5.0 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 16:13:16 39.5N 143.5E mb=4.4 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 08:14:45 39.6N 143.7E mb=4.9 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 08:32:43 39.6N 143.2E mb=5.6 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 12:56:45 39.6N 143.4E mb=5.1 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 09:07:30 39.7N 143.4E ML=4.4 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 11:28:58 39.7N 143.1E mb=4.5 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 09:49:41 39.8N 143.3E mb=5.1 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 08:23:56 39.9N 142.8E mb=5.0 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 20APR2026 08:30:07 39.9N 143.1E mb=4.7 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 14:15:29 39.9N 143.2E mb=4.7 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 21APR2026 05:19:57 39.9N 143.7E Mw=4.7 EMSC OFF EAST COAST OF HONSHU,
O: 21APR2026 05:29:10 39.9N 143.4E Mw=5.4 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 07:52:58 40.0N 143.0E Mw=7.4 EMSC NEAR EAST COAST OF HONSHU, JAPAN
O: 20APR2026 08:08:54 40.0N 143.4E mb=5.2 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 21APR2026 02:35:47 40.0N 143.2E mb=4.8 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 08:03:08 40.3N 143.8E mb=5.3 EMSC OFF EAST COAST OF HONSHU, JAPAN
O: 20APR2026 10:37:32 39.5N 143.4E MB=4.4 EMSC OFF EAST COAST OF HONSHU, JAPA
The earthquake in Honshu, Japan was followed about 3 hours later by a significant
regional earthquake off the coast of Northern California of M 4.7. NEIC reported
it was felt with intensity II in San Francisco and San Jose, California. This
event coincided with the commencement of a moderate geomagnetic storm which
GOES-18 shows starting at about 10:00 UT when this epicenter was near local
solar midnight. The last earthquake off the northern coast of California with M>=4.7 occurred on February 5, 2026 with M 4.7 but the
last of larger magnitude was an M 5.3 on December 15, 2024 - an aftershock of an M 7.0 on December 5, 2024.
At the time of the February, 2026 event. Analysis of this event was
presented in the previous issue of this summary.
An aftershock of M 3.4 occurred on April 21 within minutes of local midnight.
It was reported felt with intensity II in Whitethorn, California.
O: 20APR2026 10:41:31 40.3N 124.9W ML=4.7 NEIC OFF NORTH COAST OF CALIFORNIA
O: 20APR2026 10:41:35 40.3N 124.9W MW=4.7 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 20APR2026 20:31:53 40.3N 125.3W MD=2.6 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 20APR2026 13:26:20 40.4N 124.9W ML=3.5 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 21APR2026 08:58:58 40.3N 124.9W ML=3.4 NEIC OFF NORTH COAST OF CALIFORNIA
A far-field aftershock from Honshu, Japan occurred early on April 21, 2026 in Timor, Indonesia.
EMSC and NEIC reported it was felt with intensity III in East Timor at Dili and II in Kupang Nusa Tenggara.
The last earthquake within about 200 km of this epicenter with M>=5.5 occurred
on October 26, 2025 with M 6.2 and was reported in this summary as:
"The strongest earthquake in the world today was an M 6.2-6.3 in the Timor region of Indonesia.
BMG reported it was felt in Kab. Kupang at Amfoang te, Semau, Kupang, Sulamu, Amarasi, Fatuleu, Takari, Nekamese, Amabi, Taebenu, with III in Kab. Timor, Belu, alor, Flores, Sikka, Lembata, Rote Ndao, Malaka, Kupang, Sikka, Ende, Ngada, and II in Nagekeo, Sabu Raijua and Kepulauan Selayar.
NEIC reported intensity IV in Timur at Kipang Nusa and II in Dili with II in Northern Territory, Australia at Coonawarra and Darwin.
It occurred near local solar midnight and may have been promoted by tidal and/or
geomagnetic stresses which maximize near this hour.
...
The last earthquake ini Timor, Indonesia within about 200 km of this epicenter
with M>=6.3 occurred as an M 6.3 on November 4, 2015. At the time this summary noted:
"A strong geomagnetic storm hit today with AP levels up to 32 in equatorial and
mid-latitude zones. This is the strongest geomagnetic storm since October 7 when
the AP level reached 77. Seismic activity about 10-15 degrees either side of the
geomagnetic equator will likely be affected by this storm. This normally occurs
as the storm hits and/or about 4-6 days following the end of the storm.
...
A strong earthquake of M 6.3-6.6 in East Timor, Indonesia was preceded by an M 5.7
foreshock. The foreshock was reported by NEIC to have been felt in Dili, East Timor. The M 6.3-6.6
mainshock was reported felt with intensity V in Metinaro, Dili and in Dili, Indonesia. EMSC
reported moderate shaking in Dili, Jera, Pante Macassar, Kota Garut, Indonesia.
BMG reported it was felt with intensity IV-V in Alor and Atambua, Timor, Indonesia.
This epicenter is about 15 degrees south of the local geomagnetic equator and
occurred at the height of the strongest geomagnetic storm in about a month. It
is likely that this storm promoted this storm Indonesian earthquake. The immediate
trigger for this event was probably a strong M2.0 solar flare. This flare (unnumbered at this time)
maximized around 0323 UT within about 10 minutes of this earthquake. The quake
itself at 8S 125E occurred within minutes of local solar noon, a maximum time
for solar flare effects. In fact the epicenter was within a few degrees of the
exact sub-solar point when the quake occurred. The subsolar point is the point
on the earth that is exactly beneath the sun. At this time and point in the year,
the sub-solar point is about 10S 130E but was at 10S 126E at the time of the
solar flare maximum. This is a remarkable coincidence and a clear indication
that this earthquake was triggered by this solar flare." (November 4, 2015, October 26, 2025)
Today's epicenter is at 51.5 degrees (node 7) from the epicenter in Honshu hours
earlier and was probably promoted by constructive interference of energy from that source and from
Typhoon Sinlaku at the same distance and had been expected as a far-field
aftershock from Japan as published in previous issues of this summary:
"Node 7 (51.4 degrees)
Japan to Eastern Alaska, Yukon Canada, Banda Sea, New Guinea" (April 20, 2026)
A foreshock of M 5.2 occurred on April 20 and was reported in the previous issue
of this summary as:
"EMSC reported an earthquake of M 5.2 in Timor, Indonesia was felt with intensity up to IV in the area(s) of Timor, Indonesia in Dili.
O: 20APR2026 05:19:36 8.0S 124.3E ML=5.2 EMSC TIMOR, INDONESIA
O: 20APR2026 05:19:35 8.0S 124.3E MB=5.2 EMSC KEPULAUAN ALOR, INDONESIA " (April 20, 2026)
O: 21APR2026 03:17:07 9.1S 124.1E ML=5.5 NEIC TIMOR, INDONESIA
O: 21APR2026 03:17:07 9.1S 124.1E MW=5.5 EMSC TIMOR REGION
O: 21APR2026 03:19:20 9.1S 124.2E ML=4.4 EMSC TIMOR REGION
NEIC reported an earthquake of M 5.7 in the Balleny Islands south of New Zealand was not felt in this remote area.
The last earthquake in the Balleny Islands within about 200 km of today's epicenter
occurred as an M 5.7 on January 7, 2024. The only event in the area in the
past 35 years of significantly larger magnitude in this area was an M 6.0 on January 31, 2016.
This summary noted in January 2024 some historical context for earthquakes
in the Balleny Islands area as:
"The strongest earthquakes in the world today were a pair of moderately large events
in the Balleny Islands south of New Zealand. These events of M 5.7 and M 5.4 occurred at 103 degrees from
The M 7.6 in western Honshu, Japan of January 1, 2024 and were probably promoted
by energy associated with that earthquake. An earthquake of equal or larger
magnitude than M 5.7 last occurred within about 250 km of this epicenter as an
M 5.8 on July 21, 2011. The only event of larger magnitude in the area in the
past 35 years was an M 6.9 on December 16, 1997. At the time of the M 5.8 in July, 2011
this summary noted:
"A series of moderate to strong earthquakes hit today at epicenters which
were the antipodes of active volcanism. The strongest of these was an M
5.6-6.0 in the Balleny Islands south of New Zealand. This is exactly
opposite on the earth to Iceland where volcanism has been active over the
past several weeks and months.
...
The earthquake in the Balleny Islands was the strongest in that region
in at least three years. A smaller M 5.5 hit the area on June 27, 2011.
The last earthquakes of similar or larger magnitude in the region occurred
on April 12, and April 16, 2007 with M 6.0 and 5.8.
The Balleny Islands are a remote sparsely populated region and today's
earthquake was not reported felt in the region. Followers of the P103 theory
may be interested to note that this epicenter is located at 103 degrees
from the mainshock in Japan of March 11. This suggest that some triggering
is possible at this distance from great earthquake because seismic energy
is concentrated at the surface at this distance." (July 21, 2011)
It is important to note that this summary written nearly 13 years ago is completely
congrueous with the current situation following a major quake in Japan at
103 degrees and a major eruption near the antipode in Iceland." (January 7, 2024)
Today's earthquake in the Balleny Islands is also at 103 degrees from
the M 7.4 in Honshu, Japan and was probably promoted by energy from that source.
It is also at the fourth node (90 degrees) from the remnants of Typhoon Sinlaku.
O: 21APR2026 10:30:27 62.0S 165.0E MW=5.7 NEIC BALLENY ISLANDS REGION
O: 21APR2026 10:30:25 62.4S 165.6E MW=5.7 EMSC BALLENY ISLANDS REGION
NEIC reported an earthquake of M 5.0 in Oaxaca, Mexico was felt with intensity up to II-III in the area(s) of Oaxaca, Mexico with III in Huatulco.
EMSC reported moderate shaking in Colonia Libertad, Mexico.
This epicenter is at 102 degrees from Honshu, Japan where an M 7.4 occurred
the day before and was probably promoted by energy from that source. Seismic
energy is reflected and refracted off the core-mantle boundary and returns
to the surface near this distance from the mainshock. Seismic activity
often appears enhanced at this distance following major earthquakes. Another
such example of this type of far-field triggering occurred in the Balleny
Islands today (see above).
O: 21APR2026 14:52:17 16.7N 95.8W MW=5.0 NEIC OAXACA, MEXICO
O: 21APR2026 14:52:21 16.9N 95.6W MB=5.0 EMSC OAXACA, MEXICO
O: 20APR2026 07:59:05 17.5N 94.8W ML=4.0 EMSC VERACRUZ, MEXICO
O: 20APR2026 09:03:38 17.1N 94.7W ML=4.0 EMSC OAXACA, MEXICO
NEIC reported an earthquake of M 5.2 in Ecuador was felt with intensity up to II-III in the area(s) of Ecuador with III in Quito, Pichincha, Saquisili, Cotopaxi, and II in Imbabura at Otavalo, Cotacachi and Ibarra.
EMSC reported moderate shaking in Ecuador at Tutamandahostel and Santo Domingo de los Colorados.
O: 21APR2026 02:22:21 00.3N 78.3W MW=5.2 NEIC ECUADOR
O: 21APR2026 02:22:20 0.4N 78.4W MW=5.2 EMSC COLOMBIA-ECUADOR BORDER REGION
NEIC reported an earthquake of M 5.0 in India was felt with intensity up to II-III in the area(s) of India with intensity IV in Manipur III in Assam and Nagaland at Nagaon, Kohima, Dimapur, Silchar, Dispur, and Shillong and in Bangladesh at Silhat and Dacca.
EMSC reported it was felt with moderate shaking in India at Imphal, Manipur, Heirangoithong, Kohima, Silchar, Karimganj, Jorhat, Khliehriat, Tezpur, Naharlagun, Shillong, Morigaon, Jagiroad, Nongpoh, Dispur, Guwahati, Barpeta Road and in Bangladesh at Tungi, Paltan, Dhaka, Azimpur, Jamalpur.
O: 21APR2026 00:29:35 24.6N 94.6E MW=5.0 NEIC INDIA
O: 21APR2026 00:29:33 24.7N 94.6E MB=5.0 EMSC MYANMAR-INDIA BORDER REGION
EMSC reported an earthquake of M 4.7 in Kamchatka was felt with intensity up to IV in the area(s) of Kamchatka at Petropavlovsk-Kamchatsky.
O: 20APR2026 07:27:07 51.1N 157.1E MB=3.9 EMSC NEAR EAST COAST OF KAMCHATKA
O: 21APR2026 01:55:25 52.8N 159.4E mb=4.7 EMSC OFF EAST COAST OF KAMCHATKA
O: 21APR2026 01:55:25 52.8N 159.4E MW=4.7 NEIC OFF THE EAST COAST OF KAMCHATKA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TYPHOON SINLAKU (04W)
---- ------- ---------- -------- ----- ------ ------- ---------------
TYP SINLAKU 2026-04-21 00:00 UT 29.8N 161.2E 45 kts East of Honshu, Japan
Typhoon Sinlaku (04W) continued today in the region east of Honshu, Japan as a Typhoon with winds up to 45 kts. It is expected to track to the northeast over the next several days. The antipode at 30S 19W is near the southern mid-Atlantic Ridge and could see minor seismic enhancement at this time,
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of April 20, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
7000 0833 0845 0852 C1.0 (April 20, 2026) 9.0E-04
Honshu M 5.6 08:33 UT
Banda Sea M 4.4 08:35 UT
South Island, NZ M 3.8 08:41 UT
7030 1458 1514 1525 C1.6 (April 20, 2026) 2.1E-03
Sumatra M 4.1 15:16 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet April 23 unsettled April 22 and active April 21. Solar M-flare chance: 5% X-class: 1% proton storm: 1%
AP Indicies: global: 24, high: 37, mid-latitude: 13, time of max AP: 08:00 UT; Max AP: 6 Global Kp 5.00 1800-2100, April 20; Sunspot Number: 46; Radio Flux: 105
April 20, 2026
Notable earthquakes and events:
A major M 7.4 earthquake occurred today off the northeast coast of Honshu, Japan.
NEIC reported intensity VII in Miyako, Iwate; VI in Hachinohe, Aomori, and Hasama, Miyagi and V in Misawa Aomori with IV in Hokkaido at Hakodate, Kitahiroshima, Namie, Fukushima, Tagajo, Miyagi, Narita, Chiba and Shiogama, Miyagi, Japan.
EMSC reported strong shaking in Japan at Aomori, Sendai, Noda, Sanriku coast, Chiba, Kamagaya, Toda, Urayasu, Tokyo, Kawasaki, Yokohama.
JMA reported the quake was felt with intensity up to VI on the Japanese Scale (out of 7)
in the areas of Hasikami, Aomori Prefecture and V in Iwate and Miyagi Prefectures. Sanriku, Iwate Prefecture. A tsunami warning has been issued by JMA
Possible tsunami waves up to 3 meters may occur in the Japanese areas of Hokkaido,
Miyagi, Fukushima and Aomori. The earthquake occurred in an area of a number of
nuclear power plants including Fukushima Daiichi and Daini in the Tokyo area
and Onagawa in Miyagi and Higashidori in Aomori Prefecture. Residents of
Japan are warned to avoid coastal areas at this time due to possible strong
currents and tidal waves. The last strong earthquake near today's epicenter
occurred as an M 6.5 on March 26. 2026. At the time this summary noted:
"A moderate geomagnetic storm occurred today at high latitudes. K-index for this
storm was 5 from about 1100 UT to 1600 UT on March 26, 2026. An M 6.5 earthquake
occurred at the maximum of this geomagnetic storm in the region off the coast
of northern Honshu, Japan when it was local solar midnight in Japan.
...
A strong earthquake occurred today off the coast of northern Honshu, Japan with M 6.5. NEIC
reported it was felt in the epicentral area of northern Honshu with intensity V in Morioka, Iwate; IV in Hakodate, Hokkairo and Misawa, Aomori and II in Sendai Miyagi and may have been felt as far as Shizuoka and Saitama Prefectures. EMSC reported moderate shaking in Sendai, Japan.
A minor tsunami could be associated with this event.
This earthquake is the strongest within about 200 km of this epicenter since an M 6.7 on December 12, 2025 about 200 km northwest of
this epicenter. The last within the 200 km radius of larger magnitude was an
M 6.7 on February 16, 2015. At the time this summary noted:
"A strong earthquake of M 6.3-6.7 in the South Sandwich Islands today was followed
65 minutes later by a similar M 6.7-6.9 near the coast of northern Honshu, Japan.
Seismic waves including reflected S-waves from the South Sandwich Islands were in
the area of the epicenter in Japan when that earthquake occurred. Geomagnetic
effects from the recent geomagnetic storm may also have had a triggering effect
on these events. Promotion of seismicity in these areas may also have occurred following
the recent strong earthquakes in the North Atlantic (M 7.1) and Vanuatu (M 6.8).
The distance relations between these event and today's large earthquakes is
interesting. The earthquake in the South Sandwich Islands is at 106-108 degrees
from the North Atlantic and also at 106-108 degrees from Vanuatu. This is in the
distance zone in which seismic energy refracted and reflected from the core-mantle
boundary concentrates. Seismicity often is enhanced in this distance zone following
strong earthquakes. The earthquake in Honshu, Japan was located at the sixth node
(60 degrees) from Vanuatu and the fourth node (90 degrees) from the North Atlantic.
Both are also at the third node (120 degrees) from the series of strong earthquakes
in Molucca at the end of 2014 and some triggering from that source is likely as well.
Strong earthquakes in or near Honshu, Japan, which is in the general antipodal area of
the South Sandwich Islands often follow shortly after strong earthquakes in
the South Sandwich Islands (SSI). The last earthquakes of M>=6.5 in the South Sandwich
Is. area occurred on June 29, 2014, followed by the last strong earthquake
in Honshu - an M 6.5 on July 11, 2014. The previous event in the SSI area of
M>=6.5 hit on March 6, 2011, five days before the grea M 9.1 Fukushima earthquake
and tsunami of March 11, 2011 and three days before the M 7.1 foreshock in Honshu. The next event prior to that an M 6.9-6.9 in the SSI
are occurred on September 6, 2004 and was preceded on September 5, 2004 of M 7.4 and followed
on September 6, 2004 by a Japanese event of M 6.6. The event prior to that
in the SSI area was an M 6.6 on July 25, 1994 preceded on July 21, 1994 by
an M 7.3 in the Sea of Japan. A coupled pair also occurred when an M 6.7 in the SSI
area on January 10, 1993 was followed by a strong M 7.6 in Hokkaido on January 15, 1993.
The relation is clear. In the past 21 years there have been six earthquakes
of M>=6.5 in the SSI area. Four of these have been associated within four days
with a similar earthquake in the Honshu area and five have been so associated
within two weeks. Only one SSI event of this magnitude in the past 21 years
was not associated with a similar event in Honshu - an M 6.5-6.8 on November 7, 2000.
The earthquake in Honshu, Japan may have been immediately triggered by the
strongest solar flare of the day - a high B- or C-class flare which, according to SWPC data
began about 2304 UT, the same time as the Honshu earthquake. NEIC reported this earthquake
was felt with intensity V in Kitakami and Yamada, IV in Morioka, Misawa and II-III in Kariyama, Chitose, Sapporo, Sendai, Tokyo, Sagamihara, Tsuchiura, Musashino, Naton, Maramachi, Narita, Matsudo, Yuzawa and Wakuya,
A moderate aftershock of M 4.7 further east was felt with intensity II in Misawa, Aomori, Japan.
JMA reported the mainshock was felt with intensity IV in Aomori, Iwate, Miyagi, Akita, III in Hokkaido, Yamagata, II in Fukushima, Niigata, Ibaraki, Tochigi, Gunma, Saitama, Chiba, Kanagawa, Yamanashi, and I in Tokyo, Nagano, and Shizuoka Prefectures, Japan.
JMA reported an aftershock of M 5.7 was felt with intensity 5+ in Aomori, V- in Iwate, III in Miyagi, Akita, II in Hokkaido, Yamagata, Fukushima, Ibaraki and I in Gunma, Saitama, and Niigata Prefectures, Japan.
An M 4.6 aftershock was felt with intensity I in Iwate. Other aftershocks were felt lightly in Iwate, Miyagi and Fukushima Prefectures.
Tsunami warnings were issued by JMA but after only small tsunamis were observed, the
warnings were withdrawn. A 10-20 cm tsunami was reported in Iwate Prefecture. There
was no reported damage at nuclear power plants. No major damages or casualties
were reported with these earthquakes. Residents were warned away from the ocean
in case of further seismic activity." (February 16, 2015)
Today's Honshu earthquake occurred within minutes of local solar midnight and was
probably promoted by tidal and/or geomagnetic stresses which maximize near
this hour. An aftershock of M 4.6 occurred within two minutes of local solar
midnight, the largest such aftershock at the time of this writing.
A moderate geomagnetic storm peaked about the same time as the earthquake
with K-index of 5 at high latitudes. It may have helped trigger the subsequent
earthquake in Honshu.
A foreshock of M 4.6 was reported in the preliminary issue of this summary as:
This earthquake was close associated with a strong geomagnetic excursion on the GOES-18 magnetometer
and may have led to the subsequent activity in the area of Honshu.
This epicenter is at 103 degrees from the South Geomagnetic Pole and was
probably promoted by the recent geomagnetic storms. It is also near the
fifth node (72 degrees) from Tonga; at sixth node (60 degrees) from the strong Tropical Cyclone Narelle and
may have been promoted by energy from that source. Other earthquakes near
the fifth node from Tonga occurred as an M 4.0 in the Ryukyu Islands, Japan; Central
California, the Central East Pacific Rise (M 4.9); the Kuril Islands (M 4.7);
the Andreanof and Fox Islands, and the Alaska Peninsula." March 26, 2026)
The nuclear facilities are being examined for damage at this writing. This is the same area that the M 9+ earthquakes
of March 11, 2011 occurred and is possible an aftershock of a similar earthquake
in the region on December 8, 2025 of M 7.6. At that time this summary noted:
"A major M 7.6 earthquake in northern Honshu and southern Hokkaido occurred
on December 8, 2025 with the following parameters (via EMSC):
A strong aftershock of M 6.6 folowed about 7.5 hours after the mainshock.
NEIC reported it was felt with intensity IV in Hachinohe, Aomori, Japan and II in Iwanai, Hokkaido.
...
A tsunami warning was issued by PTWC but observed sea-level fluctuations were less than
a meter and the tsunami warning was later withdrawn.
NEIC reported intensity VII in Aomori, Japan at Hachinohe and in Misawa and VI in Date, Hokkaido with V in Iwate, Aomori, Hokkaido, Miyagi Prefectures.
EMSC reported strong shaking in Hokkaido and northern Honshu, Japan including
reports of minor damage in Japan at Misawa, Takizawa, Morioka, Sapporo, Niseko Town, Otaru, Koriyama, Narita, Fukayacho, Soka, Kamagaya, Narashino, Wako, Urayasu, Tokyo and as far to the south as 700 from the epicenter and at Yuzhno-Kurilsk, and Otrada Russia.
The mainshock was followed by an M 5.5 aftershock 18.5 minutes later.
Following this earthquake, the Japanese Meteorological Agency (JMA) issued
a warning that this earthquake may preceded a mega-thrust earthquake of
M>=8. While the details of why JMA felt such a warning was necessary at this time
are not known, the great earthquakes in Kamchatka of July 29, 2025 (M 8.8)
and September 18, 2025 (M 7.8) may serve as a cautionary sign. It is also
possible JMA personnel are recalling the great quake of March 11, 2011
of M>9 in the same general region which triggered a massive tsunami and
killed tens of thousands while doing enormous damage to much of Japan.
The earthquake was preceded by a foreshock of M 7.2 on March 9, 2011. At the time
this summary reported:
"As noted at the time of the last moderate earthquakes in this region of Japan,
seismic activity in this region is often triggered by unusually strong solar
flares. On February 15 and X2.2 flare was followed by events of M 5.4 and 5.7
at the same epicenter as today's earthquake, events which were foreshocks
to those of today. At the time we noted:
"A pair of moderate earthquakes also occurred north of Indonesia in
the area off the east coast of Honshu, Japan today with M 5.4, 5.7.
These earthquake were well offshore and were not reported felt on
the Japanese mainland. This epicenter was also subsolar during the great
X2.2 flare today. Japan often shows strong triggering with major
flares on the sun. The timing places the earthquake occurring four minutes
after flare 7180, a C1.7 flare." (February 15, 2011)
As with the foreshocks of February 15, the mainshock today occurred about 15 minutes after local solar noon (sub-solar).
At exactly local solar noon the largest solar flare of the day, a C6.4 class solar flare
occurred which may have been the immediate trigger for this earthquake.
The largest flare since the X2.2 on February 15 occurred several hours
earlier on March 8 as an M3.7 flare (#1830)." (March 9, 2011)
The mainshock of magnitude about 9.3 occurred three days later on March 11, 2011
and was reported in this summary at the time as:
"The immediate trigger for this earthquake was probably a sudden change
in the geomagnetic field strength. SWPC reports that a major geomagnetic
storm began on March 10 about 20:00 UT and continued through the early
portions of March 11. At this time, this appears to be the strongest
geomagnetic storm in at least half a year although the precise numbers have not yet
been published. SWPC reports a sudden increase in the Hp and Total Field
strength beginning a few minutes before the Japan earthquake and peaking
within about a minute of that earthquake. GOES-15 shows this a bit more
gradually than GOES-13 which shows a strong spike at the minute the
earthquake occurred at 06:46 UT in the Hp field. This is possibly related to a strong
electron flux event at the same time and was accompanied by a strong
increase in the geomagnetic disturbance index KP to red alert status, a
status which has seldom been reached in recent years." (March 11, 2011)
and
"The next moderate aftershock in Japan occurred at 23:36 UT about five minutes
after an X1.5 class solar flare, the second in the past half year after
one on February 15.
Flare # START MAX END CLASS DATE
2540 2313 2323 2329 X1.5 (March 9, 2011) 6.7E-02" (March 10, 2011)
As a major geomagnetic storm is expected within hours and a further X-class
solar flare is likely, the JMA advisory is perhaps better understood at
this time.
The last earthquake within about 300 km of this epicenter in northern Japan
with M>=7.6 occurred on September 25, 2003 with M 8.1-8.3. At the time this
summary noted:
"A great earthquake (Me>=8.0) occurred in the region of eastern Hokkaido,
northern Japan today (Sept. 25 UT, morning Sept. 26, JST).
...
According to CNN and AP news sources, today's earthquake caused damage throughout Hokkaido, triggered
power blackouts, fires and train derailment. A tsunami was produced with
maximum wave height of 3 feet at Kushiro. That tsunami is expected in Hawaii
early this morning. No deaths are know to have occurred at this time. Damage
included cracked roads and considerable damage to built structures. This appears
to be the strongest event in the region of Hokkaido since the Tokachi-Oki
earthquake of May 16, 1968 which registered around M 8.0. That earthquake
caused severe damage at Tokachi-Oki, Aomori Perfecture, Japan including
up to $800 million at Niigata and killed up to 48 people. A strong tsunami
was associated with that earthquake as well. Today's earthquake
has been followed by an active aftershock sequence and several regional aftershocks.
Classical local aftershocks are those that occur within the rupture zone of
the mainshock and have occurred with M 7.0, 6.0, 6.1, 5.9, 5.3, 4.4, 4.1, 6.2 and
5.5. A far-field aftershock may have occurred at an intermediate depth with
M 5.2 in the Sakhalin, Russia area (data from the National Earthquake Information
Service - NEIS; the Geological Survey of Russia - GSR and the Broadband
Seismograph Network - NIED, Japan).
"The region of Hokkaido has seen several moderate earthquakes (M 4.0-5.5) over
the past several days. GSR reported an additional event with M 4.7 in the
region on September 23. geoForecaster does not expect associated damage with
this event. This appears to be the strongest event in the region 42-43N 143-146E
since an M 5.4 on July 8, an aftershock of an M 5.8 that occurred on July 2, 2003
and also appears to be the strongest aftershock of that event since early July." (September 25, 2003)
Today's earthquake 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:
"An X1.1 class solar flare occurred early on the UT December 8. It was accompanied
by moderate earthquakes in Myanmar (M 3.8); Yukon Territory, Canada (M 3.6) and the
Kuril Islands (M 4.5). No strong earthquakes were immediately associated with this flare.
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
If a major earthquake is to occur it would most likely rupture to the north
and east into the Kuril Islands. This is a region which has been relatively
quiet in recent years but where major earthquakes do occur.
Today's epicenter is at the seventh node from the M 7.0 in Yukon, Canada of
December 6, 2025 and at the eighth node (45 degrees) from the north Geomagnetic
Pole and 104 degrees from the South Geomagnetic pole and may have been
promoted by energy from those sources.
More details will follows as this situation develops, especially if more X-class
flares or a major geomagnetic storm occur later today.
Expected far-field seismicity enhancement after today's Hokkaido earthquake:
Antipodal (180 degrees)
Japan to South Atlantic
Outer shadow zone edge (142-150 degrees)
Japan to Northern Chile, Central/South Atlantic, West Chile Rise, South Shetland Islands
Node 3 (120 degrees)
Japan to Dominican Republic and Virgin Islands Venezuela, Galapagos, Antarctic-Pacific Ridge, Canary Is,
Inner shadow zone edge (101-108 degrees)
Japan to Chiapas, Oaxaca, Mexico, Azores,
Node 4 (90 degrees)
Japan to Central Mediterranean, Ethiopia, South Island, New Zealand, West Texas, Jalisco, Mexico
Node 9 (80 degrees)
Japan to Turkey, Baja California
Node 5 (72 degrees)
Japan to central, northern California, Iceland, Eastern Turkey, Iran, Caucasus, Fiji, Tonga,
Node 6 (60 degrees)
Japan to Vanuatu, Vancouver, Sumatra,
Node 7 (51.4 degrees)
Japan to Eastern Alaska, Yukon Canada, Banda Sea, New Guinea
Node 8 (45 degrees)
Japan to Indonesia, Myanmar, southern Alaska," (December 8, 2025)
JMA has indicated a slight chance of a following mega-quake in the Chisima Trough. Residents
are being advised to update their earthquake preparedness at this time. At this
writing no deaths or injuries have been reported with this earthquake.
The earthquake off Honshu, Japan today occurred as a moderately strong
geomagnetic storm was commencing. The GOES-19 magnetometer shows this storm
beginning at about 07:20 UT on April 20 but a geomagnetic variation may have
started several hours earlier. The GOES-19 satellite position
had to be corrected with an arcjet maneuver due to this storm at 07:34 UT.
At this writing this storm has reached High latitude K of 6. It is likely
that this geomagnetic storm commencement helped promote this earthquake at
this time.
Another factor which probably helped push this event to rupture was the
effects of Typhoon Sinlaku, a strong storm currently located in the Pacific
south of Honshu. In the past issue of this summary it had been noted as:
"TYP SINLAKU 2026-04-19 00:00 UT 27.6N 151.4E 65 kts East of Bonin Islands
Typhoon Sinlaku (04W) continued today in the region east of the Bonin Islands, Japan as a Typhoon with winds up to 65 kts. It is expected to track to the northeast over the next several days. The antipode at 27S 29W is near the southern mid-Atlantic Ridge and could see minor seismic enhancement at this time." (April 19, 2026)
This epicenter is at 103.6 degrees (node 7) from the south geomagnetic pole
and would be greatly influenced by strong geomagnetic storms. It is also at the ninth node (40 degrees)
from the Molucca Sea and Malaysia and at the sixth node (60 degrees) from Vanuatu and
and may have been promoted by constructive energy interference from those sources.
On April 17, 2026 this summary had noted the possibility of major changes
in the seismic pattern with the new moon of that date as:
"SWPC expects major geomagnetic storms beginning on April 17 and 18. These could trigger significant
seismic activity at their commencement longitudes (local solar noon and midnight).
Watch for a major change in global seismicity pattern starting with these storms
and the new moon of April 17, 2026." (April 16-27, 2026)
The epicenter of this event in Japan is also consistent with tidal stress
promotion with the new moon of April 17 which maximized near this longitude
as noted in previous issues of this summary:
"The new moon arrived on April 17, 2026 at 11:52 UT. Longitudes which are at local solar noon area near 0 W/E (GMT) and those at local solar midnight at 180 W/E (IDL). These longitudes include western Europe and much of the Mid-Atlantic Ridge system as well as the Vanuatu/Tonga/Fiji/New Zealand arc and the central and western Aleutians. These are the most likely areas to see enhanced tidal triggering in the next week. A strong tidally promoted earthquake is considered possible in the time period April 16-20, 2026." (April 15-19, 2026)
Some readers may find interest that forecast 181255 of this summary
had expected today's mainshock within about 10 km with moderate magnitude
was likely around April 19, 2026 as:
P: 19APR2026 181255 40.0N 143.0E 3.5-5.4 AAAAA Hokkaido, Japan
O: 20APR2026 07:52:58 40.0N 143.0E Mw=7.4 EMSC NEAR EAST COAST OF HONSHU,
O: 20APR2026 07:53:00 40.0N 143.0E ML=7.4 NEIC OFF NORTHEAST COAST OF HONSHU, JAPAN
O: 20APR2026 10:44:16 39.5N 143.2E MB=5.0 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 08:32:46 39.6N 143.3E mb=5.6 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 09:07:30 39.7N 143.4E ML=4.4 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 09:49:43 39.8N 143.3E mb=5.1 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 08:08:54 40.0N 143.4E mb=5.2 EMSC OFF EAST COAST OF HONSHU,
O: 20APR2026 08:03:08 40.3N 143.8E mb=5.3 EMSC OFF EAST COAST OF HONSHU,
The earthquake in Honshu, Japan was followed about 3 hours later by a significant
regional earthquake off the coast of Northern California of M 4.7. NEIC reported
it was felt with intensity II in San Francisco and San Jose, California. The last
earthquake off the northern coast of California with M>=4.7 occurred on February 5, 2026 with M 4.7 but the
last of larger magnitude was an M 5.3 on December 15, 2024 - an aftershock of an M 7.0 on December 5, 2024.
At the time of the February, 2026 event this summary noted:
"The strongest earthquake in the U.S. or Canada today was an M 4.7 off the coast of northern California.
NEIC reported it was widely felt in northern California with intensity IV in Rio Dell; III in Scotia, Trinidad, Loleta, Whitethorn, Fortuna, Bayside, San Francisco, Arcata, Eureka, Samoa, Laytonville, McKinleyville, and II in Ferndale, Garberville, Kneeland an Blue Lake, California.
The last earthquake off the coast of Northern California with M>=4.7 occurred
as an M 5.3 on December 16, 2024 - an aftershock of an M 7.0 on December 5, 2024.
At the time this summary noted:
"A major earthquake of M 7.0-7.3 occurred on December 5, 2024 near local noon off the coast of Northern California.
The Joint Typhoon Warning Center (JTWC) gave this event M 7.3 and several other magnitudes were
given by various international agencies, but it appears to qualify as a "major" earthquake.
...
It also occurred while a northeast clipper was hitting the northeastern U.S. Both of these are
possible triggers for such an event. The epicenter of this earthquake is about 104-105
degrees from a series of events including an M 5.7 in southern Iran yesterday
and may have been promoted by energy from that source.
A tsunami warning for the west coast of the U.S. was issued but tsunamis from
large earthquakes in this area are not usually powerful and it is likely
that any tsunami associated with today's event would be in the centimeters
height range. This warning was later withdrawn when no significant tsunami
waves were observed.
A series of moderate earthquake in the Geysers area of northern California
followed the M 7.0 off the California coast. They were likely triggered
by P- and/or S-waves from that earthquake. This series included events of M 2.5 and 4.3.
NEIC reported these were felt with intensity up to III in northern and Central
California at Felton, San Jose, Santa Rosa, Yuba City, Rohnert Park and Fremont.
Today's mainshock was reported by NEIC to have been felt with damage with intensity
VIII at Redcrest and VII in Ferndale and Rio Dell. Intensity VI was reported thoughout most
of Northern California including at Alderpint, Carlotta, Fortuna, Garberville, Hydesville, Loleta, Myers Flat, Scotia, Whitethorn and Six Rivers National Forest. Intensity V was felt as far as 150 km of the epicenter; IV up to 300 km as far as Oregon and III in Nevada and the remainder of California. Light shaking of II was reported in Arizona, Washington, Oregon, British Columbia, and within about 500 km of the epicenter.
Earthquakes in this area can occur in pairs and can help trigger far-field
seismicity, so readers are advised not to relax quite yet.
The last earthquake within about 200 km of today's epicenter off the coast of
Northern California with M>=7 occurred as an M 7.0-7.1 on June 15, 2005. Other
such event (all of M 7.0-7.1) in the past 35 years occurred on August 17, 1991, April 25, 1992,
and September 1, 1994. At the time of the last such earthquake off the coast
of northern California, this summary noted:
"Strong earthquakes occurred today in two areas of the U.S. and Canada. The
strongest of these was an M 7.0-7.5 which occurred late tonight off the coast
of Northern California. This was preceded by an earthquake of M6.6-6.8 in the
Rat/Andreanof Islands region of the central Aleutian Islands, Alaska. A
tsunami warning was issued by the USGS following the event off the coast
of Northern California. That earthquake was strongly felt along the coast
of Oregon and California and was reported slightly felt as far away as
Keller, Texas and Berthoud, Colorado. It was felt to the south as far as Los Angeles.
and as far to the north as Colville, Washington more than 1000 km away from
the epicenter. The quake was also felt in the Seattle area. Maximum felt
intensity was VI at Myrtle Point, Oregon. This is the first event located
in the region off the coast of California (38-42N 124-130W) since an earthquake
of M 7.1 on Sept. 1, 1994 (M 7.1) and April 25, 1992 (M 7.1). The largest
earthquake previously located in the region was an M 7.2 on Nov. 8, 1980
(NEIC data) If the current magnitude of M 7.4 is not revised downward, this
would be the strongest earthquake ever recorded in this region off the northern
coast of California (the largest previous had been M 7.3 on Jan. 31, 1922).
This summary had expected a strong earthquake in the region could occur
at this time. We had emphasized this in our lead article in this summary three
weeks ago on May 23, 2005 and to a lesser extent on Feb. 25, 2005 in this
summary. Readers may read these warning summaries in full by clicking on
more> below. The area was under very strong seismic watch conditions at
the time of the quake. This seismic watch arose from triggering effects
from the landfall of Tropical Storm Arlene, a strong geomagnetic storm two
days ago and the occurrence of a great earthquake in Chile yesterday (M 7.8-7.9)
in addition to a recent activation of the area." (June 15, 2005)
In the previous issues this summary had detailed the lull in major seismic
global activity preceding today's event (see summaries and updates for December 1-5 for
details). This earthquake at M 7.0 is a "major event"
earthquake" and occurs 102-103 days after the last earthquake of M 6.9 in Tonga
on August 26, 2024, not quite breaking the length of the previous quiet period
of 103-104 days in 2019.
When a slightly smaller event of M 6.9 hit the coast of Northern California
on March 10, 2014, this summary noted the strong quiet period preceding it as:
"A strong earthquake of M 6.9 hit off the coast of Northern California early
on March 10 (March 9 local time). NEIC reported this earthquake was widely
felt along the coast of northern California. Maximum intensity V was felt
at Blue Lake and Samoa with intensity IV at Eureka, Ferndale, MacKinleyville, North Bend, Whitethorn, Trinidad, Rio Dell, Loleta, Hydesville, Barberville, Fortuna, Ferndale, Bayside, Arcata, Littleriver, California. Intensity II-III was felt in Brisbane, Daly City, Billbrae, San Gregorio, San Francisco, Oakland, Albany, San Rafael, Bodega, Inverness, Mill Valley, Aptos, Boulder Creek, Santa Cruz, Scotts Valley, Santa Rosa, Albion, Compiche, Elk, Fort Bragg, Guerneville, Mendocino, Ukiah, Willits, Bridgeville, Burnt Ranch, Carlotta, Crescent City, Klamath, Korbel, Myers Flat, Salyer, Somes Bar, Zenia, Davis, Esparto, Lincoln,Dutch Flat, Sacramento, Chico, Grass Valley, Magalia, Nevada City, Paradise, Quincy, Chico, Redding, Big Bar, Dunsmuir, Gerber, Hayfork, Lewiston, Mount Shasta, Palo Cedro, Weaverville, Crescent City, Klamath, Point Arena and San Mateo. It was also felt in Oregon with intensity IV in North Bend and II-II in Klamath Falls, Selma, O'Brien, Grants Pass, Cave Junction, North Bend, Gold Beach, Brookings and Eugene.
A foreshock of M 3.3 occurred about 15 minutes before the mainshock but was
not reported felt in the area. A smaller foreshock occurred about noon today.
NEIC reported this earthquake of M 2.6 off the coast of Northern California was felt with intensity II-III in the area(s) of Rio Dell, California.
This is the strongest earthquake to hit off northern California since an M 7.2
on June 15, 2005 and an M 7.1 on September 1, 1994. A series of events in July and
August, 1991 and on April 25, 1992 registered M 6.9-7.1 in the area. It is also
the strongest earthquake in the United States outside Alaska since the Easter
Day earthquake in Baja California of April 4, 2010. The epicenter of that event,
however was not within the borders of the U.S. and the last event within the U.S.
territorial borders were the events of June 2005 and September 1994.
It is also the strongest earthquake in the world since an event of M 7.8 in
the Scotia Sea on November 17, 2013." (March 11, 2014, December 5, 2024)
Today earthquake also appears to have been triggered by a strong solar Flare. An M 1,7 class fkare bega
...
This epicenter is at 102 degrees from Mindanao; at the fifth node (72 degrees) from
Honshu, Japan, and at the third node (120 degrees) from the South Geomagnetic
Pole and may have been promoted by energy from those sources." (February 5, 2026)
Today's event off northern California was located at 103.6 degrees from the
Molucca Sea and at the fifth node (72 degrees) from Typhoon Sinlaku and
may have been promoted by energy from those sources.
O: 20APR2026 10:41:31 40.3N 125.0W MW=4.7 EMSC OFFSHORE NORTHERN CALIFORNIA
O: 20APR2026 10:41:31 40.3N 124.9W ML=4.7 NEIC OFF NORTH COAST OF CALIFORNIA
NEIC reported an earthquake of M 4.7 in the Rat Islands, Alaska was felt with intensity up to II-III in the area(s) of the Andreanof Islands, Alaska with III in Adak, Alaska.
This epicenter is located at the 13th node (27.5 degrees) from the earthquake
several hours earlier in Honshu, Japan and may have been promoted by energy from
that source. It may also have been affected by energy from the geomagnetic
storm in progress at the time as it lies at 36 degrees (node 10) from the Northern
Geomagnetic Pole and at the third node (120 degrees) from the South Geomagnetic pole.
It occurred near the IDL where enhanced seismicity was expected with the new
moon of April 17 (see above) and may have been promoted by tidal stresses.
O: 20APR2026 09:54:45 51.6N 179.3E ML=4.7 NEIC RAT ISLANDS, ALASKA
O: 20APR2026 09:54:45 51.1N 179.3E MB=4.7 EMSC RAT ISLANDS, ALEUTIAN ISLANDS
Another area near the IDL (180 E/W longitude) which has experienced strong
tidal stresses with the new moon has been the area of the Kermadec Islands.
This area remained active today with the largest event M 5.2 which may have
been felt in the epicentral area. This earthquake occurred within a couple
of minutes of local solar noon, a time when tidal stresses maximize.
O: 19APR2026 23:52:30 32.3S 178.0W ML=5.2 NEIC KERMADEC ISLANDS
O: 20APR2026 00:19:20 32.6S 177.4W ML=4.9 NEIC KERMADEC ISLANDS
O: 19APR2026 19:55:37 32.4S 177.9W ML=4.9 NEIC KERMADEC ISLANDS
O: 19APR2026 19:01:11 32.5S 178.1W ML=4.7 NEIC KERMADEC ISLANDS
O: 19APR2026 17:17:59 32.4S 177.9W MB=4.3 EMSC SOUTH OF KERMADEC ISLANDS
O: 19APR2026 19:01:11 32.5S 178.1W mb=4.7 EMSC SOUTH OF KERMADEC ISLANDS
O: 19APR2026 23:52:31 32.5S 177.7W mb=5.2 EMSC SOUTH OF KERMADEC ISLANDS
O: 19APR2026 19:55:40 32.6S 177.9W mb=4.9 EMSC SOUTH OF KERMADEC ISLANDS
O: 20APR2026 00:19:20 32.6S 177.1W mb=4.9 EMSC SOUTH OF KERMADEC ISLANDS
O: 20APR2026 07:04:15 32.6S 177.0W mb=5.1 EMSC SOUTH OF KERMADEC ISLANDS
O: 19APR2026 19:54:04 32.7S 177.0W mb=4.5 EMSC SOUTH OF KERMADEC ISLANDS
A strong earthquake of M 6.1 also occurred near the IDL today in the area of Samoa and northern Tonga.
NEIC reported it was felt with maximum intensity V in Tualaele Northwest Upolu, Samoa and IV in American Samoa, Talimatau, Niusuatia and III in Apia, Vavau and II in Sataoa Uta.
This is the strongest earthquake in Samoa within about 200 km of this epicenter
since an M 6.3 on March 22, 2026. At the time this summary noted:
"... The onset of these geomagnetic storms coincided with a strong swarm
of strong earthquakes on the geomagnetic equator in Samoa and Tonga today.
storm was accompanied by an M 6.2 in the area of Samoa and Tonga.
The M 6.2 in Samoa was followed by a series of moderately strong to strong
aftershocks in the area including an M 5.8, 6.2 and M 6.3 later in the
day of March 22, 2026. NEIC reported intensity II in American Samoa for these events. The
last earthquake within about 200 km of today's epicenter with M>=6.2 occurred
as an M 6.7 on December 4, 2022 and prior to that an M 6.8 on November 4, 2017.
But these three events of M>=6.2 represent the strongest series in the area of
Samoa since in at least the past 35 years. These events were generally associated with sudden commencement
of further geomagnetic storms. At the time of the M 6.7 on December 4, 2022
this summary noted:
"The strongest earthquake in the world today was an M 6.7 in the Samoa region of the southwestern Pacific. NEIC reported maximum intensity IV in Samoa at Apia with III in Aua, Aoa, Neiafu, Ofa Manu'a, American Samoa and in Tonga at Ahoa Hahake Wallis and Futuna and in Tofoa-Koloua, Tongatapu.
This is the strongest earthquake in Samoa of equal or larger magnitude within about 200 km of this epicenter
since an M 6.8 on November 4, 2017 and an M 6.7 on June 29, 2014. The last event
of significantly larger magnitude in Samoa was an M 8.0-8.1 on September 9, 2009.
Forecasts 148907 and 148626 had expected today's activity within about 100 km
in the area of Samoa was likely in late November or early December, 2022.
Today's M 6.7 is a continuation of the strong seismic enhancement in Samoa, Tonga
and Fiji which began in mid-November, 2022." (December 4, 2022)
The initial M 6.2 in Samoa and Tonga occurred at a longitude which was
near local solar noon when the geomagnetic storm initiated and was
probably promoted by energy from that source. Samoa is located on the geomagnetic
equator where such effects maximize at the start of such storms.
These earthquakes in Samoa and Tonga are located at the sixth node (60 degrees)
from the South Geomagnetic Pole and at 101 degrees from the north geomagnetic
pole and at the fifth node (72 degrees) from Kamchatka and Malaysia and was
probably promoted by the commencement of the geomagnetic storm and constructive energy
interference from Kamchatka and Malaysia." (March 22, 2026)
It too was probably promoted by strong tidal stresses with the new moon (see above).
This epicenter was probably promoted by geomagnetic storms which occurred
about the time of its occurrence. It lies on the geomagnetic equator and is
located at 102 degrees from the North Geomagnetic Pole and at the sixth
node (60 degrees) from the South Geomagnetic Pole and the Molucca Sea. It is
also at the fifth node (72 degrees) from Malaysia and at the seventh node (52 degrees)
from Typhoon Sinlaku and may have been promoted by energy from those sources.
O: 19APR2026 17:34:47 15.1S 173.6W ML=6.1 NEIC TONGA/SAMOA
O: 19APR2026 17:34:49 15.2S 173.5W MW=6.1 EMSC TONGA
NEIC reported an earthquake of M 3.4 in Hawaii was felt with intensity up to II-III in the area(s) of Hawaii in Captain Cook and Naalehu.
This event occurred within minutes of local solar noon and may have been
promoted by tidal and/or geomagnetic stresses which maximize near this hour.
O: 19APR2026 22:31:02 19.0N 155.3W ML=3.4 NEIC HAWAII
O: 19APR2026 22:31:01 19.1N 155.4W ML=3.5 EMSC ISLAND OF HAWAII, HAWAII
A moderate aftershock of M 4.7 hit the region of western Nevada today. NEIC reported it was widely felt in western Nevada and California with IV in Nevada at Silver Springs and III in Washoe Valley, Fallon, Wadsworth, Yerington, Sparks, Carson City and in California at Sutter Creek, Markleeville, Foresthill.
EMSC reported moderate shaking in Nevada and California at Dayton, Fallon, Virginia City, Sparks, and Reno.
NEIC reported an aftershock of M 3.0 in Nevada was felt with intensity up to II-III in the area(s) of Nevada at Fernley and Fallon.
At the time of the mainshock of M 5.7 on April 14, 2026, this summary noted:
A moderately strong earthquake of M 5.7 occurred today in northwestern Nevada.
More than 6000 reports of felt activity for this event were reported to NEIC. These
included maximum intensity up to VII in the epicentral area; VI in Nevada at Silver Sprints; V in Fallon, and Yerinton; IV in Fernley, Dayton, Sparks, an in California at Mokelumne, Doyle, Alta and Honewood.
A series of light aftershocks up to M 4.0 were also recorded and many were felt.
EMSC reported it was felt with strong intensity in Nevada at Fallon, Virginia City, Sparks, Carson City, Spanish Springs, Reno, East Valley, Genoa, Mogul, Gardnerville Ranchos, and in California at Truckee, Foresthill, Auburn, Deer Park, Sonora, Rancho Cordova, Linda, Sacramento, Woodbridge, Lodi and lightly as far as 200 km from the epicenter in Oakley.
NEIC reported intensity up to VII in the epicentral area of Fallon. This is the
strongest earthquake within about 150 km of this epicenter since an M 5.8 on December 9, 2024.
The last event in the area with significantly larger magnitude was an M 6.0
on July 8, 2021. At the time of the December, 2024 earthquake this summary
noted:
"A moderately strong M 5.8 hit the region of northern Nevada near the California border today. It was followed by a strong series of light aftershocks.
NEIC reported maximum shaking of VI was felt in Nevada at Dayton, Fallon, Fernley, Minden and III in Gardnerville, Glenbrook, Hawthorne, Lovelock, Indian Sprints, Austin.
Preliminary reports do not indicate any major damage with this earthquake.
Minor damage such as items fallen from grocery shelves did occur near the
epicenter. More than 12,000 responded to NEIC that they had felt this earthquake.
The last earthquake within about 200 km of this epicenter in northern Nevada with
M>=5.8 occurred on July 8, 2021 with M 6.0. The only other event in the region
in the past 35 years was an M 6.1 on September 12, 1994. At the time of the July, 2021
event this summary noted:
"The earthquake of M 6.0 in California was preceded about an hour earlier by an M 4.4
in Southeastern Alaska. NEIC reported this earthquake was felt with intensity IV in Alaska at Haines, Skagway and II-III in Elfin Cove, Gustavus, Hoonah, Juneau, Douglas, and in Whitehorse, Yukon, Canada.
Several other indicators had suggested that a strong earthquake was imminent in
California at this time. For example when a light earthquake occurred in western
South Dakota on June 16 ..." (July 8, 2021)
Some indication of a strong enhancement of regional seismicity inland from
major earthquakes off northern California has previously been commented on
in this summary. For example an M 4.2 in Utah - the second strongest earthquake
in Utah in the past four years - occurred minutes after the M 7.0 in California.
At the time this summary noted:
"The mainshock off northern California was also accompanied by an M 4,2 several minutes
later in Utah. This coincidence has been noted in this summary previously.
For example when an M 5.7 occurred in northern Utah on March 18, 2020 and was followed
several hours later by an M 5.2 off the coast of northern California this summary noted:
"A moderate earthquake was also felt in Northern California today. This event of M 5.0-5.2 occurred near the coast and was felt with maximum intensity VI in Ferndale and Scotia according to data from NEIC. Intensity V shaking occurred in California at Rio Dell, Fortuna and Eureka and IV in Petrolia and Hydesville with lesser shaking in Lleta, Carlotta and Myers Flat. Light shaking was reported as far as Central California and southern Oregon. Several light aftershocks followed.
This is probably a regional aftershock of the M 5.8 which hit the area to the
west on March 9, 2020 in a regional activation from Alaska to southern California."
This summary had noted this at the time" (March 18, 2020)
The mainshock in Nevada may have been promoted by a C2.3 solar flare (#5700)
which was finishing up at the time of this earthquake." (December 9, 2024)
This summary had provided some warning that such an event was possible
at this time in the previous issue of this summary as:
"A strong geomagnetic excursion occurred on the GOES 19 magnetometer on April 13, 2026
at about 07:40-08:00 UT. This could affect areas near 60 East longitude and 120 West
longitude including area of Pakistan and Iran in the East and California
and western North America in the west. Expect moderate enhancement in
seismicity during the several hours after this change in geomagnetic field strength." (April 13, 2026)
Today's earthquake was within a couple of minutes of local solar midnight when
this geomagnetic effect peaked near 07:56 UT (00:00 UT local solar time) on GOES 19 Magnetometer
when an arcjet stabilizing maneuver corrected the satellite position.
This epicenter is at 108 degrees from the M 7.6 in the Molucca Sea of April 1. 2026.
This is at the distance where reflected and refracted seismic energy returns
to the surface following major earthquakes such as the event in the Molucca Sea.
The far-field forecast for Molucca had identified potential triggering of enhanced seismicity
in this area as:
"Inner shadow zone edge (101-110 degrees)
Molucca Sea to Idaho, Los Angeles, Vancouver B.C., Oregon, Washington, San Francisco, Coast of Northern California, Adriatic Sea, Mt. Etna, Italy, Serbia, British Columbia, Canada, Oregon, Nevada, Northern and Central California, Greece, Adriatic Sea, Crete, East Pacific Rise, " (April 1, 2026), April 14, 2026
Today's event is also at the fifth node (72 degrees) from Honshu and may
have been associated with the M 7.4 in that region today.
Following is a listing of aftershocks today in Nevada of M>=3. A more complete
listing can be found in the "DATA" section of this summary.
O: 19APR2026 17:15:01 39.3N 119.0W ML=3.0 NEIC NEVADA
O: 19APR2026 14:39:16 39.3N 119.0W ML=4.7 NEIC NEVADA
O: 19APR2026 12:43:30 39.3N 119.1W Mw=4.2 EMSC NEVADA
O: 19APR2026 12:45:15 39.3N 119.1W ML=3.3 EMSC NEVADA
O: 19APR2026 14:39:17 39.3N 119.1W Mw=4.7 EMSC NEVADA
O: 19APR2026 14:47:11 39.3N 119.1W ML=3.0 EMSC NEVADA
O: 19APR2026 17:15:01 39.3N 119.0W ML=3.0 EMSC NEVADA
NEIC reported earthquakes of M 3.3 and M 3.7 occurred among others in Utah was felt with intensity up to II-III in the area(s) of Utah near Kanosh.
O: 19APR2026 13:47:13 38.7N 112.4W ML=3.3 NEIC UTAH
O: 19APR2026 11:45:29 38.7N 112.5W ML=3.2 EMSC UTAH
O: 19APR2026 11:48:09 38.7N 112.5W ML=2.6 EMSC UTAH
O: 19APR2026 12:35:48 38.7N 112.5W ML=2.5 EMSC UTAH
O: 19APR2026 13:47:13 38.7N 112.5W ML=3.3 EMSC UTAH
O: 19APR2026 14:43:47 38.7N 112.5W ML=3.7 EMSC UTAH
O: 19APR2026 14:53:47 38.7N 112.5W ML=2.5 EMSC UTAH
O: 19APR2026 15:55:13 38.7N 112.5W ML=2.5 EMSC UTAH
O: 19APR2026 16:29:24 38.7N 112.5W ML=2.5 EMSC UTAH
EMSC reported an earthquake of M 5.2 in Timor, Indonesia was felt with intensity up to IV in the area(s) of Timor, Indonesia in Dili.
O: 20APR2026 05:19:36 8.0S 124.3E ML=5.2 EMSC TIMOR, INDONESIA
O: 20APR2026 05:19:35 8.0S 124.3E MB=5.2 EMSC KEPULAUAN ALOR, INDONESIA
SEISMIC EFFECTS OF TROPICAL CYCLONES
Some seismicity may be affected by weather due to wind, tidal surge and air pressure systems effects of the continental mass compared with adjoining plate masses. During the tropical storm season in the Northern Hemisphere we keep an eye on tropical storms which may affect seismicity according to our models. Currently the following tropical storms appear to have potential to affect seismicity in the coming week:
TYPHOON SINLAKU (04W)
---- ------- ---------- -------- ----- ------ ------- ---------------
TYP SINLAKU 2026-04-20 00:00 UT 28.7N 156.1E 65 kts East of Honshu, Japan
Typhoon Sinlaku (04W) continued today in the region east of Honshu, Japan as a Typhoon with winds up to 65 kts. It is expected to track to the northeast over the next several days and could help trigger seismicity in Honshu, Japan during this period. The antipode at 29S 24W is near the southern mid-Atlantic Ridge and could see minor seismic enhancement at this time,
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of April 19, 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 when a flare occurred and may also have
been affected by SFE. These are not identified here.
SOLAR FLARES
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
No solar flares of C- or higher class were reported by SWPC today.
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: unsettled April 22 and active April 20-21. Solar M-flare chance: 5% X-class: 1% proton storm: 1%
AP Indicies: global: 23, high: 41, mid-latitude: 16, time of max AP: 06:00 UT; Max AP: 7 Global Kp 5.67 0500-0700, April 19; Sunspot Number: 35; Radio Flux: 105
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