Because this summary is often behind schedule updates to the current date are being added here to make it more relEvAnt to current conditions
May 29, 2026
Notable earthquakes and events:
Strong excursions in the local geomagnetic field at the GOES-19 satellite were
recorded on that magnetometer at 02:30-03:00 UT and again at 04:52 UT. This
later anomaly nearly doubled the field strength (from 50 to 100 nT) in a couple
of minutes and required an arcjet correction to stabilize the orbit. The arcjet
maneuver occurred at 05:53 UT. By 06:20 UT the orbit was stabilized and normal
operating conditions at GOES-19 resumed. An M 4.4 earthquake occurred at 04:55 UT
in Jujuy, Argentina within minutes of local solar midnight and may have
been related this geomagnetic excursion. The GOES-19 satellite is located
in a geostationary orbit at 72.5W so the event in Argentina (directly
under this at 66W) would have experienced this magnetic excursion at this
time. Earthquakes of M 2.6 in Missouri and an M 4.0 in the Gulf of California at 03:42 UT occurred with a lesser
geomagnetic excursion registered on the GOES-18 magnetometer which peaked at
03:40 UT (GOES 18 is at 137 West longitude). This behavior has been documented in the past in previous issues
of this summary.
The earthquake in Argentina also occurred near the peak of a strong C6.1 solar
flare and, as it occurred within minutes of local midnight in Argentina
may have been promoted by SFE associated with that flare. Data for this flare
from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0450 0508 0524 C6.1 (May 29, 2026) 5.6E-03
Jujuy Argentina M 4.4 04:55 UT
O: 29MAY2026 04:55:51 22.6S 66.2W ML=4.4 NEIC JUJUY, ARGENTINA
"The full moon will arrive on May 31, 2026 at 08:45 UT. Longitudes at local solar noon were near 50 East while those at local solar midnight are near 130 West longitude. These include Hawaii and areas of eastern Alaska and western Canada and to a lesser extent areas off the coast of Oregon and California while in the east they include Eastern Turkey, Iran as well as Ethiopia and areas off southern Africa and east Africa. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time." (May 27-29, 2026)
NEIC reported an earthquake of M 5.3 near Urumqi, China was felt with intensity up to II-III in the area(s) of near Urumqi, China may have been felt in Turpan, China.
This was the largest earthquake in the past 24 hours in the world. It occurred
near the peak of a strong M1.1 solar flare, the strongest flare of the past
two days and may have been promoted by SFE associated with that flare
as it occurred within minutes of local solar noon when such effects maximize.
Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
XXXX 0640 0704 0724 M1.1 (May 29, 2026) 2.6E-02
Northern Xinjiang, China M 5.3 06:55 UT
O: 29MAY2026 06:55:52 42.2N 88.3E ML=5.3 NEIC NORTHERN CHINA
NEIC reported an earthquake of M 2.6 in Western Texas was felt with intensity up to II-III in the area(s) of Western Texas in Stanton.
O: 29MAY2026 06:22:02 32.1N 101.9W ML=2.6 NEIC WESTERN TEXAS
NEIC reported an earthquake of M 2.6 in Missouri was felt with intensity up to II-III in the area(s) of Missouri near Williamsville.
This event occurred at the beginning of a geomagnetic excursion event
recorded on GOES-19 magnetometer and may have been promoted that.
This epicenter is at the fourth node (90 degrees) from Honshu, Japan and
may have been promoted by energy from that source.
O: 29MAY2026 03:58:44 37.0N 90.4W ML=2.6 NEIC MISSOURI
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 at Johannesburg.
O: 29MAY2026 02:00:57 35.3N 117.8W ML=3.3 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 4.3 in Bosnia and Herzegovina was felt with intensity up to II-III in the area(s) of Bosnia and Herzegovina in Croatia at Dubrovnik-Neretva at Dubrovnik and Mlini.
EMSC reported strong shaking at Bileca, Ljubinje, Trebinje, Ravno, Gacko, Stolac, and in Croatia at Mokosica, Zaton, Cibaca, Petraca, Brasina, Mlini, Dubrovnik, Cavtat, Zvekovica, and as far as Montenegro.
This epicenter is at 103 degrees from the epicenter of the M 6.9 in Chile of
May 25 and was likely promoted by energy from that source. A pair of strong
earthquakes yesterday occurred south of Australia and were also at 103 degrees
from Chile (see previous issue of this summary). This event occurred near
local solar midnight and may also have been promoted by tidal and/or geomagnetic
effects.
The far-field seismicity forecast from Antofagasta, Chile (published in previous
issues of this summary had expected enhanced seismicity in this region as:
"Inner shadow zone edge (101-110 degrees)
Antofagasta, Chile to Indian-Antarctic Ridge south of Australia, Albania, Greenland Sea, Greece, Denmark, Slovenia, Adriatic Sea, Central, eastern Alaska, Italy, South Indian Ocean, Gulf of Alaska, Poland, Tonga/Fiji/Samoa, Madagascar, Lake Victoria, Romania" (May 27-28, 2026)
O: 28MAY2026 22:00:13 42.8N 18.3E ML=4.3 NEIC BOSNIA AND HERZEGOVINA
NEIC reported an earthquake of M 3.1 in Northern Utah was felt with intensity up to II-III in the area(s) of Northern Utah in Salt Lake City and Logan.
O: 28MAY2026 20:58:55 41.9N 112.8W ML=3.1 NEIC NORTHERN UTAH
NEIC reported an earthquake of M 5.3 in the Revilla Gigedo Islands region of Mexico was felt with intensity up to II-III in the area(s) of the Revilla Gigedo Islands region of Mexico.
This was the largest event of many located today at 18-19 North latitude
including a series in Tabasco, Mexico, the northern Mariana Islands, the Philippines
and Laos among others. This is the sub-solar latitude on May 29. It can be
argued that enhanced vertical tidal forces at this time can help promote
larger earthquakes at sub-solar latitudes.
This epicenter is at the fourth node (90 degrees) from Honshu and at the sixth node
from Antofagasta, Chile (60 degrees) and may have been promoted by constructive
energy interference from those sources.
O: 28MAY2026 16:18:09 19.6N 109.4W ML=5.3 NEIC REVILLA GIGEDO ISLANDS REGION
NEIC reported an earthquake of M 3.7 in Nevada was felt with intensity up to II-III in the area(s) of Nevada in Reno, Yerington, Silver Springs, Fallon, Fernley, Glenbrook andin California at Camino and Placerville.
This continues a month-long series in this area.
O: 28MAY2026 11:48:35 39.3N 119.4W ML=3.7 NEIC NEVADA
EMSC reported a series of earthquakes of M 4.3, M 4.1 and M 4.0 in Tabasco, Mexico was felt with intensity up to IV in the area(s) of Tabasco, Mexico at Villahermosa.
These are events at sub-solar latitudes today (see above in regard to
Revilla Gigedo M 5.3 for more details).
This epicenter is at 103 degrees from Honshu, Japan and Vanuatu and at the
fourth node (90 degrees) from Tonga and may have been promoted by energy
from those sources.
O: 29MAY2026 09:10:32 18.2N 92.8W ML=4.3 EMSC TABASCO, MEXICO
O: 28MAY2026 23:53:39 18.4N 92.9W ML=4.1 EMSC TABASCO, MEXICO
O: 28MAY2026 23:55:00 18.3N 92.9W ML=4.0 EMSC TABASCO, MEXICO
EMSC reported an earthquake of M 4.6 in Kyrgyzstan was felt with intensity up to IV in the area(s) of Kyrgyzstan in Osh and Aravan and in Uzbekistan at Andijon, and in Kazakhstan at Almaty and in Khujand, Tajikistan.
This epicenter is at 143 degrees from Antofagasta, Chile (node 5) and 51 degrees (node 7)
from Honshu, Japan and 103 degrees (node 7) from Vanuatu and may have been promoted
by constuctive interference of eneryg from those sources.
O: 29MAY2026 08:15:11 41.6N 73.8E ML=4.6 EMSC KYRGYZSTAN
EMSC reported an earthquake of M 3.5 in Martinique was felt with intensity up to IV in the area(s) of Martinique in Saint Lucia at Bisee.
O: 28MAY2026 14:08:01 14.6N 60.6W ML=3.5 EMSC MARTINIQUE REGION, WINDWARD ISL.
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 JANGMI (06W)
---- ------- ---------- -------- ----- ------ ------- ---------------
TS JANGMI 2026-05-29 00:00 UT 15.9N 132.8E 50 kts North Pacific
TS Jangmi continued today in the north Pacific near the island of Yap with winds up to 50 kts. It is expected to track to the northwest over the next five days reaching the Ryukyu Islands with winds up to 100 kts around May 31 to June 1 and continuing into Kyushu, Japan. This is the first cyclone of the season to threaten the western Pacific subduction zone. First cyclones often trigger significant seismic and volcanic activity where stress has built up since the last round of seasonal storms. A moderate to large earthquake in the Central Ryukyu Islands north to Honshu, Japan could be anticipated at the end of May or early June as this storm impacts the area. The antipode is currently at 10S 43W, a non-seismic area near the coast of Brazil.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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)
-------------------------------------------------------------------------
XXXX 0640 0704 0724 M1.1 (May 29, 2026) 2.6E-02
Northern Xinjiang, China M 5.3 06:55 UT
Oaxaca M 4.0 07:14 UT
Central California M 2.2 06:39 UT
XXXX 0524 0537 0550 C7.6 (May 29, 2026) 7.6E-03
Gulf of California M 4.2 05:56 UT
XXXX 0450 0508 0524 C6.1 (May 29, 2026) 5.6E-03
Jujuy Argentina M 4.4 04:55 UT
5710 0752 0800 0807 C1.1 (May 28, 2026) 1.0E-03
Flores Sea M 4.1 08:06 UT
5760 0958 1009 1020 C1.8 (May 28, 2026) 2.1E-03
Western Texas M 2.1 10:10 UT
Mindanao M 4.4 10:44 UT
5840 1509 1516 1518 C3.2 (May 28, 2026) 1.2E-03
Coquimbo M 4.3 15:30 UT
South Sandwich Is. M 4.8 15:08 UT
5850 1628 1637 1641 C1.5 (May 28, 2026) 1.1E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: active May 31 unsettled May 29-30. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 13, high: 16, mid-latitude: 13, time of max k: 16:00-18:00 UT; Max k: 5 Global Kp 3.67 1700-1900, May 28; Sunspot Number: 161; Radio Flux: 145
May 28, 2026
Notable earthquakes and events:
A pair of strong M 6.0 earthquakes occurred today on the Indian-Antarctic Ridge
south of Australia. These events were not reported felt in this remote area.
Today's earthquake are of particular interest to this summary for two reasons.
First, the first event of M 6.0 occurred within a minute of local solar midnight.
Readers can compare the time of this earthquake at 14:51 UT with the time
of local solar midnight at the epicenter of this earthquake (14:53 UT).
The second M 6.0 occurred 10 minutes later and was closely associated
with the return of the core-mantle reflected PcS or PcP waves. Strong
aftershocks often occur with this time interval after the mainshock suggesting
dynamic triggering by body waves.
The second thing about these earthquakes in the Indian-Antarctic Ridge today
is that they occurred at 103.3 degrees from the epicenter of the M 6.9 that hit yesterday
in the region of Antofagasta, Chile. This is the distance at which much of
the seismic energy from a mainshock (in the form of body waves) returns to the
surface (with a minor correction for depth of the mainshock). This has a strong
energy signature at the surface at this distance. It is also the fifth node
(51.4*2) free earth oscillation. Combined these effects can help trigger
strong earthquakes at 103 degrees from the epicenter of major earthquakes.
This has been shown on multiple occasions in this summary and is followed
on a daily basis in this summary. The area near 103 degrees from Antofagasta
is more seismic than many. The expected areas of enhanced seismicity associated
with the 103 degree distance from Antofagasta, Chile are given in this summary as:
"Inner shadow zone edge (101-110 degrees)
Antofagasta, Chile to Indian-Antarctic Ridge south of Australia, Albania, Greenland Sea, Greece, Denmark, Slovenia, Adriatic Sea, Central, eastern Alaska, Italy, South Indian Ocean, Gulf of Alaska, Poland, Tonga/Fiji/Samoa, Madagascar, Lake Victoria, Romania" (June 3, 2014 , May 27-28, 2026)
It is therefore of some interest that the strongest earthquake in the past 35
years near today's epicenter in the Indian-Antarctic Ridge was an M 6.4-6.6 on June 11, 2000.
This occurred at 103 degrees from an M 7.2 in the Antofagasta, Chile area
less than a month earlier on May 12, 2000 also at an intermediate depth.
The last earthquakes of M>=6 within about 300 km of today's epicenters
occurred as an M 6.3 on October 11, 2023 and as an aftershock of M 6.0 on October 13, 2023.
An M 6.0 also occurred on August 21, 2019. At the time of the earthquakes
in October, 2023, this summary noted:
"The strongest earthquakes in the world today occurred in the southern oceans with an M 5.3 in the South Sandwich Islands
and an M 6.0 south of Australia on the Indian-Antarctic Ridge, the largest event
of the day. Neither of these was reported felt in their remote and respective epicentral areas.
The earthquake in the Indian-Antarctic Ridge occurred within about an hour of
local solar noon while the event in the South Sandwich Islands was within about
an hour of local solar midnight. Both may have been promoted by strong tidal stresses
associated with the new moon and solar eclipse of October 14 ...
The earthquake in the western Indian-Antarctic Ridge occurred directly north of the
M 6.3 in the Macquarie Island region which occurred yesterday (October 11, 2023). It is probably
a regional aftershock of that event. No other earthquakes within about 300 km
of this epicenter with M>=6 have been recorded since 1990. The largest such event
previous to today's M 6.0 was the M 6.4 yesterday and an M 5.8 on March 24, 2007. When an M 5.5 hit
north of today's epicenter on November 2020, this summary noted:
"The strongest earthquake in the world, and the only event of M>=5 today was an M 5.7 in the Macquarie Island area south of Australia.
This continues a series of moderate to moderately strong earthquakes in this area
which began several days ago and included event of M 4.6 on November 9; an M 5.7 on November 13 and and M 4.4 on November 14.
These events occurrred about 1000 km to the east of today's activity. The last activity
within about 300 km of today's event with M>4 occurred on August 27, 2020 with M 4.8.
The last earthquake of M>=5.7 within about 500 km of today's epicenter was an
M 6.0 on August 21, 2019 and and M 6.5 April 18, 2019 and M 5.9 February 27, 2016." (November 20, 2020, October 13, 2023)
In addition to being at 103.5 degrees (node 7) from Antofagasta, Chile this
epicenter is about 1000 km (13 degrees) from the South Geomagnetic Pole and
at the fourth node (90.0 degrees) from Honshu, Japan and the seventh node (52 degrees
from the Molucca Sea and may have been promoted by energy from those sources
as well.
O: 28MAY2026 14:51:04 50.5S 139.4E ML=6.0 NEIC WESTERN INDIAN-ANTARCTIC RIDGE
O: 27MAY2026 14:51:06 50.5S 139.4E MW=6.0 EMSC WESTERN INDIAN-ANTARCTIC RIDGE
O: 27MAY2026 15:01:12 50.5S 139.4E MW=6.0 EMSC WESTERN INDIAN-ANTARCTIC RIDGE
O: 28MAY2026 15:01:11 50.5S 139.3E ML=6.0 NEIC WESTERN INDIAN-ANTARCTIC RIDGE
The full moon will arrive on May 31, 2026 at 08:45 UT. Longitudes at local solar noon were near 50 East while those at local solar midnight are near 130 West longitude. These include Hawaii and areas of eastern Alaska and western Canada and to a lesser extent areas off the coast of Oregon and California while in the east they include Eastern Turkey, Iran as well as Ethiopia and areas off southern Africa and east Africa. These and surrounding areas are the most likely to see tidally enhanced seismicity at this time.
DISTANCE RELATIONS BETWEEN EARTHQUAKES
Statistical evidence indicates that some triggering or promotion forward in time can occur in regions which are under high stress due to additional stress events of small size. Among these are surface and body waves passing through a region. Triggering may be dynamic with the promoted earthquake occurring at the same time as the stress event or delayed with an earthquake occurring later in time but still related to the stress event through water lubrication or other various geophysical effects on the faults. We have argued in this report for the past 35 years that this effect is most observable where the seismic waves are largest. In general this occurs at distances from the rupture ends of the earthquake producing those waves (mainshock) which we have termed nodal distances. These are defined by the formula D=360*m/n where D is the distance in degrees and m<=m where n an m are small integers. These are also the locations of the maximum corrections to magnitude in the standard Jeffreys-Bullen tables. In addition there is focusing of seismic energy from reflections and refractions of f the core-mantle and the inner-outer core boundary of the earth. This focuses energy at the surface in the distance between 101 and 108 degrees (core-mantle) and 141-148 degrees (inner-outer core boundary). In this report we monitor seismicity at these distances following major earthquakes as experience has shown that strong and/or unusual earthquake are much more likely to occur at these distance from the mainshock.
The following areas may see enhanced seismicity at nodal distances and areas
of high seismic return energy to the surface following the M 6.9 in Antofagasta,
Chile.
Antipodal (~180 degrees)
Antofagasta Chile to Southern China, western Philippines, Vietnam
Outer shadow zone edge (141-148 degrees)
Antofagasta, Chile to Lake Baykal, Guam, Mariana Islands, Micronesia, New Guinea, Ceram, Northern Honshu, Japan, Tajikistan, Afghanistan, Northern Mariana Is., India, Sumba, Siberia, Java, Hindu Kush,
Node 3 (120 degrees)
Antofagasta, Chile to Owen Fracture Zone, Solomon Is, Rat Islands, Caucasus, Australia, Eastern Turkey,
Inner shadow zone edge (101-110 degrees)
Antofagasta, Chile to Indian-Antarctic Ridge south of Australia, Albania, Greenland Sea, Greece, Denmark, Slovenia, Adriatic Sea, Central, eastern Alaska, Italy, South Indian Ocean, Gulf of Alaska, Poland, Tonga/Fiji/Samoa, Madagascar, Lake Victoria, Romania
Node 4 (90 degrees)
Antofagasta, Chile to New Zealand, France, Andora, SE Alaska, Algeria, Balleny Is.
Node 5 (72 degrees)
Antofagasta, Chile to Azores, Los Angeles, California, Utah, Lake Isabella, CA, Yellowstone, Quebec, Azores, southern East Pacific Rise
Node 6 (60 degrees)
Antofagasta, Chile to Western Texas, Oklahoma, Missouri/Tennessee, Gulf of California, Canary Is.
Node 7 (52 degrees)
Antofagasta, Chile to Central Mid-Atlantic, Central/western Mexico, South Sandwich Is,
Node 8 (45 degrees)
Antofagasta, Chile to Puerto Rico, Virgin Islands, Dominican Republic, East Pacific Rise, Central Mid-Atlantic, South Sandwich Is,
The sun was at its most active sunspot period in the past month today. NOAA
gives the sunspot area as 1325 10E-6 Hemis. with 165 SESC Sunspot number
and radio flux of 142 at 10.7 cm.
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 in El Cajon and Imperial Beach, and in Rosarito and Ensenada, Baja California.
O: 28MAY2026 09:41:05 32.2N 117.0W ML=3.3 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 5.2 in Andreanof Islands, Aleutians, Alaska was felt with intensity up to II-III in the area(s) of Andreanof Islands, Aleutians, Alaska in Adak.
This earthquake 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 third node (120 degrees) from the south geomagnetic
pole and at the 10th node (36 degrees) from the north geomagnetic pole
and may have been promoted by energy from those sources.
O: 28MAY2026 00:25:21 51.8N 175.9W ML=5.2 NEIC ANDREANOF ISLANDS, ALASKA
O: 28MAY2026 00:25:22 51.8N 175.9W MB=5.2 EMSC ANDREANOF ISLANDS, ALEUTIAN IS
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 in Homer.
This epicenter is at 105 degrees from Antofagasta, Chile and may have been promoted
by energy from that source.
O: 28MAY2026 00:16:48 60.3N 150.8W ML=3.4 NEIC SOUTHERN ALASKA
O: 28MAY2026 00:16:46 60.2N 150.9W ML=3.4 EMSC KENAI PENINSULA, ALASKA
NEIC reported an earthquake of M 2.8 in Washington State was felt with intensity up to II-III in the area(s) of Washington State in Bremerton, Alalla, Tacoma, Seattle, Mercer Island, Renton, Port Orchard, Shelton, Vaughn and Gig Harbor.
This epicenter is at 103 degrees from the Molucca Sea and may have been promoted
by energy from that source.
O: 27MAY2026 22:48:56 47.4N 122.7W ML=2.8 EMSC PUGET SOUND REGION, WASHINGTON
O: 27MAY2026 22:48:57 47.4N 122.7W ML=2.8 NEIC WASHINGTON STATE
NEIC reported an earthquake of M 3.4 in Western Texas was felt with intensity up to II-III in the area(s) of Western Texas near Hope, New Mexico.
O: 27MAY2026 15:49:30 31.6N 104.2W ML=2.0 EMSC WESTERN TEXAS
O: 27MAY2026 17:36:32 31.6N 104.1W ML=2.5 EMSC WESTERN TEXAS
O: 27MAY2026 13:01:39 31.7N 103.6W ML=2.1 EMSC WESTERN TEXAS
O: 27MAY2026 17:53:45 32.6N 104.6W ML=3.4 EMSC NEW MEXICO
O: 27MAY2026 17:53:45 32.6N 104.6W ML=3.4 NEIC WESTERN TEXAS
NEIC reported an earthquake of M 2.7 in Mammoth Lakes, California was felt with intensity up to II-III in the area(s) of Mammoth Lakes, California in Bishop.
O: 27MAY2026 10:13:07 37.4N 118.7W ML=2.9 NEIC MAMMOTH LAKES, CALIFORNIA
O: 27MAY2026 10:13:07 37.5N 118.7W ML=2.8 EMSC 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:
TROPICAL DEPRESSION JANGMI (06W)
---- ------- ---------- -------- ----- ------ ------- ---------------
TD JANGMI 2026-05-28 00:00 UT 13.0N 135.3E 40 kts North Pacific
TD Jangmi continued today in the north Pacific near the island of Yap with winds up to 40 kts. It is expected to track to the northwest over the next five days reaching the Ryukyu Islands with winds up to 110 kts around May 31 to June 1 and continuing into Kyushu, Japan. This is the first cyclone of the season to threaten the western Pacific subduction zone. First cyclones often trigger significant seismic and volcanic activity where stress has built up since the last round of seasonal storms. A moderate to large earthquake in the Central Ryukyu Islands could be anticipated at the end of May or early June as this storm impacts the area. The antipode is currently at 10S 43W, a non-seismic area near the coast of Brazil.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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)
-------------------------------------------------------------------------
XXXX 0958 1009 1020 C1.8 (May 28, 2026) 2.1E-03
Western Texas M 2.1 10:10 UT
Mindanao M 4.4 10:44 UT
5420 0149 0159 0203 C1.9 (May 27, 2026) 1.3E-03
5470 1207 1216 1219 C3.4 (May 27, 2026) 1.6E-03
Samar Philippines M 4.3 12:07 UT
Antofagasta M 4.4 12:23 UT
5480 1320 1323 1329 C2.8 (May 27, 2026) 1.3E-03
Chiapas M 4.2 13:31 UT
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet May 30 unsettled May 29 active May 28. Solar M-flare chance: 40% X-class: 5% proton storm: 5%
AP Indicies: global: 11, high: 12, mid-latitude: 12, time of max k: 06:00-08:00 UT; Max k: 4 Global Kp 3.33 2100-2400, May 27; Sunspot Number: 165; Radio Flux: 142
May 27, 2026
Notable earthquakes and events:
New data has been published on the events at the time of the M 6.9 in
Antofagasta, Chile reported on in the previous issue of this summary.
In the previous issue it was noted that a proton storm had occurred
with its origin very near the time of the M 6.9 in Chile as:
"A strong geomagnetic storm began about 21:50 UT-22:00 UT on May 25, 2026. This involved proton
flux exceeding the SWPC 10 MeV warning threshold with more than 10 particles/flux unit (pfu)
The flux event in protons peaked around 01:10 UT on May 26 with 23.8 pfu. Strong enhancement
of protons were also observed at energy levels of MeV>=50 and MeV>=100. This storm
was reated as a minor S1 Solar Radiation Storm with minor impacts on HF radio through polar regions. Enhanced electron
flux began about 17:00 UT on May 25 (as measured on the GOES-18 Electron flux instrument
and stayed near the alert threshold until about 23:20 UT. The GOES 19 magnetometer
at 72 West longitude recorded a strong decline in global geomagnetic strength
from about 21:30 UT to 22:50 UT indicating the beginning of the proton storm at this longitude. For the day solar radio flux at 10.7 cm
was the highest since May 3-4 and the SESC Sunspot number at 132 was the highest
also once May 3-4, 2026. ..." (May 26, 2026)
Further examination of the data from the NOAA/NASA ACE satellite (which measures interplanetary solar wind
and magnetic field strength) at a Lagrange point
of the earth indicates that at 21:50-21:53 UT on May 25, the interplanetary
magnetic field (IMF) registered an inflection point. Prior to this time
the magnetic field strengh had gradually been declining for hours. At this
time (date in 3 minute intervals) a sudden spike in Bz GSM field strength occurred
followed by a return to a value above the previous background and continued
for 17 hours at an increasing (as opposed to a decreasing) field intensity.
At the same time a major rim (or far-side) solar flare erupted beginning
at 21:50 UT. This event is clear on the solar coronograph (CCOR-1). It
appears likely that events related to this solar flare were instrumental
in the following proton storm minutes later and possibly to the simultaneous
earthquake of M 6.9 in Chile at 21:52 UT. The exact structure of this
causality remains to be determined.
The Sunspot number of 148 today was surpassed in the past month only on May 1, 2026 when
the sunspot number was 158. An EMP was seen on the GOES 18 magnetometer
beginning at about 21:14 UT. An arcjet maneuver was performed at 21:20 UT
and normal operations of the GOES-18 satellite instruments resumed at 22:19 UT.
An earthquake of M 3.8 occurred with this EMP off North Island, New Zealand
with M 3.8. Other areas showing seismic activity at this time were southern
California, western Turkey and the Canary Islands among others.
NEIC reported an earthquake of M 4.6 in Coquimbo, Chile was felt with intensity up to II-III in the area(s) of Coquimbo, Chile.
O: 27MAY2026 04:17:23 30.6S 71.9W ML=4.6 NEIC COQUIMBO, CHILE
O: 27MAY2026 04:17:23 30.6S 71.7W MW=4.8 EMSC OFFSHORE COQUIMBO, CHILE
NEIC reported aftershocks of M 4.7-4.9 and M 5.1 in Antofagasta, Chile was felt with intensity up to II-III in the area(s) of Antofagasta, Chile
O: 27MAY2026 00:41:51 23.3S 69.2W ML=4.7 NEIC ANTOFAGASTA, CHILE
O: 27MAY2026 05:23:31 22.3S 68.7W MW=5.1 EMSC ANTOFAGASTA, CHILE
O: 27MAY2026 00:41:51 23.3S 69.1W Mw=4.9 EMSC ANTOFAGASTA, CHILE
NEIC reported earthquakes of M 5.0 and M 5.4 in Tonga were felt with intensity up to II-III in the area(s) of Tonga in Neiafu Vava'u.
This epicenter is at 103 degrees from the North Geomagnetic pole and may have
been promted by energy from that source.
O: 26MAY2026 19:25:11 17.3S 174.2W ML=5.0 NEIC TONGA
O: 26MAY2026 19:25:11 17.3S 174.2W MB=5.0 EMSC TONGA
O: 26MAY2026 19:12:32 17.6S 172.9W MB=5.4 EMSC TONGA REGION
O: 26MAY2026 19:12:31 17.7S 172.6W ML=5.4 NEIC TONGA
NEIC reported an earthquake of M 4.6 in Tarapaca, Chile was felt with intensity up to II-III in the area(s) of Tarapaca, Chile with II in Iquique and III in Calama, Antofagasta.
O: 26MAY2026 16:42:41 20.0S 69.2W ML=4.6 NEIC TARAPACA, CHILE
O: 26MAY2026 16:42:41 19.9S 69.2W MB=4.6 EMSC TARAPACA, CHILE
NEIC reported an earthquake of M 3.5 in Central Alaska was felt with intensity up to II-III in the area(s) of Central Alaska near Manley Hot Springs.
O: 26MAY2026 13:43:57 64.7N 150.8W ML=3.5 NEIC CENTRAL ALASKA
O: 26MAY2026 13:43:57 64.7N 150.8W ML=3.5 EMSC CENTRAL ALASKA
NEIC reported an earthquake of M 4.4 in GUAM was felt with intensity up to II-III in the area(s) of Guam at Mangilao, Hagatna, Santa Rita, Tamuning and Yigo.
EMSC reported moderate shaking in Guam at Piti Village and Santa Rita Village.
This epicenter is near the fifth node (72 degrees) from the North and South
geomagnetic poles and may have been promoted by constructive interference
of energy from those sources.
O: 26MAY2026 11:10:25 13.6N 144.7E ML=4.4 NEIC GUAM
O: 26MAY2026 11:10:25 13.6N 144.8E MB=4.4 EMSC GUAM REGION
NEIC reported an earthquake of M 4.9 South of Java was felt with intensity up to II-III in the area(s) of Java in Bali at Denpasar, Kuta and Ubud.
EMSC reported moderate shaking in Indonesia at Krajan, Negara, Pecatu, Banjar Sengguan, Banjar Kerobokan, Kangin, Banjar Gunungpande, Legian, KanginJimbaran, Denpasar, Karyadharma, Banjar Medura, Banjar Taman, Pegongan, Banjar Pande, Tebongkang, Ubud, Gianyar, and Biaslantang Kaler.
This earthquake occurred at the peak of solar flare 5360 and may have been
promoted by SFE from that flare. Data on this flare from SWPC follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5360 0827 0840 0848 C2.9 (May 26, 2026) 3.4E-03
Vancouver M 2.8 08:27 UT
Java M 4.9 08:39 UT
This epicenter is at 148 degrees from the earthquake in Antofgasta, Chile and may have
been promoted by energy from that source.
O: 26MAY2026 08:39:11 8.9S 113.8E ML=4.9 NEIC SOUTH OF JAVA
O: 26MAY2026 08:39:11 8.9S 113.8E MB=4.9 EMSC JAVA, INDONESIA
NEIC reported an earthquake of M 5.2 in the East Pacific Rise/Antarctic Ridge today
was not felt in this remote area. An M 6.6 occurred east of this several
days ago and the entire ridge appears to be somewhat unstable at this time.
Expect further moderate to large earthquakes along this ridge in the next
several days.
This epicenter is at 145 degrees from the North Geomagnetic Pole and
may have been promoted by energy from that source.
O: 26MAY2026 16:22:51 58.8S 152.6W MB=5.2 EMSC PACIFIC-ANTARCTIC RIDGE
NEIC reported an earthquake of M 4.2 in Antigua and Barbuda was not reported felt today.
A strong M 6.0 hit this region last week and this is probably an aftershock
of that event. Today's earthquake occurred while Antigua was at sub-solar
conditions (the sun is directly overhead at local solar noon). This summary
has argued this can lead to enhanced vertical motions in sub-solar latitudes.
Several seismic zones, including central Mexico, Hawaii, Luzon, peninsular
India and the Owen Fracture zone and the Northern Mid-Atlantic (among others)
are current at sub-solar conditions and can expect enhanced seismicity
at this time.
This epicenter is at the ninth node (40 degrees) from Antofagasta and may
have been promoted by energy from that source.
O: 27MAY2026 01:41:38 17.4N 61.2W ML=4.2 EMSC ANTIGUA AND BARBUDA REGION
Other recent examples of sub-solar earthquake include events of M 5.1 and M 4.5 in the northern
Mid-Atlantic Ridge on May 22, 2026; an M 4.2 south of Myanmar on May 22 and the
M 6.0 in Hawaii of May 23, and the M 6.0 in Antigua of May 16, 2026 and a series
of powerful volcanic eruptions in the Central Philippines among others.
O: 16MAY2026 14:50:03 17.5N 61.2W ML=6.0 NEIC ANTIGUA AND BARBUDA
O: 22MAY2026 01:06:53 16.6N 46.7W MW=5.1 EMSC NORTHERN MID-ATLANTIC RIDGE
O: 22MAY2026 23:39:09 17.2N 46.5W MB=4.5 EMSC NORTHERN MID-ATLANTIC RIDGE
O: 22MAY2026 10:26:12 16.4N 96.3E ML=4.2 EMSC NEAR SOUTH COAST OF MYANMAR
O: 23MAY2026 07:46:01 19.4N 155.8W Mw=6.0 EMSC ISLAND OF HAWAII, HAWAII
A series of light earthquakes also occurred west of this in the area of Puerto
Rico and were not reported felt. Puerto Rico is an active zone
NEIC reported an earthquake of M in was felt with intensity up to II-III in the area(s) of
Like Antigua (see above) these epicenters are near a sub-solar latitude
at this time and more enhanced seismicity in the area is likely in the next
week.
O: 27MAY2026 04:27:28 17.8N 68.1W MD=3.2 EMSC DOMINICAN REPUBLIC REGION
O: 26MAY2026 22:10:45 19.4N 69.4W ML=3.3 EMSC DOMINICAN REPUBLIC REGION
O: 27MAY2026 00:32:35 18.9N 65.2W MD=3.1 EMSC PUERTO RICO REGION
O: 27MAY2026 00:18:43 19.0N 65.2W MD=3.0 EMSC PUERTO RICO REGION
O: 27MAY2026 00:23:50 19.0N 65.2W MD=3.5 EMSC PUERTO RICO REGION
O: 27MAY2026 00:28:51 19.0N 65.2W ML=3.5 EMSC PUERTO RICO REGION
The area of San Francisco Bay, California has been relatively quiet in recent
weeks. This summary has followed the sequence of light earthquakes in this
region (mostly because of the peculiar pattern of them occurring very near
local solar midnight and local solar noon with tidal implications). The
area saw three light earthquakes today. These are at the ninth node (80 degrees)
from the Antofagasta epicenter and may have been promoted by energy from
that source or may indicate a re-awakening of the Hayward Fault of San
Andreas in that area.
O: 27MAY2026 01:24:12 37.8N 122.1W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 27MAY2026 02:34:48 37.8N 122.1W MD=2.2 EMSC SAN FRANCISCO BAY AREA, CALIF.
O: 27MAY2026 04:24:40 37.8N 122.1W MD=2.1 EMSC SAN FRANCISCO BAY AREA, CALIF.
EMSC reported an earthquake of M 4.6 in Pakistan was felt with intensity up to IV in the area(s) of Pakistan in Mandi Bahauddin, Kot Mumin, Rawalpindi, Sialkot, Lahore, and in Hisar, India,
This earthquake in Pakistan may have been promoted by solar flare 5290 (C1.6)
as it occurred near the peak output of that flare. A similar event of M 4.5 (not reported felt)
two minutes later in Myanmar may also have been promoted by SFE from that
flare. Data from SWPC for this flare follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
5290 1350 1400 1411 C1.6 (May 26, 2026) 1.9E-03
Pakistan M 4.6 14:05 UT
Myanmar M 4.5 14:07 UT
This epicenter in Pakistan is at 144 degrees from the earthquake in Antofgasta, Chile and may have
been promoted by energy from that source. The event in Myanmar is at the eighth node (45 degrees)
from Honshu, Japan.
O: 26MAY2026 14:05:51 32.6N 73.4E ML=4.6 EMSC PAKISTAN
O: 26MAY2026 14:07:49 23.8N 94.8E ML=4.4 EMSC MYANMAR
EMSC reported an earthquake of M 3.9 in the Caucasus, Russia was felt with intensity up to IV in the area(s) of the Caucasus, Russia at Sochi, Orel-Izumrud, Kudepsta, Vysokoye.
This epicenter is at the fifth node (72 degrees) from Honshu, Japan and may
have been promoted by energy from that source.
O: 26MAY2026 12:08:37 43.4N 39.5E ML=3.9 EMSC CAUCASUS REGION, RUSSIA
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 DEPRESSION JANGMI (06W)
---- ------- ---------- -------- ----- ------ ------- ---------------
TD JANGMI 2026-05-27 00:00 UT 9.6N 137.5E 35 kts North Pacific
TD Jangmi formed today in the north Pacific near the island of Yap with winds up to 35 kts. It is expected to track to the northwest over the next five days reaching the Ryukyu Islands with winds up to 110 kts around May 31 to June 1. This is the first cyclone of the season to threaten the western Pacific subduction zone. First cyclones often trigger significant seismic activity which has built up since the last round of seasonal storms. A moderate to large earthquake in the Central Ryukyu Islands could be anticipated at the end of May or early June as this storm impacts the area. The antipode is currently at 10S 43W, a non-seismic area near the coast of Brazil.
SOLAR FLARES
Following is the listing of C- M- or X-class flares from SWPC for the date
of May 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)
-------------------------------------------------------------------------
5230 0711 0717 0723 C2.4 (May 26, 2026) 1.6E-03
5360 0827 0840 0848 C2.9 (May 26, 2026) 3.4E-03
Vancouver M 2.8 08:27 UT
Java M 4.9 08:39 UT
Guerrero M 4.0 08:50 UT
5270 1230 1238 1244 C9.7 (May 26, 2026) 4.7E-03
5290 1350 1400 1411 C1.6 (May 26, 2026) 1.9E-03
Pakistan M 4.6 14:05 UT
Myanmar M 4.5 14:07 UT
5370 2010 2019 2024 C2.5 (May 26, 2026) 2.0E-03
Honshu, Japan M 4.5 20:21 UT
5380 2040 2048 2051 C1.7 (May 26, 2026) 1.5E-03
5400 2051 2056 2100 C1.8 (May 26, 2026) 1.2E-03
5410 2339 2349 2352 C4.7 (May 26, 2026) 2.2E-03
*indicates modified reading from NOAA GOES Graph
GEOMAGNETIC FIELD: quiet May 29 active May 27-28. Solar M-flare chance: 40% X-class: 5% proton storm: 10%
AP Indicies: global: 8, high: 6, mid-latitude: 7, time of max k: 00:00-03:00 UT; Max k: 3 Global Kp 3.67 2100-2400, May 26; Sunspot Number: 148; Radio Flux: 141
May 26, 2026
Notable earthquakes and events:
Due to the Memorial Day Weekend shutdown (in the U.S. government offices) data from SWPC has been delayed so the following
is largely based on preliminary examination of online graphs and is likely
to be revised as the digital data becomes available.
A strong geomagnetic storm began about 21:50 UT-22:00 UT on May 25, 2026. This involved proton
flux exceeding the SWPC 10 MeV warning threshold with more than 10 particles/flux unit (pfu)
The flux event in protons peaked around 01:10 UT on May 26 with 23.8 pfu. Strong enhancement
of protons were also observed at energy levels of MeV>=50 and MeV>=100. This storm
was reated as a minor S1 Solar Radiation Storm with minor impacts on HF radio through polar regions. Enhanced electron
flux began about 17:00 UT on May 25 (as measured on the GOES-18 Electron flux instrument
and stayed near the alert threshold until about 23:20 UT. The GOES 19 magnetometer
at 72 West longitude recorded a strong decline in global geomagnetic strength
from about 21:30 UT to 22:50 UT indicating the beginning of the proton storm at this longitude. For the day solar radio flux at 10.7 cm
was the highest since May 3-4 and the SESC Sunspot number at 132 was the highest
also once May 3-4, 2026. The proton storm was not reflected in the A or k-indices
for the day. A storm had been expected today as noted in the previous issue of this summary as:
"The M2.3 solar flare (see below and previous issues of this summary) of May 22
has apparently helped to trigger some moderate to large earthquakes (see this
summary and previous ones). NOAA SWPC has issued a geomagnetic storm watch that the earth
is in the path of the CME from this storm. That agency is warning that
this could produce a G2 geomagnetic storm on May 24 into May 26. Areas
which are at local solar noon or local solar midnight are most likely to
see enhanced seismicity when this storm commences. Strong aurora are expected
from Washington to Maine in the U.S. and throughout most of Canada and Alaska
in this time frame." (May 24-25, 2026)
A major earthquake of M 6.9 hit the area of Antofagasta, Chile within minutes of
the commencement of the proton storm (see above). It occurred at an intermediate
depth and was felt widely in Antofagasta, Tarapaca and Atacama, Chile but did
little damage. NEIC reported it was felt with maximum intensity VI in Antofagasta
at Calama and V in Tocopilla with IV in Antofagasta and in Iquique, Tarapaca.
Lesseer shaking of II-II was reported from Taltal, La Serenc, Coquimbo, Diego de Almagro, Copiapo and in Arequipa, Peru.
EMSC reported strong shaking in Chile in Calama, San Pedro de Atacama, Pica, Antofagasta, Iquique, Arica, Copiapo, and in Peru at Ciudad Satelit, Arequipa, and in Londrina, Brazil.
The widespread felt area was likely due to the depth of the earthquake.
An M 4.2 foreshock occurred earlier in the day.
The last earthquake in Antofagasta, Chile with M>=6.9 within about 250 km
of today's epicenter occurred as an M 7.7 on November 14, 2007. Other regional
earthquakes hit on April 3, 2014 near Tarapaca, Chile about 300 km north of today's epicenter
and as an M 7.4 on July 19, 2024 about 250 km southeast of today's epicenter.
At the time of that event this summary noted:
"The strongest earthquake in the world today was an M 7.4 in northern Chile. NEIC reported it was felt with intensity up to VII with
some damage in the Atacama, Chile region near San Pedro de Atacama.
EMSC reported strong and long shaking in Atacama, Chile in San Pedro de Atacama, Calama, Sierra Gorda, Antofagasta, Tocopilla, Mejillones, Alto Hospicio, Iquique, Chanaral, Copiapo, Arica, Paiguano, Arequipa, with light shaking in Coquimbo, Valparaiso, Vina del Mar, Nunoa, Macul and others.
This is the strongest earthquake in the world since an M 7.4 in Taiwan in early
April. The last earthquake within about 300 km of today's epicenter with
M>=7.4 occurred on November 14, 2007 with M 7.7. The only other such event
in the general area of today's epicenter of equal or larger magnitude in the
past 35 years was an M 8.0 on July 30, 1995." (July 19, 2024)
Today's M 6.9 also occurred during the strongest solar flare of the past
two days. This flare of C4.6 (#5140) began about the time of the Chilean earthquake
SFE combined with the Proton Storm (see above) probably helped promote
this earthquake Chile at this time. Several regional aftershocks in Antofagasta
and Tarapaca Chile were also apparently promoted by earlier but smaller
solar flares today. Data on these flares from various sources follow:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4930 0641 0653 0707 C1.7 (May 25, 2026) 2.4E-03 *
Antofagasta M 4.0 07:12 UT
5050 1115 1130 1137 C1.4 (May 25, 2026) 1.2E-03 *
Tarapaca, Chile M 4.2 11:15 UT
Guerrero M 4.0 11:34 UT
Coast northern California M 2.4 11:19 UT
5130 2015 2030 2120 C1.6 (May 25, 2026) 1.5E-03 *
Southern California M 2.5 20:23 UT
Molucca Sea M 5.6 20:39 UT
5140 2030 2230 2359 C4.6 (May 25, 2026) 4.5E-03 *
Antofagasta M 3.0 20:44, M 2.5 20:40 UT
Tarapaca M 3.1 21:37 UT
Antofagasta M 6.9 21:52 UT, M 4.8 22:03 UT M 4.2 22:18 UT
This epicenter is at 147 degrees from the M 7.4 in Honshu, Japan and is
also at the fourth node (90 degrees) from the south Geomagnetic Pole and
may have been promoted by energy from those sources as well.
Surface waves from an M 5.6 in Indonesia 73 minutes earlier would have
been in the area of this earthquake in Chile when it occurred and may
also have helped promote the subsequent earthquake in Chile (see below).
The two strongest aftershocks of the M 6.9 in Antofagasta, Chile today
occurred 11 minutes and 4 seconds after the mainshock (M 4.8) and 16 minutes
later (M 4.2). These match return times of seismic waves reflecting off
the core-mantle boundary (PcP and ScS) at the surface and may have
been promoted by those seismic returns.
O: 25MAY2026 21:52:18 22.5S 68.6W MW=6.9 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 07:12:40 21.5S 70.0W mb=4.0 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 22:08:43 22.2S 68.7W ML=4.2 EMSC ANTOFAGASTA, CHILE
O: 26MAY2026 02:47:00 22.2S 68.9W mb=4.3 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 22:20:44 22.3S 68.7W ML=3.4 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 23:40:27 22.3S 68.7W mb=4.3 EMSC ANTOFAGASTA, CHILE
O: 26MAY2026 00:20:58 22.3S 68.8W mb=4.2 EMSC ANTOFAGASTA, CHILE
O: 26MAY2026 02:26:00 22.3S 68.9W mb=4.2 EMSC ANTOFAGASTA, CHILE
O: 26MAY2026 03:10:59 22.3S 68.7W mb=4.1 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 22:03:22 22.5S 68.9W mb=4.8 EMSC ANTOFAGASTA, CHILE
O: 25MAY2026 21:52:20 22.4S 68.6W MW=6.9 NEIC ANTOFAGASTA, CHILE
O: 25MAY2026 11:15:56 20.6S 69.2W MW=4.2 NEIC TARAPACA, CHILE
O: 25MAY2026 07:53:49 20.8S 69.5W ML=3.5 EMSC TARAPACA, CHILE
O: 25MAY2026 16:20:39 19.8S 69.2W ML=3.2 EMSC TARAPACA, CHILE
O: 25MAY2026 21:37:58 20.0S 69.2W ML=3.1 EMSC TARAPACA, CHILE
O: 25MAY2026 11:15:56 20.7S 69.5W mb=4.2 EMSC TARAPACA, CHILE
NEIC reported an earthquake of M 5.6 in Molucca Sea, Indonesia was felt with intensity up to II-III in the area(s) of Molucca Sea, Indonesia in Bitung.
O: 25MAY2026 20:39:20 1.1N 126.1E MW=5.6 NEIC MOLUCCA SEA, INDONESIA
O: 25MAY2026 17:23:53 2.4N 127.4E ML=4.0 EMSC MOLUCCA SEA
O: 25MAY2026 15:57:30 2.8N 126.4E ML=4.2 EMSC MOLUCCA SEA
O: 25MAY2026 20:39:20 1.1N 126.1E MW=5.6 EMSC MOLUCCA SEA
NEIC reported an earthquake of M 3.4 in Northern California was felt with intensity up to II-III in the area(s) of Northern California in Old Station, Chico, Downieville, Red Bluff and Oakland.
O: 26MAY2026 05:11:52 40.7N 121.5W ML=3.2 EMSC NORTHERN CALIFORNIA
O: 26MAY2026 05:11:52 40.7N 121.4W MB=3.4 NEIC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.2 in Malibu Beach, Southern California was felt with intensity up to II-III in the area(s) of Maliby Beach, Southern California was widely felt in Reseda, Santa Monica, Calabasas, Malibu, Agoura Hills, Newport Beach, Canoga Park, and Woodland Hills.
O: 26MAY2026 03:11:58 34.0N 118.7W MB=3.2 NEIC SOUTHERN CALIFORNIA
O: 25MAY2026 20:23:15 33.9N 119.5W ML=2.5 EMSC CHANNEL ISLANDS REG., CALIFORN
O: 26MAY2026 03:11:57 34.0N 118.7W ML=3.0 EMSC SANTA MONICA BAY, CALIFORNIA
EMSC reported an earthquake of M 4.5 in Eastern Kazakhstan was felt with intensity up to IV in the area(s) of Eastern Kazakhstan in Ekibastuz.
O: 26MAY2026 06:27:44 51.6N 75.4E MB=4.5 EMSC EASTERN KAZAKHSTAN
EMSC reported an earthquake of M 4.8 in Kamchatka was felt with intensity up to IV in the area(s) of Kamchatka in Paratunka.
O: 25MAY2026 23:31:46 53.3N 159.7E MB=4.8 EMSC NEAR EAST COAST OF KAMCHATKA
EMSC reported an earthquake of M 4.1 in Central Turkey was felt with intensity up to IV in the area(s) of Central Turkey in Kadrili, Goksun, Kaharmanmaras, Nigde, Sahinbey, and Karatas.
O: 25MAY2026 18:44:54 37.7N 36.1E MB=4.1 EMSC CENTRAL TURKEY
EMSC reported an earthquake of M 4.0 in southern Greece was felt with intensity up to IV in the area(s) of Southern Greece at Varda, Lechaina, Nea Manolada, Pyrgos, Kardamas, Katakolo, Dato Achaia, Kaminia, Kestena, Parala, Patra, Laganas, Zante.
O: 25MAY2026 18:50:01 37.9N 21.4E MB=4.0 EMSC SOUTHERN 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 May 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 1215 1230 1300 C9.7 (May 26, 2026) 9.5E-03 *
4900 0051 0104 0115 C3.7 (May 25, 2026) 3.5E-03 *
Guatemala M 4.4, M 4.4 00:54, 00:55 UT
4930 0641 0653 0707 C1.7 (May 25, 2026) 2.4E-03 *
Antofagasta M 4.0 07:12 UT
5050 1115 1130 1137 C1.4 (May 25, 2026) 1.2E-03 *
Tarapaca, Chile M 4.2 11:15 UT
Guerrero M 4.0 11:34 UT
Coast northern California M 2.4 11:19 UT
5130 2015 2030 2120 C1.6 (May 25, 2026) 1.5E-03 *
Southern California M 2.5 20:23 UT
Molucca Sea M 5.6 20:39 UT
5140 2030 2230 2359 C4.6 (May 25, 2026) 4.5E-03
Antofagasta M 3.0 20:44, M 2.5 20:40 UT
Tarapaca M 3.1 21:37 UT
Antofagasta M 6.9 21:52 UT, M 4.8 22:03 UT M 4.2 22:18 UT
Papua, Indonesia M 4.9 22:03.
GEOMAGNETIC FIELD: unsettled May 26 active May 27-28. Solar M-flare chance: 35% X-class: 5% proton storm: 5%
AP Indicies: global: 8, high: 10, mid-latitude: 8, time of max k: 13:00-18:00 UT; Max k: 3 Global Kp 2.67 2100-2400, May 25; Sunspot Number: 132; Radio Flux: 139
May 25, 2026
Notable earthquakes and events:
A geomagnetic excursion in the strength of the geomagnetic field of the earth
at satellite altitudes occurred beginning around 03:40 UT on May 25. It reached
its peak at about 05:10 UT (on GOES 18 magnetometer). An arcjet correction
to the orbit was required at that time and normal operations continued
at about 06:10 UT. This may have been part of a broader storm which may have
begun around 01:30 UT but this cannot be confirmed from Kp data at this time.
Electron flux dropped from storm levels to quiet near this time however.
There were no changes in proton flux levels.
At the time of the excursion two moderate earthquakes were recorded at high latitude.
The first of these was an M 4.8 in the Fox Islands, part of the continuing series in that
area at 05:18 UT and the second occurred in the Jan Mayen Island area of the
Arctic with M 4.5 at 05:21 UT. It was fikkiwed by an M 4.0 in the Rat Islands,
Aleutians minutes later. None of these events were reported felt.
O: 25MAY2026 05:18:12 51.9N 170.9W ML=4.9 NEIC FOX ISLANDS, ALEUTIAN ISLANDS
O: 25MAY2026 05:21:14 71.5N 3.4W ML=4.5 NEIC JAN MAYEN ISLANDS REGION
O: 25MAY2026 05:28:14 51.0N 179.3E ML=4.0 NEIC RAT ISLANDS, ALEUTIAN ISLANDS
The strongest earthquake in the world today was an M 5.5 in northern Mindanao, Philippines.
NEIC reported it was felt with intensity V in Caraga, Philippines at Dapa and IV in Purok and III in Butuan. It was also felt in Mindanao and the Eastern Visayas and Samar at San Antonio, Davao and Malandag with II-III intensity.
EMSC reported moderate shaking in the Philippines in Tandag, Hinatuan, Danao. An earthquake alert was available on mobile phones for this event.
This earthquake occurred within minutes of local solar midnight and may have
been promoted by tidal and/or geomagnetic effects which maximize near this hour.
The last earthquake in northern Mindanao within about 200 km of today's epicenter
with equal or greater magnitude than M 5.5 occurred as an M 6.1 on October 16, 2025.
At the time this summary noted:
"Aftershocks also continued today in the region of northern Mindanao, Philippines.
These occurred with maximum M 6.1 on the Philippines Trench. NEIC reported it was felt with intensity V in Caraga at Luna, IV in Purok, Tago, Calero, Central Sisayas and Nabunturan, Mindanao with III in Brasilisa, Davao, Libertad, Los Angeles, Butuan and II in Mandawa, Barra, Tangnan and Ula.
EMSC reported moderate to strong shaking in General Luna, Libas, Calver, Placer, Dinagat, Mati, Jabonga, Cabadbaran, Low Angeles, Libertad, Hinunangan, Butuan City, Southern Leyte, Bah-Bah, La Paz, Gabas, Cagayan de Oro, Igpit among others.
PHIVOLCS reported intensity V i General Luna, Claver, Pilar, Placer, San Benito, San Isidro and Socorro, Surigao del Norte; Basilisa, Cagdianao, Dinagat and San Jose, Denagat Islands; IV in the City of Butuan, Surigao del Norte, Dinagat Islands, southern Leyte, Surigao del Sur and Agusan del Sur with shaking or II-III throughout the general region.
The earthquake of M 6.1 in Mindanao is the strongest within about 200 km
of this epicenter since an M 6.5 on February 10, 2017 and fills a gap in the stress release
along the Philippines Trench. At the time this summary noted:
"A strong earthquake of M 6.5 hit the region of northern Mindanao, Philippines today.
NEIC reported it was felt with maximum intensity VII in Buenavista, Caraga, Philippines and V in Manila de Bugabus, Butuan, Union; IV in the Visayas at Leyte, San Francisco, Purok, Tabontabon, Pawing, Tangke. Intensity II-III was reported as far as 300 km from the epicenter at Davao, Southern Mindanao, Panabo, Tagum, Dumaguete, Sumpong, Hinatuan, Lumbia, Baikingon, Cagayan, Barra, Calero, Cebu, Mandawa, Bugo, Lapu-Lapu, Tagoloan, Balilihan, San Antonio, Ormoc, Balingasag, Baras, Bayugan, Talisayan, San Miguel, Abuyog, Madrid, Carrascal, Sogod, Macrohon and Tubajon, Philippines.
PHIVOLCS reported it was felt with intensity VII in Surigao City; VI in Malimono and San Francisco, Surigao Del Nothe; Pintuyan Southern Leyte; V in Mainit and Placer, Surigao Del Norte; Libjo and San Joses, Dinagat Island; Mandaue City; San Ricardo, Limasawa and San Francisco, Southern Leyte; IV in Hinunangan and San Juan, Southern Leyte; Abuyog, Leyte, Mayorga, Leyte; Butuan Cith; Cabadaran, Agusan del North; III in Mambajao,k Caminguin, Oormac City; Palo, Pastana, Tolosa and Tacloban, Leyte; Catbalogan City, W. Samar; Bislig City, Gingoon City, Misamis Oriental; Adpa, Surigao Del Norte, Iligan City; Cagayan De Oro City and II in Cebu City; Talocogon, Agusan del Sur; Dumaguete City; Tagbilaran City, Bohol, Capoocan, Leyte; El Salvador, Misamis Oriental; Oroquieta City and Blaridel Misamis Occidental, Philippines.
The last earthquake of M>=6.5 within about 250 km of this epicenter was widely
felt on October 15, 2013 with M 7.1 in the Bohol area and did extensive
damage and loss of life in the area. An earthquake of M 7.6 hit about 150
km northeast of today's epicenter on August 31 2012." (October 16, 2025)
This epicenter is at the fifth node (72 degrees) from the South Geomagnetic
Pole and may have been promoted by energy from that source.
O: 24MAY2026 16:48:40 9.3N 126.3E ML=5.5 NEIC MINDANAO, PHILIPPINES
O: 24MAY2026 16:48:42 9.3N 126.3E MW=5.5 EMSC MINDANAO, PHILIPPINES
O: 24MAY2026 13:19:06 9.2N 126.5E mb=5.0 EMSC MINDANAO, PHILIPPINES
O: 24MAY2026 13:19:06 9.1N 126.5E ML=5.0 NEIC MINDANAO, PHILIPPINES
O: 25MAY2026 02:32:38 8.0N 126.9E MB=5.0 EMSC MINDANAO, PHILIPPINES
NEIC reported an earthquake of M 4.1 in Western Nevada was felt with intensity up to II-III in the area(s) of Nevada near Mina and possibly in Las Vegas.
While minor earthquakes are common in this area, earthquakes of M>=4.1
are relative rare. An M 4.5 hit about 100 km south of this in Nevada on June 29, 2025
but the last event within 100 km of M>=4.1 was an M 4.3 on November 14, 2024.
At that time this summary noted:
"The strongest earthquake in the U.S. or Canada outside Alaska today was an M 4.3 in Nevada. NEIC reported it was felt with intensity IV in Nevada at Silverpeak and Luning and II in Tonopah, Fallon and Gardnerville.
The last earthquake within about 100 km of this event in Nevada with M>=4.3
was recorded by NEIC on November 10, 2023 (one year ago) with M 4.3. At the
time this summary noted:
"The strongest earthquake felt in the U.S. or Canada today was an 4.3 in western Nevada. It was reported by NEIC to have been lightly felt in the area of Mina, Nevada.
The last earthquake within about 50 km of today's M 4.3 was an M 4.7 on February 15, 2022.
These are aftershocks of an M 6.5 which occurred on May 15, 2020." (November 10, 2023, November 14, 2024)
Today's event in Nevada occurred near local solar midnight and may have been promoted tidal
and/or geomagnetic effects which maximize near this hour.
This epicenter is at the seventh node (51.4 degrees) from the North Geomagnetic
Pole and the fifth node (72 degrees) from Honshu, Japan and may have
been promoted by energy from those sources.
O: 25MAY2026 08:52:42 38.2N 117.9W ML=4.1 NEIC WESTERN NEVADA
NEIC reported an earthquake of M 4.8 in the Fox Islands, Alaska was felt with intensity up to II-III in the area(s) of the Fox Islands, Alaska
This continues a series which has been ongoing for several days in the Fox Islands.
This earthquake occurred at the beginning of a satellite altitude geomagnetic
excursion (see above) and may have been promoted by that geomagnetic variation
in the earth's field.
This series is near the fifth node (72 degrees) from Tonga, Malaysia, Vanuatu, Molucca Sea
and may have been promoted by constructive interference of energy from those sources.
O: 25MAY2026 05:18:12 52.0N 170.9W ML=4.8 NEIC FOX ISLANDS, ALASKA
O: 24MAY2026 09:45:22 51.8N 170.4W MB=4.5 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
NEIC reported an earthquake of M 4.1 in Coquimbo, Chile was felt with intensity up to II-III in the area(s) of Coquimbo, Chile in La Serena.
EMSC reported light shaking in Coquimbo, Chile.
O: 24MAY2026 23:25:17 30.6S 71.7W ML=4.1 NEIC COQUIMBO, CHILE
O: 24MAY2026 23:25:16 30.6S 71.7W MW=4.2 EMSC COQUIMBO, CHILE
NEIC reported an earthquake of M 3.4 in Southeastern Alaska was felt with intensity up to II-III in the area(s) of Southeastern Alaska at Haines.
This epicenter is at the seventh node (52 degrees) from Honshu, Japan
and may have been promoted by energy from that source.
O: 24MAY2026 12:23:40 59.1N 136.3W ML=3.4 NEIC SOUTHEASTERN ALASKA
O: 24MAY2026 12:23:40 59.2N 136.4W ML=3.4 EMSC SOUTHEASTERN ALASKA
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 in Colakli, Malatya, Battalgazi, Yesilyurt, Elazig and Harput.
O: 24MAY2026 19:36:49 38.2N 38.6E ML=4.0 NEIC EASTERN TURKEY
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 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)
-------------------------------------------------------------------------
4710 0048 0104 0108 C3.5 (May 24, 2026) 2.8E-03
Venezuela M 4.3 00:58 UT
Central Turkey M 4.9 01:27 UT
4740 0218 0225 0230 C3.4 (May 24, 2026) 2.4E-03
4750 0233 0237 0240 C3.7 (May 24, 2026) 1.7E-03
4860 1828 1837 1845 C1.2 (May 24, 2026) 1.2E-03
Iceland M 3.0 18:31 UT
GEOMAGNETIC FIELD: quiet May 25 unsettled May 26-27. Solar M-flare chance: 35% X-class: 5% proton storm: 5%
AP Indicies: global: 6, high: 3, mid-latitude: 7, time of max k: 15:00-18:00 UT; Max k: 3 Global Kp 2.00 2000-2400, May 24; Sunspot Number: 86; Radio Flux: 133
May 24, 2026
Notable earthquakes and events:
The M2.3 solar flare (see below and previous issues of this summary) of May 22
has apparently helped to trigger some moderate to large earthquakes (see this
summary and previous ones). NOAA SWPC has issued a geomagnetic storm watch that the earth
is in the path of the CME from this storm. That agency is warning that
this could produce a G2 geomagnetic storm on May 24 into May 26. Areas
which are at local solar noon or local solar midnight are most likely to
see enhanced seismicity when this storm commences. Strong aurora are expected
from Washington to Maine in the U.S. and throughout most of Canada and Alaska
in this time frame.
The strongest earthquake in the U.S. or Canada since last report was an M 5.3 in the Fox Islands, Alaska.
NEIC reported it may have been lightly felt in the area of Nikolski, Alaska.
A foreshock of M 4.9 occurred earlier in the day and may also have been felt in the area of Nikolski.
This earthquake occurred near local solar noon and may have been promoted
by tidal and/or geomagnetic effects which maximize near this hour.
This epicenter is near the fifth node (72 degrees) from Tonga, Malaysia, Vanuatu and
the Molucca Sea and at the 10th node (36 degrees) from the North Geomagnetic
Pole and could have been promoted by energy from those sources.
O: 23MAY2026 16:28:16 51.8N 170.4W ML=3.9 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 23MAY2026 21:49:17 51.8N 170.5W Mw=5.3 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 23MAY2026 09:03:09 52.3N 169.4W mb=4.9 EMSC FOX ISLANDS, ALEUTIAN ISLANDS
O: 23MAY2026 21:49:16 51.7N 170.3W ML=5.3 NEIC FOX ISLANDS, ALASKA
NEIC reported an earthquake of M 4.6 in Central Chile was felt with intensity up to II-III in the area(s) of Central Chile in Los Lagos at Valdivia.
This epicenter is at the fifth node (72 degrees) from the South Geomagnetic Pole and at
101 degrees from Vanuatu and may have been promoted by energy from those sources.
O: 24MAY2026 04:14:55 39.6S 74.1W ML=4.6 NEIC LOS LAGOS, CHILE
O: 24MAY2026 04:14:55 39.6S 74.1W MB=4.6 EMSC OFFSHORE LOS LAGOS, CHILE
NEIC reported an earthquake of M 4.9 in Samoa was not reported felt in this remote
area but may have been felt with light intensity in Gataivai, Samoa. This earthquake occurred within minutes of local solar noon and may
have been promoted by tidal and/or geomagnetic effects which maximize near this hour.
This epicenter is located on the geomagnetic equator and is 102 degrees from the
North Geomagnetic Pole and at the sixth node (60 degrees) from the South
Geomagnetic pole and may have been promoted by geomagnetic energy associated
with the recent geomagnetic storms concentrated near those points.
O: 23MAY2026 23:54:28 14.9S 173.0W ML=4.9 NEIC SAMOA
O: 23MAY2026 23:54:28 14.9S 173.0W MB=4.9 EMSC SAMOA ISLANDS
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 in Juneau.
O: 23MAY2026 14:29:36 60.6N 140.0W ML=3.8 NEIC SOUTHEASTERN ALASKA
O: 23MAY2026 14:29:37 60.5N 140.0W ML=3.7 EMSC SOUTHERN YUKON TERRITORY, CANA
NEIC reported an earthquake of M 4.6 in Crete, Greece was felt with intensity up to II-III in the area(s) of Crete in Fry, Greece.
EMSC reported moderate shaking in Karpathos and Sitia, Greece.
This epicenter was near local solar midnight when this earthquake occurred
and may have been promoted by tidal and/or geomagnetic stresses.
O: 23MAY2026 13:34:13 34.5N 26.5E ML=4.6 NEIC CRETE, GREECE
O: 23MAY2026 14:40:57 35.4N 26.6E ML=4.0 EMSC CRETE, GREECE
O: 23MAY2026 13:34:13 35.4N 26.6E ML=4.4 EMSC CRETE, GREECE
A strong M 6.0 earthquake also occurred at the longitude at local solar
midnight when this solar flare occurred. A fluctuation in the GOES-18 magnetometer at 137 West longitude
which began at about 21:29 UT and finished at 22:47 UT on May 22, 2026
occurred when this longitude and latitude in Hawaii were very close to
exact sub-solar conditions and may have been promoted by that geomagnetic event.The event at 155 West longitude was widely
felt in Hawaii and occurred near the largest volcano on planet Earth - Launa Loa.
It could help initiate enhanced seismicity and volcanism in the Island of
Hawaii. NEIC received more than 6000 felt reports from citizens regarding the effects of this quake.
These include intensities VII in Hawaii at Captain Cook; VI in Kealakekua, Naalehu, Holualoa ; V in Pahala, Kailua Kona, Ookala, Honokaa, Hawaii National Park, Hakalau and IV in Kapaau, Honomu, Kamuela, Waikoloa, Pepeekeo, Laupahoehoe, Paauilo, Papaikou, Hawi, Mountain View, Volcano, Papaaloa, Pahoa, Kula, Fort Shafter, Hilo, Nonole, Kurtistown, Keaau, Wailuku, Paia, Kihei, with lesser shaking throughout much of the remaining Hawaiian Islands. EMSC reported the mainshock was strongly felt with long duration in
Hawaii at Kailua-Kona, Hawaiian Ocean View, Kalaoa, Naalehu, Volcano, Fern Forest, Honoka'a, Papaiikou, Pepeeleo, Ainaloa, Hawaiian Paradise Park, Kihei, Haiku-Pauwela, Kahului, Kaanapali Landing, Napili-Honokowai, East Honolulu, Honolulu, Kaneohe, Village Prk, Waipi'o Acres, Waianae, Lawai.
The last earthquake in the area of Hawaii of M>=6 occurred on October 10, 2021
with M 6.2. The strongest in the past 35 years were an M 6.9 on May 4, 2018 and an M 6.7
on October 15, 2006. At the time of the M 6.9 on May 4, 2018 this summary noted:
One of the strongest solar flares today was nearing the end of its X-ray output
when the earthquake in Hawaii occurred. SFE from this flare may have helped
promoted the Hawaiian event. Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4520 0711 0717 0745 C2.1 (May 23, 2026) 1.3E-03 *
Guerrero M 4.0 07:09 UT
Hawaii M 6.0 07:46 UT
"A major earthquake of M 6.9-7.0 hit the island of Hawaii today after several days
of increasing seismicity and volcanism in the area. This included the strongest
quake of the series which occurred about an hour prior to the mainshock with M 5.4. NEIC reported damage with
this earthquake but no major tsunami was observed. The earthquake occurred
within about 15 minutes of local solar noon and was probably promoted by tidal
stresses which maximize at this hour.
NEIC reported the mainshock was felt throughout the area of Hawaii. Intensity VI-VII was
felt within about 100 km of the epicenter at Pahoa, Mountain View, Kurtistown, Volcano, Keaau, Hawaii National Park, Hilo, Papaikou, Pepeekeo, Pahala, with lesser shaking within about 500 km of the epicenter.
An M 5.3 followed about 40 km north of the epicenter of the major quake. NEIC reported it was felt with intensity IV in Hilo and II-III in Volcano, Pahoa, Naalehu, Mountain View, Kurtistown, Captain Cook, Keaau, Papaiko, Paauilo and within about 100 km of the epicenter. The strongest aftershock were of M 4.6-5.0. They were generally reported felt with intensity II-III in Pahoa, Keaau, Papaikou, Hilo, Pepeekeo, Kamuela and Kihei, Hawaii.: (May 4, 2018)
This epicenter is near the sub-solar latitude (near 17-18 North on May 23).
This summary has argued in previous issues that vertical tidal stresses
which are maximized near sub-solar conditions (sun directly overhead at
local solar noon) can help promote stronger seismicity than normal on
those days and time, and this appears to be the case in this situation
in Hawaii.
Spectacular fountains of lava and eruptive material also continued in
the area of Kilauea east of today's epicenter in an ongoing eruption
at that volcano in Hawaii.
This earthquake was discussed upon in the last issue of this summary.
Aftershocks have been lightly felt with M 3.2 in western Hawaii at Captain Cook.
The strongest aftershock at this writing was an M 4.0. NEIC reported it was felt
with intensity IV in western Hawaii at Captain Cook; III in Kihei, Naalehu, Kailua Kona and II in Holualoa, Kamuela, Lahaina, Pahoa and Honolulu.
O: 23MAY2026 07:46:01 19.4N 155.8W ML=6.0 NEIC ISLAND OF HAWAII
O: 23MAY2026 17:25:12 19.6N 155.9W ML=3.2 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 10:56:07 19.3N 155.9W mb=4.0 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 13:01:27 19.3N 155.4W ML=3.2 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 07:46:01 19.4N 155.8W Mw=6.0 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 07:52:27 19.4N 155.8W ML=3.4 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 12:41:00 19.4N 155.9W MD=3.2 EMSC ISLAND OF HAWAII, HAWAII
O: 23MAY2026 12:41:02 19.4N 155.9W ML=3.2 NEIC ISLAND OF HAWAII
O: 23MAY2026 10:56:07 19.3N 155.9W ML=4.0 NEIC ISLAND OF HAWAII
NEIC reported an earthquake of M 5.2 in Southern Sumatra was felt with intensity up to II-III in the area(s) of Southern Sumatra in Lubuk Linggau, Sumatra.
O: 23MAY2026 12:40:25 4.7S 102.6E ML=5.2 NEIC SOUTHERN SUMATRA, INDONESIA
O: 23MAY2026 12:40:26 4.6S 102.6E MB=5.2 EMSC SOUTHERN SUMATRA, INDONESIA
O: 23MAY2026 18:08:19 5.3S 102.5E ML=4.1 EMSC SOUTHERN SUMATRA, INDONESIA
NEIC reported an earthquake of M 4.5 in Ecuador may have been felt near Sucia, Ecuador.
O: 23MAY2026 08:44:52 2.6S 77.5W ML=4.5 NEIC ECUADOR
O: 23MAY2026 08:44:50 2.6S 77.5W MB=4.5 EMSC PERU-ECUADOR BORDER REGION
NEIC reported an earthquake of M 4.9 in Turkey was felt with intensity up to IV in the area(s) of Turkey in Develi, Kayseri.
EMSC reported moderate shaking in Turkey at Andirin, Goksun, Kozan, Kadirli, Yenicekale, Kahranammaras, Bahce, Yuregir, Elbistan, Seyhan, Adana, Talas, Kocasinan, Kayseri Sahinbey, Sehitkamil, Gaziantep, Yesildere, and in Syria at I'zaz and Aleppo.
This earthquake near the Turkey-Syria border is the strongest within about
200 km of today's epicenter since an M 5.0 on September 9, 2024. Today's event
is the probably a regional aftershock of a great
earthquake of M 7.8 which hit about 100 km east of this epicenter on February 6, 2023.
At the time this summary noted:
"Two major to great earthquakes occurred today in Central and eastern Turkey. The first of these was an M 7.8
but an M 7.5 occurred within minutes of local solar noon later in the day and
was probably triggered by high tidal stresses which maximize near this hour.
Press reports indicate it was felt from Eastern Turkey to the Mediterranean Sea and Cairo, Egypt.
At least 1500 are confirmed dead and many more have probably perished in this earthquake of M 7.7-7.9.
Many buildings were destroyed or damaged. This is an area where large number
of refugees are stationed. These people have fled regional conflicts in Syria,
Iran and Ukraine in recent years. Many of these camps were damaged in these
earthquakes. At this writing official tolls include 1014 dead, 5383 injured, 29818 building collapsed in Turkey and 326 killed, 1042 injured in Syria.
Widespread damage occurred for several hundred km running Southwest to Northeast. The mainshock epicenter was near Gaziantep where
a thousand's year historic castlw was also damage. NEIC reported intensity IV in Hasanbeyli, Osmaniey and Islahiye, Gaziantep with VIII also in Nizip and VII in Ikenderun, Turkey and Aleppo, Syria. The mainshock was felt with intensity IV-VI as far as Cairo, Egype, Kuwait, Tebriz, Iran, Izmir, Turkey, Iraq, Israel, Palestine, Georgia, Jordan, Cyprus, Lebanon. Many moderate aftershocks followed and were felt with moderate to light intensity in the epicentral area.
An M 7.7 occurred later northeast of Kahramanmaras, Turkey. Pictures on the internet
show massive destruction throughout the area. Rescue teams from
many countries are flooding the area. A tsunami warning was issued for areas of the
Mediterranean and Black Sea but was later withdrawn. The strongest immediate aftershock was an M 6.7 which was felt with intensity VII inTurkey at Urfa, and Syria at Latakia; VI wsa reported in Adana, Turkey and Tartus, Syria; V in Gaziantep, Erdemli, Turkey and in Hims, Syria and in Lebanon among other areas.
This may have been triggered by the onset of a strong geomagnetic storm. This storm began
with an arcjet at 00:00 UT on February 6, 2023 and ended after the geomagnetic
field at satellite altitudes had dropped from about 100 Nanoteslas (nT) to about 40
NT when it ended abruptly at 01:16 UT (GOES 16 Hp via NOAA). The earthquake in
Turkey occurred at 01:17 UT and was likely triggered by this major change
in the intensity of the geomagnetic field.
The mainshock also occurred within several hours of the complete full moon" (February 6, 2023)
Today's epicenter was nearly at local solar noon when the M2.3 solar flare
occurred on May 22. When that occurred this summary anticipated enhanced
seismicity in this area (and Crete, Greece - see above) in the short
period following as:
"A strong M2.3 solar flare (#4410) occurred on May 22, 2026 with maximum
output (as per SWPC data) at 10:29 UT. This is the strongest solar flare
reported by SWPC since an M5.7 (#2450) on May 10, 2026, two weeks ago.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4410 1003 1029 1101 M2.3 (May 22, 2026) 5.3E-02
Admiralty Islands M 5.7 10:08 UT
Sudden strong solar flares can help to trigger volcanism and seismicity in areas
which are near local solar noon or local solar midnight at the time of
their occurrence or concurrent with the flare. The peak of this flare
occurred at 10:29 UT. Areas at local solar noon at this hour are in Central
Europe near 22 East longitude .." (May 22-24, 2026)
This epicenter is at the fourth node (90 degrees) from the Molucca Sea
and may have been promoted by energy from that sources.
O: 24MAY2026 01:26:53 37.8N 36.1E ML=4.9 NEIC CENTRAL TURKEY
O: 24MAY2026 01:26:53 37.8N 36.1E MW=4.9 EMSC CENTRAL TURKEY
NEIC reported an earthquake of M 4.6 in North Island, New Zealand was felt with intensity up to IV in the area(s) of North Island, New Zealand near Hicks Bay.
GeoNet gives the following data for this earthquake.
O: 23MAY2026 15:25:40 37.9S 179.1E ML=4.3 GEONET 2 people reported feeling this earthquake with 1 at weak intensity and 1 with light shaking and 0 with moderate intensity 0 with strong, 0 with severe and 0 with extreme intensity.
O: 23MAY2026 15:25:37 38.1S 179.3E MB=4.6 EMSC OFF E. COAST OF N. ISLAND, N.Z
O: 23MAY2026 15:25:37 38.1S 179.4E ML=4.6 NEIC NORTH ISLAND, NEW ZEALAND
EMSC reported an earthquake of M 4.5 in the Kuril Islands was felt with intensity up to IV in the area(s) of the Kuril Islands in Shikotan, Russia.
O: 24MAY2026 06:51:34 43.1N 146.5E ML=4.5 NEIC KURIL ISLANDS
O: 24MAY2026 06:51:34 43.2N 146.5E MB=4.5 EMSC KURIL ISLANDS
NEIC reported an earthquake of M 5.7 in the Southeast Indian Ridge was not felt in this remote area of the Southeast Indian Ridge.
This is the strongest earthquake in the Southeast Indian Ridge since an
M 6.6 on April 16, 2025. At the time this summary noted:
"The strongest earthquake of the day was an M 6.6 in the southeast Indian Ridge southwest of Australia.
It was not reported felt in this remote area and like most strong earthquakes
on Ocean Ridges was not expected to produce a notable tsunami and no tsunami
waves were reported. It was followed by an M 5.2 aftershock 43 minutes later.
This event is the strongest earthquake within about 300 km of this epicenter
on the Southeast Indian Ridge since an M 6.6 on June 13, 2002, the only such
event in this region in the past 35 years. At the time this summary noted:
"A strong earthquake occurred in the southeast Indian Ridge this
morning. This event has initial Ms 6.5 (NEIS). This is one of the
largest events ever recorded in this section of the SE Indian
Ridge" (June 13, 2002)
This epicenter in the Indian Ridge - at 99E longitude - was at local solar midnight
when the geomagnetic storm began at 17:10 UT and was likely promoted by geomagnetic effects." (April 16, 2025)
This epicenter is at the seventh node (53 degrees) from the Molucca Sea
and may have been promoted by energy from that source.
This earthquake occurred within a couple of minutes of local solar noon
and was likely promoted by tidal and/or geomagnetic effects which maximize
near this hour. The second strongest solar flare of the day (#4510 C3.6)
reached its maximum output when this earthquake occurred. It is likely
SFE from this flare helped trigger this noon time earthquake in the Indian
Ridge. Data from SWPC for this flare follow.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4510 0535 0548 0553 C3.6 (May 23, 2026) 2.4E-03
Southeast Indian Ridge M 5.6 05:41 UT
O: 23MAY2026 05:41:34 47.5D 100.0E ML=5.7 NEIC SOUTHEAST INDIAN RIDGE
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 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)
-------------------------------------------------------------------------
4480 0217 0224 0229 C1.6 (May 23, 2026) 1.1E-03
4490 0322 0327 0332 C1.3 (May 23, 2026) 8.0E-04
4500 0346 0350 0353 C1.4 (May 23, 2026) 5.7E-04
Guerrero M 4.1 03:45 UT
4510 0535 0548 0553 C3.6 (May 23, 2026) 2.4E-03
Southeast Indian Ridge M 5.6 05:41 UT
4520 0711 0717 0745 C2.1 (May 23, 2026) 1.3E-03 *
Guerrero M 4.0 07:09 UT
Hawaii M 6.0 07:46 UT
4530 0910 0913 0916 C1.9 (May 23, 2026) 6.9E-04
4550 1135 1144 1147 C2.9 (May 23, 2026) 1.3E-03
Sumatra M 5.2 12:40 UT
4570 1402 1411 1415 C2.3 (May 23, 2026) 1.4E-03
Halmahera M 4.8 14:11 UT
4590 1647 1656 1704 C1.6 (May 23, 2026) 1.7E-03
4600 1708 1714 1719 C1.8 (May 23, 2026) 1.3E-03
Lombok, Indonesia M 4.1 17:12 UT
4610 1734 1746 1755 C2.0 (May 23, 2026) 2.4E-03
Fiji M 4.4 17:39 UT
4640 1907 1932 1945 C2.7 (May 23, 2026) 6.3E-03
4640 1945 1955 2002 C2.8 (May 23, 2026) 3.2E-03
Sumatra M 3.1 19:45 UT
Cook Strait M 3.5 19:45 UT
Molucca Sea M 4.0 19:49 UT
4660 2100 2105 2112 C2.9 (May 23, 2026) 2.1E-03
4670 2157 2204 2207 C5.5 (May 23, 2026) 2.3E-03
Honshu M 4.0 22:06 UT
Antofagasta M 4.3 22:15 UT
4680 2223 2232 2253 C2.5 (May 23, 2026) 4.2E-03
Southern Greece M 3.9 22:30 UT
Fiji M 4.0 22:51 UT
Iceland M 2.8 22:44 UT
GEOMAGNETIC FIELD: quiet May 24-25 unsettled May 26. Solar M-flare chance: 35% X-class: 5% proton storm: 5%
AP Indicies: global: 3, high: 2, mid-latitude: 4, time of max k: 15:00-22:00 UT; Max k: 2 Global Kp 1.33 0600-0900, May 23; Sunspot Number: 86; Radio Flux: 137
May 23, 2026
Notable earthquakes and events:
A strong M2.3 solar flare (#4410) occurred on May 22, 2026 with maximum
output (as per SWPC data) at 10:29 UT. This is the strongest solar flare
reported by SWPC since an M5.7 (#2450) on May 10, 2026, two weeks ago.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4410 1003 1029 1101 M2.3 (May 22, 2026) 5.3E-02
Admiralty Islands M 5.7 10:08 UT
Sudden strong solar flares can help to trigger volcanism and seismicity in areas
which are near local solar noon or local solar midnight at the time of
their occurrence or concurrent with the flare. The peak of this flare
occurred at 10:29 UT. Areas at local solar noon at this hour are in Central
Europe near 22 East longitude while areas at local solar midnight
are near 156 West longitude and include Alaska and Hawaii. In the current circumstances
an M 5.7 earthquake in the Admiralty Islands of Papua New Guinea
occurred at 10:03 UT at the start of this flare. This is part of an
ongoing submarine volcanic eruption which began in early May, 2026 in the Admiralty Islands.
This summary has been following this eruption for example as:
"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." (May 8, 2026)
"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." (May 9, 2026)
A M 5.1 earthquake on May 17, 2026 was also closely associated with
a solar flare and was discussed in this summary at the time as:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3770 0745 0757 0809 B9.0 (May 17, 2026) 1.2E-03
Admiralty Is. M 5.1 07:52 UT
A strong excursion in the geomagnetic field was also reported from the GOES 18 satellite
as beginning within a minute of 10:08 UT today. This was simultaneous with
the M 5.7 in the Admiralty Islands today.
O: 22MAY2026 10:08:23 2.9S 147.7E ML=5.7 EMSC ADMIRALTY ISLANDS, PAPUA NEW GUINEA
O: 22MAY2026 10:08:19 2.9S 147.7E ML=5.7 NEIC ADMIRALTY ISLANDS, PAPUA NEW GUINEA
A strong M 6.0 earthquake also occurred at the longitude at local solar
midnight when this solar flare occurred. A fluctuation in the GOES-18 magnetometer at 137 West longitude
which began at about 21:29 UT and finished at 22:47 UT on May 22, 2026
occurred when this longitude and latitude in Hawaii were very close to
exact sub-solar conditions and may have been promoted by that geomagnetic event.The event at 155 West longitude was widely
felt in Hawaii and occurred near the largest volcano on planet Earth - Launa Loa.
It could help initiate enhanced seismicity and volcanism in the Island of
Hawaii. NEIC received more than 6000 felt reports from citizens regarding the effects of this quake.
These include intensities VII in Hawaii at Captain Cook; VI in Kealakekua, Naalehu, Holualoa ; V in Pahala, Kailua Kona, Ookala, Honokaa, Hawaii National Park, Hakalau and IV in Kapaau, Honomu, Kamuela, Waikoloa, Pepeekeo, Laupahoehoe, Paauilo, Papaikou, Hawi, Mountain View, Volcano, Papaaloa, Pahoa, Kula, Fort Shafter, Hilo, Nonole, Kurtistown, Keaau, Wailuku, Paia, Kihei, with lesser shaking throughout much of the remaining Hawaiian Islands. EMSC reported the mainshock was strongly felt with long duration in
Hawaii at Kailua-Kona, Hawaiian Ocean View, Kalaoa, Naalehu, Volcano, Fern Forest, Honoka'a, Papaiikou, Pepeeleo, Ainaloa, Hawaiian Paradise Park, Kihei, Haiku-Pauwela, Kahului, Kaanapali Landing, Napili-Honokowai, East Honolulu, Honolulu, Kaneohe, Village Prk, Waipi'o Acres, Waianae, Lawai.
The last earthquake in the area of Hawaii of M>=6 occurred on October 10, 2021
with M 6.2. The strongest in the past 35 years were an M 6.9 on May 4, 2018 and an M 6.7
on October 15, 2006. At the time of the M 6.9 on May 4, 2018 this summary noted:
"A major earthquake of M 6.9-7.0 hit the island of Hawaii today after several days
of increasing seismicity and volcanism in the area. This included the strongest
quake of the series which occurred about an hour prior to the mainshock with M 5.4. NEIC reported damage with
this earthquake but no major tsunami was observed. The earthquake occurred
within about 15 minutes of local solar noon and was probably promoted by tidal
stresses which maximize at this hour.
NEIC reported the mainshock was felt throughout the area of Hawaii. Intensity VI-VII was
felt within about 100 km of the epicenter at Pahoa, Mountain View, Kurtistown, Volcano, Keaau, Hawaii National Park, Hilo, Papaikou, Pepeekeo, Pahala, with lesser shaking within about 500 km of the epicenter.
An M 5.3 followed about 40 km north of the epicenter of the major quake. NEIC reported it was felt with intensity IV in Hilo and II-III in Volcano, Pahoa, Naalehu, Mountain View, Kurtistown, Captain Cook, Keaau, Papaiko, Paauilo and within about 100 km of the epicenter. The strongest aftershock were of M 4.6-5.0. They were generally reported felt with intensity II-III in Pahoa, Keaau, Papaikou, Hilo, Pepeekeo, Kamuela and Kihei, Hawaii.: (May 4, 2018)
This epicenter is near the sub-solar latitude (near 17-18 North on May 23).
This summary has argued in previous issues that vertical tidal stresses
which are maximized near sub-solar conditions (sun directly overhead at
local solar noon) can help promote stronger seismicity than normal on
those days and time, and this appears to be the case in this situation
in Hawaii.
Spectacular fountains of lava and eruptive material also continued in
the area of Kilauea east of today's epicenter in an ongoing eruption
at that volcano in Hawaii.
O: 23MAY2026 07:46:01 19.4N 155.8W ML=6.0 NEIC ISLAND OF HAWAII
A moderately strong M 5.6 also occurred earlier in the day in the area of the
Fox Islands, Aleutians. Like the event in the Admiralty Islands (see above) this epicenter was near
local solar midnight when the M2.3 flare occurred and may have been
promoted by SFE from that flare. NEIC reported shaking may have occurred with
intensity up to V in Atka, Alaska.
O: 22MAY2026 12:16:14 52.5N 171.7W ML=5.6 NEIC FOX ISLANDS, ALASKA
NEIC reported an earthquake of M 4.9 in the Fox Islands, Alaska was felt with intensity up to II-III in the area(s) of the Fox Islands, Alaska with possible intensity III near Nikolski.
O: 23MAY2026 09:03:09 52.4N 169.5W ML=4.9 NEIC FOX ISLANDS, ALASKA
NEIC reported an earthquake of M 5.7 in the Southeast Indian Ridge was not felt in this remote area of the Southeast Indian Ridge.
This is the strongest earthquake in the Southeast Indian Ridge since an
M 6.6 on April 16, 2025. At the time this summary noted:
"The strongest earthquake of the day was an M 6.6 in the southeast Indian Ridge southwest of Australia.
It was not reported felt in this remote area and like most strong earthquakes
on Ocean Ridges was not expected to produce a notable tsunami and no tsunami
waves were reported. It was followed by an M 5.2 aftershock 43 minutes later.
This event is the strongest earthquake within about 300 km of this epicenter
on the Southeast Indian Ridge since an M 6.6 on June 13, 2002, the only such
event in this region in the past 35 years. At the time this summary noted:
"A strong earthquake occurred in the southeast Indian Ridge this
morning. This event has initial Ms 6.5 (NEIS). This is one of the
largest events ever recorded in this section of the SE Indian
Ridge" (June 13, 2002)
This epicenter in the Indian Ridge - at 99E longitude - was at local solar midnight
when the geomagnetic storm began at 17:10 UT and was likely promoted by geomagnetic effects." (April 16, 2025)
This epicenter is at the seventh node (53 degrees) from the Molucca Sea
and may have been promoted by energy from that source.
This earthquake occurred within a couple of minutes of local solar noon
and was likely promoted by tidal and/or geomagnetic effects which maximize
near this hour.
O: 23MAY2026 05:41:34 47.5D 100.0E ML=5.7 NEIC SOUTHEAST INDIAN RIDGE
NEIC reported an earthquake of M 4.2 in Central Italy was felt with intensity up to II-III in the area(s) of Central Italy with IV in Montappone, Marken.
EMSC reported it was felt near Perugia and Camerino, Italy.
O: 23MAY2026 00:13:33 43.0N 13.2E ML=4.2 NEIC CENTRAL ITALY
NEIC reported an earthquake of M 3.3 in Northern California was felt with intensity up to IV in the area(s) of Northern California with III in Tahoe City and Camino and II in Truckee, Soda Springs, Foresthill, Georgetown , Pollock Pines, Somerset and Placerville and in Incline Village, Nevada.
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.
O: 22MAY2026 19:45:59 39.4N 120.1E ML=3.3 NEIC NORTHERN CALIFORNIA
NEIC reported an earthquake of M 2.9 in Oklahoma was felt with intensity up to II-III in the area(s) of Oklahoma in Stillwater, Perry.
O: 22MAY2026 16:18:09 36.2N 97.1W ML=2.9 NEIC OKLAHOMA
NEIC reported an earthquake of M 4.5 in Costa Rica was felt with intensity up to II-III in the area(s) of Costa Rica in Gulfito Puntarenas.
O: 22MAY2026 09:20:04 9.9N 83.4W ML=4.5 NEIC COSTA RICA
EMSC reported an earthquake of M 4.0 in Strait of Gibraltar was felt with intensity up to IV in the area(s) of Strait of Gibraltar in Casablanca, Morocco.
O: 23MAY2026 01:37:22 35.8N 7.6W ML=4.0 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 May 22, 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)
-------------------------------------------------------------------------
4300 0022 0032 0048 C2.8 (May 22, 2026) 3.4E-03
4310 0254 0302 0318 B9.0 (May 22, 2026) 1.3E-03
Peru M 4.0 03:09 UT
4320 0323 0334 0349 C1.9 (May 22, 2026) 2.3E-03
Guerrero M 4.1 03:44 UT
4330 0452 0459 0505 C1.9 (May 22, 2026) 1.5E-03
Atacama, Chile M 4.0 04:53 UT
4350 0640 0652 0703 C2.1 (May 22, 2026) 2.4E-03
Guerrero M 4.0 07:09 UT
South Africa M 3.0 07:07 UT
4370 0731 0736 0740 B9.4 (May 22, 2026) 5.3E-04
Hawaii M 6.0 07:46 UT
Bew Guinea M 4.4 07:41 UT
4390 0949 1001 1003 C1.4 (May 22, 2026) 1.7E-03
4410 1003 1029 1101 M2.3 (May 22, 2026) 5.3E-02
Hawaii M 4.0 10:56 UT
4420 1255 1301 1305 C1.5 (May 22, 2026) 9.6E-04
Southern Texas M 2.3 12:59 UT
Crete M 4.4 13:34 UT
4430 2011 2018 2035 C1.1 (May 22, 2026) 1.6E-03
4450 2125 2133 2138 C1.5 (May 22, 2026) 1.1E-03
Northern Colombia M 4.3 21:26 UT
FOX Is. M 5.3 21:49 UT
4460 2252 2255 2258 C1.3 (May 22, 2026) 4.7E-04
Fiji M 4.0 22:52 UT
4470 2333 2350 2358 C1.6 (May 22, 2026) 1.9E-03
Samoa M 4.9 23:54 UT
GEOMAGNETIC FIELD: quiet May 23-25. Solar M-flare chance: 30% X-class: 5% proton storm: 5%
AP Indicies: global: 6, high: 9, mid-latitude: 5, time of max k: 10:00-12:00 UT; Max k: 5 Global Kp 2.67 2100-2400, May 22; Sunspot Number: 67; Radio Flux: 124
May 22, 2026
Notable earthquakes and events:
A strong M2.3 solar flare (#4410) occurred on May 22, 2026 with maximum
output (as per SWPC data) at 10:29 UT. This is the strongest solar flare
reported by SWPC since an M5.7 (#2450) on May 10, 2026, two weeks ago.
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
4410 1003 1029 1101 M2.3 (May 22, 2026) 5.3E-02
Sudden strong solar flares can help to trigger volcanism and seismicity in areas
which are near local solar noon or local solar midnight at the time of
their occurrence or concurrent with the flare. The peak of this flare
occurred at 10:29 UT. Areas at local solar noon at this hour are in Central
Europe near 22 East longitude while areas at local solar midnight
are near 156 West longitude and include Alaska and Hawaii. In the current circumstances
an M 5.7 earthquake in the Admiralty Islands of Papua New Guinea
occurred at 10:03 UT at the start of this flare. This is part of an
ongoing submarine volcanic eruption which began in early May, 2026 in the Admiralty Islands.
This summary has been following this eruption for example as:
"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." (May 8, 2026)
"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." (May 9, 2026)
A M 5.1 earthquake on May 17, 2026 was also closely associated with
a solar flare and was discussed in this summary at the time as:
Flare # START MAX END CLASS DATE Flux (Jm-2)
-------------------------------------------------------------------------
3770 0745 0757 0809 B9.0 (May 17, 2026) 1.2E-03
Admiralty Is. M 5.1 07:52 UT
O: 22MAY2026 10:08:23 2.9S 147.7E ML=5.7 NEIC ADMIRALTY ISLANDS, PAPUA NEW GUINEA
A strong M 6.0 earthquake also occurred at the longitude at local solar
midnight when this solar flare occurred. A fluctuation in the GOES-18 magnetometer at 137 West longitude
which began at about 21:29 UT and finished at 22:47 UT on May 22, 2026
occurred when this longitude and latitude in Hawaii were very close to
exact sub-solar conditions and may have been promoted by that geomagnetic event.The event at 155 West longitude was widely
felt in Hawaii and occurred near the largest volcano on planet Earth - Launa Loa.
It could help initiate enhanced seismicity and volcanism in the Island of
Hawaii. NEIC received more than 6000 felt reports from citizens regarding the effects of this quake.
These include intensities VII in Hawaii at Captain Cook; VI in Kealakekua, Naalehu, Holualoa ; V in Pahala, Kailua Kona, Ookala, Honokaa, Hawaii National Park, Hakalau and IV in Kapaau, Honomu, Kamuela, Waikoloa, Pepeekeo, Laupahoehoe, Paauilo, Papaikou, Hawi, Mountain View, Volcano, Papaaloa, Pahoa, Kula, Fort Shafter, Hilo, Nonole, Kurtistown, Keaau, Wailuku, Paia, Kihei, with lesser shaking throughout much of the remaining Hawaiian Islands. EMSC reported the mainshock was strongly felt with long duration in
Hawaii at Kailua-Kona, Hawaiian Ocean View, Kalaoa, Naalehu, Volcano, Fern Forest, Honoka'a, Papaiikou, Pepeeleo, Ainaloa, Hawaiian Paradise Park, Kihei, Haiku-Pauwela, Kahului, Kaanapali Landing, Napili-Honokowai, East Honolulu, Honolulu, Kaneohe, Village Prk, Waipi'o Acres, Waianae, Lawai.
The last earthquake in the area of Hawaii of M>=6 occurred on October 10, 2021
with M 6.2. The strongest in the past 35 years were an M 6.9 on May 4, 2018 and an M 6.7
on October 15, 2006. At the time of the M 6.9 on May 4, 2018 this summary noted:
"A major earthquake of M 6.9-7.0 hit the island of Hawaii today after several days
of increasing seismicity and volcanism in the area. This included the strongest
quake of the series which occurred about an hour prior to the mainshock with M 5.4. NEIC reported damage with
this earthquake but no major tsunami was observed. The earthquake occurred
within about 15 minutes of local solar noon and was probably promoted by tidal
stresses which maximize at this hour.
NEIC reported the mainshock was felt throughout the area of Hawaii. Intensity VI-VII was
felt within about 100 km of the epicenter at Pahoa, Mountain View, Kurtistown, Volcano, Keaau, Hawaii National Park, Hilo, Papaikou, Pepeekeo, Pahala, with lesser shaking within about 500 km of the epicenter.
An M 5.3 followed about 40 km north of the epicenter of the major quake. NEIC reported it was felt with intensity IV in Hilo and II-III in Volcano, Pahoa, Naalehu, Mountain View, Kurtistown, Captain Cook, Keaau, Papaiko, Paauilo and within about 100 km of the epicenter. The strongest aftershock were of M 4.6-5.0. They were generally reported felt with intensity II-III in Pahoa, Keaau, Papaikou, Hilo, Pepeekeo, Kamuela and Kihei, Hawaii.: (May 4, 2018)
This epicenter is near the sub-solar latitude (near 17-18 North on May 23).
This summary has argued in previous issues that vertical tidal stresses
which are maximized near sub-solar conditions (sun directly overhead at
local solar noon) can help promote stronger seismicity than normal on
those days and time, and this appears to be the case in this situation
in Hawaii.
Spectacular fountains of lava and eruptive material also continued in
the area of Kilauea east of today's epicenter in an ongoing eruption
at that volcano in Hawaii.
O: 23MAY2026 07:46:01 19.4N 155.8W ML=6.0 NEIC ISLAND OF HAWAII
The strongest earthquake in the world on May 21, 2026 was an M 5.9 in the Molucca
Sea of Indonesia. This is an aftershock of the M 7.4 in the Molucca Sea of April 1, 2026,
the largest to date since April 2 when a M 6.3 aftershock occurred. NEIC reported it may have been felt with intensity up to
IV near Bitung, Indonesia.
O: 22MAY2026 01:05:08 1.0N 126.1E ML=5.9 NEIC MOLUCCA SEA
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 the Fox Islands, Alaska with possible intensity II in Nikolski, Alaska.
O: 22MAY2026 06:33:37 51.9N 169.1W ML=4.7 NEIC FOX ISLANDS, ALASKA
NEIC reported earthquakes of M 3.9 and 2.5 off the coast of Northern California was felt with intensity up to II-III in the area(s) of Northern California with III in Petrolia, Ferndale, Whitethorne, Hydesville and Eureka.
The larger of these - the M 3.9 occurred near local solar noon and was probably
promoted by tidal and/or geomagnetic effects which maximize near this hour.
O: 22MAY2026 05:29:15 40.8N 124.1W ML=2.5 NEIC NORTHERN CALIFORNIA
O: 21MAY2026 19:00:10 40.4N 125.0W ML=3.9 NEIC OFF COAST OF NORTHERN CALIFORNIA
NEIC reported an earthquake of M 3.3 in Baja California was felt with intensity up to II-III in the area(s) of Baja California in Heber, California and Yuma, Arizona.
O: 22MAY2026 01:10:42 32.4N 115.3W ML=3.3 NEIC BAJA CALIFORNIA
NEIC reported an earthquake of M 4.9 in Southern Iran may have been felt with intensity up to II-III in the area(s) of Bandar Abbas, Iran.
This is probably a natural earthquake as the area is seismic. Some of the
current activity, however may be triggered by hostilities in the area.
O: 21MAY2026 09:56:26 27.2N 55.7E ML=4.9 NEIC SOUTHERN IRAN
EMSC reported an earthquake of M 4.7 in The Canary Islands, Spain was felt with intensity up to II-III in the area(s) of The Canary Islands, Spain. EMSC reported strong shaking in the Canary Islands in Las Palmas de Gramn Canaria, Costa, Calma, Pajara, Moya, La Olivia, Maspalomas, Corraleio.
Resident were greatly distressed by this earthquake and fled their homes for fear of the shaking.
The last (and only) earthquake in the Canary Islands within about 200 km of this epicenter with M>=4.7
was recorded on November 8, 2008 with M 4.7. No earthquakes of larger magnitude
have hit this region in at least 35 years. Some geoscientists are concerned
that this could help trigger a regional volcanic eruption with potential
for a major Atlantic tsunami but indications of this are not yet forthcoming.
The antipode is south of Vanuatu where recent ocean storms and earthquakes
may have helped promote this event near the antipode in the Canary Islands.
This epicenter is about 104 degrees from Honshu Japan and at the third node (120 degrees)
from Malaysia and from the M 6.6 in the South East Pacific Rise yesterday and may have been promoted by energy from those sources.
O: 22MAY2026 08:50:19 28.4N 14.9W ML=4.7 NEIC CANARY ISLANDS
NEIC reported an earthquake of M 3.7 in Crete, Greece was felt with intensity up to II-III in the area(s) of Crete in Makry-Gialos, Ferma, Ierapetra, Agopo Theodoroi, and Stalos.
This epicenter was near local solar midnight when this earthquake occurred
and may have been promoted by tidal and/or geomagnetic stresses.
O: 21MAY2026 20:36:30 34.9N 25.9E ML=3.7 EMSC CRETE, GREECE
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.
O: 21MAY2026 20:38:12 29.8S 71.3W ML=4.0 EMSC COQUIMBO, 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 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)
-------------------------------------------------------------------------
4240 1309 1321 1324 C5.5 (May 21, 2026) 2.1E-03
4250 1629 1637 1640 C1.0 (May 21, 2026) 7.3E-04
4260 1804 1814 1819 C8.3 (May 21, 2026) 5.0E-03
Caribbean Sea M 4.2 18:23 UT
4270 1819 1825 1830 C9.5 (May 21, 2026) 6.4E-03
Caribbean Sea M 4.2 18:23 UT
4280 1941 1958 2035 C1.2 (May 21, 2026) 3.5E-03
Fox Is. M 4.3, 3.0 20:10, 20:15 UT
4290 2304 2310 2315 C1.3 (May 21, 2026) 9.1E-04
GEOMAGNETIC FIELD: quiet May 23-24 active May 22. Solar M-flare chance: 30% X-class: 5% proton storm: 5%
AP Indicies: global: 7, high: 10, mid-latitude: 6, time of max k: 13:00-15:00 UT; Max k: 4 Global Kp 3.00 0000-0300, May 21; Sunspot Number: 76; Radio Flux: 118
May 21, 2026
Notable earthquakes and events:
A strong M 6.6 earthquake hit the South East Pacific Rise today at 122 West
longitude. This event was not reported felt in this remote area and
a tsunami is unlikely. EMSC shows an aftershock of M 5.2 about 53 minutes
after the mainshock. The mainshock is the strongest recorded within
about 300 km of this epicenter since an M 6.6 on August 6, 2001 nearly
25 years ago.
This epicenter is at 122 West longitude, a longitude which was particularly stressed
during the new moon of May 16 as reported in previous issues of this summary:
"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 14-28, 2026)
This epicenter is also nearly antipodal to a highly unusual pair of earthquakes
that struck on May 5 in the Ural Mountains of Russia. At the time this
summary noted:
"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.
...
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 satellite 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" (May 5, 2026)
Today's epicenter in the East Pacific Rise is at the eighth node (45 degrees) from the South Geomagnetic
Pole and at 144 degrees from the North Geomagnetic Pole and was probably
promoted by energy of the recent geomagnetic storm concentrated near
those points on the earth's surface. It is also at 103 degrees from
the Molucca Sea (node 7).
O: 20MAY2026 17:43:02 56.0S 122.3W ML=6.6 NEIC SOUTHERN EAST PACIFIC RISE
O: 20MAY2026 18:36:39 54.8S 118.6W MB=5.0 EMSC SOUTHERN EAST PACIFIC RISE
O: 20MAY2026 18:36:17 55.7S 123.9W MW=5.2 EMSC SOUTHERN EAST PACIFIC RISE
O: 20MAY2026 17:43:01 56.0S 122.5W Mw=6.6 EMSC SOUTHERN EAST PACIFIC RISE
O: 20MAY2026 18:36:39 54.8S 118.6W ML=5.9 NEIC SOUTHERN EAST PACIFIC RISE
An M 5.7 at the same latitude as the M 6.6 in the East Pacific Rise - this in the South Sandwich Islands - followed
the event in the East Pacific Rise. It too was not reported felt in this
remote area.
This epicenter is at the sixth node (60 degrees) from the South Geomagnetic
Pole and at 149 degrees from the North Geomagnetic Pole and was probably
promoted by energy of the recent geomagnetic storm concentrated near
those points on the earth's surface.
O: 20MAY2026 23:00:58 56.1S 28.1W ML=5.7 NEIC SOUTH SANDWICH ISLANDS
O: 20MAY2026 23:00:58 56.1S 27.9W MW=5.7 EMSC SOUTH SANDWICH ISLANDS REGION
O: 21MAY2026 08:37:02 56.0S 27.5W mb=4.7 EMSC SOUTH SANDWICH ISLANDS REGION
O: 21MAY2026 08:37:05 56.1S 27.7W ML=4.7 NEIC SOUTH SANDWICH ISLANDS
Another unusual regional earthquake occurred with M 4.8 in the Southern East Pacific Rise about 11 hours
after the M 6.6 mainshock. This event was also not felt in this remote area.
The last earthquake with M>=4.8 within about 200 km of this epicenter
in the East Pacific Rise occurred about 100 km to the south of this on January 30, 2026 - an event also associated with an M 6.0 in the South Sandwich Islands.
The last within 100 km of today's epicenter occurred as an M 5.3 on June 28, 2021.
At that time this summary noted:
"The earthquake in the southern East Pacific Rise of M 5.3 was the strongest within
about 250 km of this epicenter since an M 6.7 on May 19, 2021 and is an aftershock
of that event." (June 28, 2021)
This epicenter is at the fifth node (72 degrees) from the South Geomagnetic
Pole and at the third node (120 degrees) from the Molucca Sea and Honshu and the north Geomagnetic
Pole and at the sixth node (60 degrees from Tonga and was probably promoted
by constructive interference of energy from those sources.
O: 21MAY2026 04:11:59 33.3S 109.3W ML=4.8 NEIC SOUTHERN EAST PACIFIC RISE
O: 21MAY2026 04:11:59 33.4S 109.3W MB=4.8 EMSC SOUTHERN EAST PACIFIC RISE
A moderate M 4.1 earthquake occurred in Southern Italy today. EMSC reported it was widely felt
in Italy at Procida, Pozzuoli, Masseria Veccha Ovest, Posillipo,Quarto, Festinese, Fuorigotta, Chiaia, Vomero, Arenella, San Ferdinando, Avvocata, Villaricca, Giugliano in Campania, San Carlo All'Arena.
NEIC reported it was felt with intensity Vin Italy at Pozzuoli, and II in Naples, Campania.
This appears to be part of the current seismic unrest in the area of Naples.
The last shallow focus earthquake in this area with M>=4.1 occurred as an M 4.4
on May 13, 2025 a year ago. At the time this summary noted:
"An earthquake of M 4.4 shook the region of Naples, Italy today causing concern
of a coming volcanic event among residents. NEIC reported maximum intensity IV in Campania at Naples with III in Casoria and II in Sorrento, Italy.
EMSC reported moderate shaking in the Naples, Italy area at Pozzuoli with slight damage, Quarto, Naples, Casoria, Aversa, San Giorgio a Cremano, Frattamaggiore, Afragola, Trecase, Minturno, Belvedere Marittimo.
This is the strongest earthquake in the area of central Italy within about 150 km of this epicenter since an M 4.7 on March 28, 2023.
An M 4.2 hit the Naples area on March 13, 2025. At the time this summary noted:
"NEIC reported an earthquake of M 4.2 in Naples, Italy was felt with intensity up to II-III in the area(s) of Naples, Italy with V in Pozzuoli, Campania; IV in Monte di Procida, Naples, Quarto, III in Bacoli, Orta di Atellaand San Giorgio a Cermano and in Penna Sant' Andrea Abruzzen, Italy.
EMSC reported this event at M 4.4 was felt strongly in Italy at Monte di Procida, Naples, Quarto, Afragola, Frattamaggiore, Pollena Trocchia, Pomigliano d'Arco, Acerra, Boscoreale, Nola.
This appears to be the strongest earthquake west of Naples in at least 40 years. The press
reported it was preceded by a loud earthquake noise. A lot of damage to facades
and ceilings was reported with the quake and in Bagnoli some people were trapped
in their houses. A ceiling collapse in Pozzuoli temporarily trapped a resident.
A series of aftershocks followed inflicting additional damage. An minor eruption of
Mount Vesuvius or Campi Flegrei is expected in the near future. The earthquake
occurred near local solar midnight and may have been promoted by strong
tidal stresses associated with the full moon and eclipse of March 14." (March 13, 2025, May 13, 2025)
Like the earthquake in the Southern East Pacific Rise, this epicenter
in Italy is at 105 degrees from the Molucca Sea and at 52 degrees (Node 7)
from the North Geomagnetic pole and was probably promoted by constructive
energy interference and recent geomagnetic storms associated with those areas.
O: 21MAY2026 03:50:52 40.8N 14.1E ML=4.1 NEIC SOUTHERN ITALY
O: 21MAY2026 03:50:52 40.8N 14.1E MB=4.1 EMSC SOUTHERN ITALY
EMSC reported an earthquake of M 5.2 in Flores, Indonesis was felt with intensity up to II-III in the area(s) of Flores, Indonesia in Labuan Bajo.
O: 20MAY2026 10:28:49 8.1S 119.2E MB=5.2 EMSC FLORES REGION, INDONESIA
NEIC reported an earthquake of M 4.4 in Near Island, Alaska was felt with intensity up to II-III in the area(s) of Near Island, Alaska near Attu Station.
This was the largest earthquake located in the U.S. or Canada today.
This event is located at the tenth node (36 degrees) from the North Geomagnetic
Pole and at the third node (120 degrees) from the South Geomagnetic Pole
and may have been promoted by energy of the recent geomagnetic storms
concentrated at the poles.
O: 21MAY2026 06:07:48 51.1N 173.8E ML=4.4 NEIC NEAR ISLANDS, ALASKA
NEIC reported an earthquake of M 2.7 in Southern Utah was felt with intensity up to II-III in the area(s) of Southern Utah at Hurricane.
O: 20MAY2026 23:21:35 37.1N 112.9W ML=2.7 NEIC SOUTHERN UTAH
An unusual earthquake of M 3.5 (NEIC) to M 3.9 (EMSC) occurred near Copenhagen, Denmark today.
NEIC reported it with M 3.5 in Denmark was felt with intensity up to IV in the area(s) of Denmark at Havdrup, Greve Strad,Ronnede, Stenlille, Ishoj, Koge, Tune, and III in Stroby Egede, Harlev and Fensmark.
EMSC reported a deep rumble and wild shaking in Denmark at Ejby, Koge, Bjaeverskov, Ejby, Stroby Egede, Ajaeverskov, Solrod, Havdrup, and as far as Snoghoj and Haderslev, Denmark up to 170 km from the epicenter.
The last earthquake in Denmark within about 200 km of this epicenter with
M>=3.5 was recorded by NEIC as an M 4.2 on August 6, 2012. A similar event occurred
on December 16, 2008. These are the only two such events listed in this
area in the past 35 years. At the time of the August, 2012 event this summary
noted:
"An unusual earthquake in the border region between Denmark and Sweden with M 4.4 today.
NEIC reported this earthquake of M 4.4 in Denmark was felt with intensity II-III in the area(s) of
Farum, Frederiksborg, Lejre, Roskilde, Odense, Fyn, Denmark and in Halland Sweden
at Falkenberg and intensity IV in Halmstad, Sweden. Local news reported strong
shaking woke many in Angelholm, Skogaby, Laholm, and surrounding areas waking
many. At least 30 people reported the quake in Halmstad reporting shaking windows
and furniture. No damage was immediately reported and there were no reported
casualties. Swedish seismologists indicated earthquakes of this size hit
the general area about every 10 years. The last earthquake to occur within
200 km of this epicenter with M>4 was an M 4.3 on December 16, 2008 about
250 km to the southeast. Only three earthquakes of similar or larger size
have been recorded in this area in the past 100 years - on October 31, 1930
(M 4.5); June 15, 1985 (M 4.4-5.0) and May 13, 1987 (M 4.7). None of these
were followed immediately by great quakes but the events in 1930 and 1985
occurred about three months before earthquakes of M>8 in Mexico and the
May, 1987 event was followed by an M 7.9 six months later in southeastern
Alaska." (August 6, 2012)
and on December 16, 2008 this summary reported:
"Two unusual earthquakes today hit in the regions of South Carolina (M 3.6)
and in the area of northern Denmark and Sweden (M 4.4). The event in Sweden
is unusual for the current seismicity of the area for its size. Events
of M>=4 are rare in Sweden. It is likely an earthquake related to uplift
from the last ice age in the area. Today's event was widely felt throughout
southern Sweden with intensity IV felt in Eslav, Frederikssund, Helsinge,
Humblebak, Staffanstorp, and Ystad. This was the biggest earthquake in
Denmark in the past 80 years and the largest in Sweden in more than 100 years. It woke many people in their beds moving
on the floor. Aftershocks were reported as far as Poland. No one was injured
and no major damage was reported. The quake was located about 36 mile SE
of Sweden's third largest city Malmoe. Cracks may have appeared in some building facades.
An earthquake on October 23, 1904 was the last large quake to hit Sweden.
Stockholm News reported the quake was felt in the regions of Skane, Halland, Blekinge
and in Smaland as well as in the Danish capital Copenhagen." (December 16, 2008)
Like earthquakes in the South East Pacific Rise, Botswana and Italy today
this epicenter is located at 103 degrees from the Molucca Sea and was
probably promoted by energy from that source
O: 20MAY2026 14:14:33 55.4N 12.0E ML=3.5 NEIC DENMARK
O: 20MAY2026 14:14:33 55.5N 12.1E ML=3.9 EMSC DENMARK
NEIC reported an earthquake of M 3.8 in Southern Alaska was felt with intensity up to II-III in the area(s) of Southern Alaska in Ninilchik, Clam Gulch and Homer.
O: 20MAY2026 14:03:35 60.2N 152.3W ML=3.8 NEIC SOUTHERN ALASKA
EMSC reported an earthquake of M 2.9 in South Africa was felt with intensity up to IV in the area(s) of South Africa at Gaborone, Botswana.
Like earthquakes in the South East Pacific Rise, Denmark and Italy today
this epicenter is located at 103 degrees from the Molucca Sea and was
probably promoted by energy from that source (see above).
O: 20MAY2026 10:49:17 24.8S 26.1E ML=2.9 NEIC SOUTH AFRICA
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 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)
-------------------------------------------------------------------------
4140 0235 0245 0253 B8.7 (May 20, 2026) 8.9E-04
Ryukyu Is. M 5.9 02:46 UT
West Chile Rise M 5.0 02:46 UT
4160 0325 0332 0337 B8.7 (May 20, 2026) 6.4E-04
4170 0412 0443 0513 C1.0 (May 20, 2026) 3.5E-03
Banda Sea M 4.0 04:19 UT
4200 0959 1009 1017 C1.0 (May 20, 2026) 9.7E-04
Flores M 5.2 10:28 UT
GEOMAGNETIC FIELD: active May 22 quiet May 23 unsettled May 21. Solar M-flare chance: 20% X-class: 5% proton storm: 5%
AP Indicies: global: 8, high: 11, mid-latitude: 8, time of max k: 00:00-06:00 UT; Max k: 4 Global Kp 3.00 0000-0300, May 20; Sunspot Number: 67; Radio Flux: 114
May 20, 2026
Notable earthquakes and events:
UPDATE:
A strong M 6.6 earthquake hit the South East Pacific Rise today at 122 West
longitude. This event was not reported felt in this remote area and
a tsunami is unlikely. This earthquake is the strongest recorded within
about 300 km of this epicenter since an M 6.6 on August 6, 2001 nearly
25 years ago.
This epicenter is at 122 West longitude, a longitude which was particularly stressed
during the new moon of May 16 as reported in previous issues of this summary:
"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 14-28, 2026)
This epicenter is at the eighth node (45 degrees) from the South Geomagnetic
Pole and at 144 degrees from the North Geomagnetic Pole and was probably
promoted by energy of the recent geomagnetic storm concentrated near
those points on the earth's surface. It is also at 103 degrees from
the Molucca Sea (node 7).
O: 20MAY2026 17:43:02 56.0S 122.6W ML=6.6 NEIC SOUTHERN EAST PACIFIC RISE
An M 5.7 at the same latitude - this in the South Sandwich Islands - followed
the event in the East Pacific Rise. It too was not reported felt in this
remote area.
This epicenter is at the sixth node (60 degrees) from the South Geomagnetic
Pole and at 149 degrees from the North Geomagnetic Pole and was probably
promoted by energy of the recent geomagnetic storm concentrated near
those points on the earth's surface.
O: 20MAY2026 23:00:58 56.1S 28.1W ML=5.7 NEIC SOUTH SANDWICH ISLANDS
The strongest earthquake of the day was an M 5.8-6.2 (initial estimate) in the Ica region of Central Peru.
EMSC reported strong shaking in Peru at Ica, Paracas. Pisco, Lucanas, Cieneguilla, Santiago de Surco, La Molina, San Isidro, and Independencia.
NEIC reported intensity V in Ica, Peru at Vista, Subtanjalla and Ica; IV in Los Aquiljes, Pisco and III in Marcona, and in the Lima area at Lima, Santa Maria and San Luis.
Press accounts from AP reported at least 27 were injured and many building were damaged
but there were no reports of deaths resulting from the quake. Internet
videos show broken plaster and crumbled buildings and widespread damage as well as landslides in the
area. This is the strongest earthquake in Peru within about 200 km of this epicenter
since an M 6.0 on May 17, 2025, one calendar year ago. At the time this summary noted:
"A strong earthquake of M 6.0 occurred in Cenral Peru on the morning of May 17.
NEIC reported it was felt with intensity VI in Ayacucho, Peru with minor damage and intensity VI in Puquio and V in Ica at Santiago, Peru. Intensity IV in Ica was also felt at Subtanjalla and III in Lima and Pisco with II in Cusco.
EMSC reported strong shaking in Ayacucho, Ica, Lircay (for 30 seconds); Jose Luis Bustamante and Rivero, Arequipa, Chocaya, San Isidro, Asia.
This epicenter is located on the geomagnetic equator and is at 99-100 degrees
from the South Geomagnetic Pole as well as the New Zealand quake of March 25, 2025 (M 6.8) and the
Macquarie Island quake of April 29, 2025 and at 108 degrees from the North Geomagnetic Pole and may have been promoted by
energy associated with those sources. Charged particles entering the earth's
environment are drawn to the north and South geomagnetic poles disturbing
the solid earth in much the same was as an earthquake. These effects are
often strongest at or near 103 degrees from the poles but can vary by a few degrees when coincidental
distances from similar sources and waveforms can cause constructive energy interference.
The last earthquake of hit Peru within about 150 km of today's epicenter with
M>=6.0 was an M 7.4 on June 28, 2024 about 100 km south of today's epicenter.
At the time this summary noted:
"A major M 7.2 earthquake occurred today off the west coast of Southern Peru. NEIC reported it was
felt with intensity up to IX in Atiquipa, Peru. EMSC reported strong to damaging
intensity in Southern Peru at Ica, Arequipa, Jose Luis Bustamante y Rivero, Pilcomayo, Villa El Salvador, Chorrilos, Surquillo, San Isidro, Jesus Maria, Magdalena Del Mar, Lima, Independencia, San Martin de Porres, Ventanilla, Alto Hospicio, and possible as far the north as Ecuador.
CENSIS reported intensity VI in Yauca, Caraveli, Arequipa, Peru. At least five were injured in this earthquake according to on-line news sources.
Power and Telephone service was out in some portions of southern Peru.
This is the strongest earthquake within about 250 km of this epicenter
since an M 8.4 on June 23, 2001 - an event closely associated with a total
solar eclipse on June 21, 2001 - and an M 7.7 on November 12, 1996 - the only such regional events
in the past 35 years. The earthquake in Peru today occurred 23 years after
the event of June 23, 2001 and was reviewed in the "HISTORY" section of this
summary on June 23, 2023 (and June 23, 2024) as:
"The earthquake killed at least 75 including at least 26 by a tsunami. Nearly 18,000 homes were destroyed and more than 35,000 damaged in Arequipa, Camana and Tacna while injuring nearly 2700. Besides the 26 killed by the tsunami an additional 64 were missing. Many historic buildings were damaged or destroyed at Arequipa. Landslides blocked many highways. The earthquake followed by several days a total eclipse of the sun in the area. A tsunami was generated with maximum height to 7 meters and inundated up to 1 km inland." (June 23, 2023)
Today's earthquake of M 7.2 is the strongest
...
A strong geomagnetic storm occurred today starting at about 14:00 UT and peaking at about 14:50 UT
The GOES 15 magnetometer registered a change in the field strength beginning at
about 80 NT and ending at about 130 nT (nanoTesla) 15 minutes later as this geomagnetic
storm hit. A strong earthquake of M 6.0 occurred with this storm on the geomagnetic
equator in Southern Peru at 16S 74W. This was an epicenter which this summary
had expected to see a strong earthquake at this time associated with geomagnetic
storms ,,," (June 28, 2024, May 17, 2025)
Today's earthquake occurred near local solar noon and was probably promoted
by tidal and/or geomagnetic stresses as it lies on the geomagnetic equator
and these stresses maximize near this hour. The epicenter is at 105 degrees
from the North Geomagnetic Pole and at 99 degrees from the South Geomagnetic
pole and likely saw geomagnetic effects associated with the geomagnetic
storm of the past several days. The earthquake occurred in conjuction with
a new geomagnetic storm sudden commencement. This storm reached its maximum
intensity with K of 6+ at high latitudes at the time of this earthquake.
O: 19MAY2026 17:57:55 14.1S 75.5W ML=5.8 NEIC NEAR THE COAST OF CENTRAL PERU
O: 19MAY2026 17:57:55 14.2S 75.5W MW=5.8 EMSC NEAR COAST OF CENTRAL PERU
O: 19MAY2026 22:18:30 14.3S 75.7W ML=4.1 EMSC NEAR COAST OF CENTRAL PERU
Several hours after the M 5.8 in Peru an M 5.0-5.5 was recorded in western
Uzbekistan north of eastern Iran. EMSC reported it was felt strongly in Uzbekistan in Jondor Shaharchasi, Bukhara, Konimex, Kogon Shahri, Tomdibuloq, Navoiy, Novyy Turtkul, !arshi, Tashkent and Salor with light shaking in Dushanbe, Tajikistan and in Turkmenabat, Turkmenistan.
NEIC reported intensity III in Buxoro, Uzbekistan at Gazli and Olot and II in Vavoiy.
The last earthquake in Uzbekistan within about 200 km of this epicenter with
equal or greater magnitude occurred as an M 5.1 on July 24, 2005 and an M 5.2
on May 25, 1995. No events of magnitude greater than M 5.2 have hit the area in the
pst 35 years. At the time of the July, 2005 event this summary noted:
"An earthquake of M 5.2-5.5 occurred in northwestern Uzbekistan several
hours after the Nicobar Is. event at 40-41 degrees from the epicenter of that
quak - a distance at which seismic activation may be expected following
strong earthquakes. This is the strongest earthquake located in the region
(37-44N 55-68E) since an event of M 5.4 on Jan. 18, 2001 and a similar
event of M 5.5 on April 20, 2000 (M 5.5.)." (July 24, 2005)
As with a number of other significant earthquakes in the past several
weeks, this earthquake Uzbekistan occurred with a strong excursion in the
geomagnetic field as measured on the GOES-18 magnetometer. This was recorded
as beginning within about a minute of 20:40 UT - the same time as the earthquake
in Uzbekistan. An arcjet maneuver was then performed repositioning the
satellite and normal operating conditions resumed by 22:47 UT. Other
similar incidents have been previously examined in this summary.
This epicenter is at the seventh node (51 degrees) from the North geomagnetic
pole and at the third node from the South Geomagnetic Pole and may have
been promoted by energy associated with the current geomagnetic storms.
It is also at the sixth node (60 degrees) from Honshu, Japan.
O: 19MAY2026 20:40:43 40.3N 63.1E ML=5.5 EMSC WESTERN UZBEKISTAN
A moderately strong M 5.4 earthquake also occurred today in Eastern Turkey. EMSC reported it was strongly felt in Turkey in Malatya, Battalgazi, Yazihan, Kahta, Adiyaman, Elazig, Siverek, Karakopru, Sanliurfa, Caglayancerit, and with moderate intensity at Bogurtlen, Pazarcik, Birecik, Nizip, Sehitkamil, Kahramanmaras, and as far as Hamah, Syria, Tripoli, Lebanon, Cyprus, among others.
NEIC reported this earthquake was felt with V in Turkey at Gaziantep with V and in Beirut, Lebanon with intensity II.
The last earthquake of M>=5.4 in eastern Turkey within about 200 km of this
epicenter was an M 6.0 on October 16, 2024. At the time this summary noted:
"Today's earthquake in Turkey follows a major series of geomagnetic storms
and may also have been promoted by geomagnetic effects as noted in previous
issues of this summary for example:
"The current geomagnetic storm - the strongest in the world since AP at high
latitudes occurred reached 91 and planetary AP reached 122 on August 8, 2024 -
continued today with high latitude AP 116. Severe storms are expected through
October 11 with minor storms October 12. Maximum Kp during the storm reached
Kp 9 - the highest of the scale around 18:00 UT shortly after the arrival
in the earth environment of the CME from the X9.0 flare of early October. Global seismic
conditions are expected to remain relatively quiet through the storm with
a likely temporary enhancement with the arrival of the CME early on October 10
and should increase significantly shortly after the end of the geomagnetic storm
on October 12-15." (October 10-12, 16, 2024)
"Aftershocks of the M 6.0 early on October 16, 2024 in eastern Turkey continued
today as well. These included an M 4.6 regional aftershock today.
EMSC reported this earthquake of M 4.6 in Central Turkey was felt with intensity up to IV in the area(s) of Central Turkey in Ahmetturangazi Osb, Kardesler, Cami-i-Kebir, Sularbasi, Mehmetpasa, Sahincili, Zumrut, Mithatpasa, Sahinali.
In part, in the previous issue of this summary it had been noted in this regard:
"The strongest earthquake in the world today was an M 6.0 in eastern Turkey. NEIC reported maximum intensity VII (with damage) was felt in Turkey at Elazig and Malatya with V in in Yesilyurt. Intensity IV was reported in Diyarbakir, Erzincan, Gaziantep with intensity II-III in Doganyol, Malatya and Sivric, Elazig and Mazidagi, Mardin, and Ordu, Turkey.
EMSC reported this event was widely and strongly felt in eastern Turkey at Bulgurlu, Zaviye, Atasehir, Dilek, Yesilyurt, Caydacira, Universite, Elazig, Dilek, Kirklar, Girne, Eskisaray, Adiyaman, Varlik, Aktuluk, Kuptepe, Yaslica, Yaytas, Yenikent, Atakent, Firat, Diclekent, Fabrika among others within about 400 km of the epicenter. Also reported lightly felt in Iraq, Syria, Georgia, Lebanon, Cyprus.
The mainshock was accompanied by a series of foreshocks and aftershocks suggesting
strong regional stresses at this time. This included an M 4.3 yesterday reported
in this summary as:
"NEIC reported this earthquake of M 4.3 in Eastern Turkey was felt with intensity up to IV in the area(s) of Eastern Turkey in Doganyol and Agin Elazig.
EMSC reported light shaking in Turkey at Hilalkent, Atasehir, Abdullah Pasa, Sursuru, Cumhuriyet, Universite, Rizaiye, Firat, Yurukselim." (October 15, 2024)
This is the strongest earthquake in the region of Europe or the Middle East
since February 20, 2023 when an M 6.3 occurred about 300 km southwest of today's
epicenter and February 6, 2023 when the last earthquake in eastern Turkey within about 200 km of today's epicenter
occurred as an M 6.0 on February 6, 2023 - an aftershock of the major events of M 7.8 and M 7.5
in the area of February 6, 2023 and is the strongest aftershock of that
activity since the M 6.0 of February 6, 2023." (October 16, 2024)
Today's earthquake, an M 4.7 in Bandar Abbas, Iran and an M 4.8 near Nurabad, Iran
earlier in the day are all near a major subduction zone fault running through southern Iran
to eastern Turkey. A strong earthquake is possible on this fault
which may have been weakened due to explosions in the current hostilities.
O: 20MAY2026 06:00:16 38.3N 38.6E ML=5.4 EMSC EASTERN TURKEY
O: 19MAY2026 11:50:29 34.0N 47.8E ML=4.9 EMSC WESTERN IRAN
O: 19MAY2026 23:40:09 27.2N 55.8E ML=4.7 NEIC SOUTHERN IRAN
A strong earthquake in the world today also occurred as an M 5.9 in the Ryukyu Islands
of southwestern Japan. EMSC reported long shaking in Urasoe, Indonesia.
NEIC reported intensity V in Okinawa, Japan at Yomitan with III in Chatan, Ginowan, ?Nago, Okinawa, Ishikawa and Urasoe.
This epicenter is located at the fourth node (90 degrees) from the south
Geomagnetic Pole and at the sixth node (60 degrees) from the North Geomagnetic
Pole and was probably promoted by constructive interference of energy from those poles
associated with today's and previous day's geomagnetic storms.
O: 20MAY2026 02:46:25 27.5N 128.6E ML=5.9 EMSC RYUKYU ISLANDS, JAPAN
NEIC reported an earthquake of M 4.7 in Northern Mindanao, Philippines was felt with intensity up to II-III in the area(s) of Northern Mindanao, Philippines in Pilar, Caraga.
O: 20MAY2026 02:26:50 10.0N 125.8E ML=4.7 NEIC MINDANAO, PHILIPPINES
NEIC reported an earthquake of M 4.7 in Southern Iran was felt with intensity up to II-III in the area(s) of Southern Iran near Bandar Abbas.
This epicenter is on the Hormuz Strait, an area of intense conflict at
this time. While the area is seismic, the timing and location of today's event will
lead to speculation. At M 4.7 it is too large to be an explosion from a conventional
weapon but may have been triggered by explosions in the area during the
current conflict.
This epicenter is at the fifth node (72 degrees) from Honshu, Japan and from the Molucca
Sea and at the sixth node (60 degrees) from Malaysia and may have been promoted by energy from those sources.
O: 19MAY2026 23:40:09 27.2N 55.8E ML=4.7 NEIC SOUTHERN IRAN
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 Imperial.
O: 19MAY2026 22:23:42 32.8N 115.5W ML=2.7 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 2.7 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 Playa del Rey, Santa Monica, ?Hermosa Beach, Manhattan Beach and II in Los Angeles, El Segundo, Venice and Redondo Beach.
This earthquake occurred within several minutes of local solar noon and
may have been promoted by tidal and/or geomagnetic effects which maximize
near this hour. Such earthquakes can indicate areas where stress has built
up and a larger event is due shortly.
O: 19MAY2026 19:42:29 33.9N 118.5W ML=2.7 NEIC SOUTHERN CALIFORNIA
NEIC reported an earthquake of M 4.5 in Tajikistan was felt with intensity up to II-III in the area(s) of Tajikistan in Qurgonteppa, Khatlon.
O: 19MAY2026 17:42:56 38.1N 69.0E ML=4.5 NEIC TAJIKISTAN
NEIC reported an earthquake of M 4.8 in Vanuatu was felt with intensity up to II-III in the area(s) of Vanuatu at Vila Shefa.
O: 19MAY2026 14:18:39 17.8S 168.3E ML=4.8 NEIC VANUATU
The strongest earthquake in the U.S. or Canada today was an M 4.8 in central Alaska.
NEIC reported it was felt with intensity IV in Alaska at Ruby and II i Huslia and Shageluk.
This earthquake occurred near local solar midnight and may have been promoted
by tidal and/or geomagnetic effects which maximize near this time.
This is an unusual epicenter for Alaska. The last earthquake earthquake
with M>=4.8 within about 200 km of this epicenter occurred as an M 5.1 about
200 km to the northeast of this on January 6, 2019 but the only event in the
past 25 years within 200 km of this epicenter and with M>=4.8 occurred as an M 5.1 on November 13, 2003.
At the time this summary noted:
"The strongest activity in the U.S. or Canada continued today in the region
of Alaska. The largest of these events was an M 4.3-4.6 in the Huslia, northern
Alaska region" (November 13, 2003)
O: 19MAY2026 11:41:24 64.8N 156.0W ML=4.8 NEIC CENTRAL ALASKA
NEIC reported an earthquake of M 3.2 in Western Texas was felt with intensity up to II-III in the area(s) of Western Texas in Midland.
O: 19MAY2026 10:55:00 31.8N 101.8W ML=3.2 NEIC WESTERN TEXAS
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 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)
-------------------------------------------------------------------------
3980 0729 0740 0744 C2.1 (May 19, 2026) 1.0E-03
Bio-Bio Chile M 4.1 07:31 UT
4050 1642 1651 1705 C1.1 (May 19, 2026) 1.3E-03
4080 1944 2000 2009 C2.1 (May 19, 2026) 1.9E-03
4090 2111 2125 2140 C1.0 (May 19, 2026) 1.5E-03
4110 2158 2203 2207 C1.4 (May 19, 2026) 7.4E-04
GEOMAGNETIC FIELD: quiet May 20 and 22 unsettled May 21. Solar M-flare chance: 20% X-class: 5% proton storm: 5%
AP Indicies: global: 19, high: 47, mid-latitude: 18, time of max k: 09:00-20:00 UT; Max k: 6 Global Kp 4.00 1100-1900, May 18; Sunspot Number: 72; Radio Flux: 106
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
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 near 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
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
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 promnoted 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
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
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
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 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
A moderately larger 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
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 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 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 watch 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
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