UPDATED 4:M EDT -- A "severe" Magnitude 7.8 earthquake has just taken place in the north Pacific Ocean off the east coast of Russia's Kamchatka Peninsula. A TSUNAMI ADVISORY has been issued.
Details coming in . . . check back few minutes
This September 18, 2025, M7.8 earthquake that occurred east of Petropavlovsk-Kamchatsky, Russia is an aftershock of the M8.8 Kamchatka Peninsula earthquake that struck on July 29, 2025. The aftershock resulted from shallow reverse faulting.
As of its occurrence, the September 18, 2025, event is the largest aftershock recorded following the M8.8 mainshock, exceeding a nearby M7.4 aftershock that occurred on September 13.
At the earthquake’s location, the Pacific Plate is moving west-northwest relative to the North American Plate at a rate of approximately 80 mm/year. The earthquake’s location and faulting mechanism are consistent with faulting along the subduction zone plate interface of the Kuril-Kamchatka arc.
Although earthquakes are often represented as points on maps, events of this magnitude are better described as slip across a broad fault area. Reverse faulting earthquakes of this size typically involve rupture dimensions of approximately 100 km in length and 50 km in width.
TSUNAMI LIKELY
ZCZC
WEPA40 PHEB 181905
TSUPAC
TSUNAMI MESSAGE NUMBER 1
NWS PACIFIC TSUNAMI WARNING CENTER HONOLULU HI
1905 UTC THU SEP 18 2025
...PTWC TSUNAMI THREAT MESSAGE...
**** NOTICE **** NOTICE **** NOTICE **** NOTICE **** NOTICE *****
THIS MESSAGE IS ISSUED FOR INFORMATION ONLY IN SUPPORT OF THE
UNESCO/IOC PACIFIC TSUNAMI WARNING AND MITIGATION SYSTEM AND IS
MEANT FOR NATIONAL AUTHORITIES IN EACH COUNTRY OF THAT SYSTEM.
NATIONAL AUTHORITIES WILL DETERMINE THE APPROPRIATE LEVEL OF
ALERT FOR EACH COUNTRY AND MAY ISSUE ADDITIONAL OR MORE REFINED
INFORMATION.
**** NOTICE **** NOTICE **** NOTICE **** NOTICE **** NOTICE *****
PRELIMINARY EARTHQUAKE PARAMETERS
---------------------------------
* MAGNITUDE 7.8
* ORIGIN TIME 1858 UTC SEP 18 2025
* COORDINATES 53.0 NORTH 160.8 EAST
* DEPTH 10 KM / 6 MILES
* LOCATION OFF THE EAST COAST OF KAMCHATKA RUSSIA
EVALUATION
----------
* AN EARTHQUAKE WITH A PRELIMINARY MAGNITUDE OF 7.8 OCCURRED
OFF THE EAST COAST OF KAMCHATKA, RUSSIA AT 1858 UTC ON
THURSDAY SEPTEMBER 18 2025.
* BASED ON THE PRELIMINARY EARTHQUAKE PARAMETERS... HAZARDOUS
TSUNAMI WAVES ARE POSSIBLE FOR COASTS LOCATED WITHIN 1000 KM
OF THE EARTHQUAKE EPICENTER.
TSUNAMI THREAT FORECAST
-----------------------
* HAZARDOUS TSUNAMI WAVES FROM THIS EARTHQUAKE ARE POSSIBLE
WITHIN 1000 KM OF THE EPICENTER ALONG THE COASTS OF
RUSSIA.
RECOMMENDED ACTIONS
-------------------
* GOVERNMENT AGENCIES RESPONSIBLE FOR THREATENED COASTAL AREAS
SHOULD TAKE ACTION TO INFORM AND INSTRUCT ANY COASTAL
POPULATIONS AT RISK IN ACCORDANCE WITH THEIR OWN
EVALUATION... PROCEDURES AND THE LEVEL OF THREAT.
* PERSONS LOCATED IN THREATENED COASTAL AREAS SHOULD STAY ALERT
FOR INFORMATION AND FOLLOW INSTRUCTIONS FROM NATIONAL AND
LOCAL AUTHORITIES.
ESTIMATED TIMES OF ARRIVAL
--------------------------
* ESTIMATED TIMES OF ARRIVAL -ETA- OF THE INITIAL TSUNAMI WAVE
FOR PLACES WITH A POTENTIAL TSUNAMI THREAT. ACTUAL ARRIVAL
TIMES MAY DIFFER AND THE INITIAL WAVE MAY NOT BE THE
LARGEST. A TSUNAMI IS A SERIES OF WAVES AND THE TIME BETWEEN
WAVES CAN BE FIVE MINUTES TO ONE HOUR.
LOCATION REGION COORDINATES ETA(UTC)
------------------------------------------------------------
PETROPAVLOVSK RUSSIA 53.2N 159.6E 1937 09/18
UST KAMCHATSK RUSSIA 56.1N 162.6E 1940 09/18
MEDNNY ISLAND RUSSIA 54.7N 167.4E 1955 09/18
OSTROV KARAGINS RUSSIA 58.8N 164.5E 2008 09/18
SEVERO KURILSK RUSSIA 50.8N 156.1E 2050 09/18
UST KAHYRYUZOVO RUSSIA 57.1N 156.7E 0043 09/19
POTENTIAL IMPACTS
-----------------
* A TSUNAMI IS A SERIES OF WAVES. THE TIME BETWEEN WAVE CRESTS
CAN VARY FROM 5 MINUTES TO AN HOUR. THE HAZARD MAY PERSIST
FOR MANY HOURS OR LONGER AFTER THE INITIAL WAVE.
* IMPACTS CAN VARY SIGNIFICANTLY FROM ONE SECTION OF COAST TO
THE NEXT DUE TO LOCAL BATHYMETRY AND THE SHAPE AND ELEVATION
OF THE SHORELINE.
* IMPACTS CAN ALSO VARY DEPENDING UPON THE STATE OF THE TIDE AT
THE TIME OF THE MAXIMUM TSUNAMI WAVES.
* PERSONS CAUGHT IN THE WATER OF A TSUNAMI MAY DROWN... BE
CRUSHED BY DEBRIS IN THE WATER... OR BE SWEPT OUT TO SEA.
NEXT UPDATE AND ADDITIONAL INFORMATION
--------------------------------------
* THE NEXT MESSAGE WILL BE ISSUED IN ONE HOUR... OR SOONER IF
THE SITUATION WARRANTS.
* AUTHORITATIVE INFORMATION ABOUT THE EARTHQUAKE FROM THE U.S.
GEOLOGICAL SURVEY CAN BE FOUND ON THE INTERNET AT
EARTHQUAKE.USGS.GOV.
* FURTHER INFORMATION ABOUT THIS EVENT MAY BE FOUND AT
WWW.TSUNAMI.GOV.
* COASTAL REGIONS OF HAWAII... AMERICAN SAMOA... GUAM... AND
CNMI SHOULD REFER TO PACIFIC TSUNAMI WARNING CENTER MESSAGES
SPECIFICALLY FOR THOSE PLACES THAT CAN BE FOUND AT
WWW.TSUNAMI.GOV.
* COASTAL REGIONS OF CALIFORNIA... OREGON... WASHINGTON...
BRITISH COLUMBIA AND ALASKA SHOULD ONLY REFER TO U.S.
NATIONAL TSUNAMI WARNING CENTER MESSAGES THAT CAN BE FOUND
AT WWW.TSUNAMI.GOV.
$$
UPDATE 4:37 PM EDT
The National Tsunami Warning Center has updated its projections of a Tsunami after the
Magnitude 7.8 earthquake off Russia and now HAWAII is being Warned
TSUNAMI THREAT FORECAST...UPDATED
---------------------------------
* TSUNAMI WAVES REACHING 1 TO 3 METERS ABOVE THE TIDE LEVEL ARE
POSSIBLE ALONG SOME COASTS OF
RUSSIA.
* ACTUAL AMPLITUDES AT THE COAST MAY VARY FROM FORECAST
AMPLITUDES DUE TO UNCERTAINTIES IN THE FORECAST AND LOCAL
FEATURES. IN PARTICULAR MAXIMUM TSUNAMI AMPLITUDES ON ATOLLS
AND AT LOCATIONS WITH FRINGING OR BARRIER REEFS WILL LIKELY
BE MUCH SMALLER THAN THE FORECAST INDICATES.
* FOR OTHER AREAS COVERED BY THIS PRODUCT A FORECAST HAS NOT
YET BEEN COMPUTED. THE FORECAST WILL BE EXPANDED IF
NECESSARY IN SUBSEQUENT PRODUCTS.
RECOMMENDED ACTIONS
-------------------
* GOVERNMENT AGENCIES RESPONSIBLE FOR THREATENED COASTAL AREAS
SHOULD TAKE ACTION TO INFORM AND INSTRUCT ANY COASTAL
POPULATIONS AT RISK IN ACCORDANCE WITH THEIR OWN
EVALUATION... PROCEDURES AND THE LEVEL OF THREAT.
* PERSONS LOCATED IN THREATENED COASTAL AREAS SHOULD STAY ALERT
FOR INFORMATION AND FOLLOW INSTRUCTIONS FROM NATIONAL AND
LOCAL AUTHORITIES.
ESTIMATED TIMES OF ARRIVAL
--------------------------
* ESTIMATED TIMES OF ARRIVAL -ETA- OF THE INITIAL TSUNAMI WAVE
FOR PLACES WITHIN THREATENED REGIONS ARE GIVEN BELOW. ACTUAL
ARRIVAL TIMES MAY DIFFER AND THE INITIAL WAVE MAY NOT BE THE
LARGEST. A TSUNAMI IS A SERIES OF WAVES AND THE TIME BETWEEN
WAVES CAN BE FIVE MINUTES TO ONE HOUR.
LOCATION REGION COORDINATES ETA(UTC)
------------------------------------------------------------
PETROPAVLOVSK RUSSIA 53.2N 159.6E 1930 09/18
UST KAMCHATSK RUSSIA 56.1N 162.6E 1938 09/18
MEDNNY ISLAND RUSSIA 54.7N 167.4E 2002 09/18
OSTROV KARAGINS RUSSIA 58.8N 164.5E 2006 09/18
NAWILIWILI HAWAII 22.0N 159.4W 0051 09/19
HONOLULU HAWAII 21.3N 157.9W 0105 09/19
KAHULUI HAWAII 20.9N 156.5W 0111 09/19
HILO HAWAII 19.7N 155.1W 0129 09/19
