TSUNAMI INFORMATION STATEMENT NUMBER 3
NWS PACIFIC TSUNAMI WARNING CENTER EWA BEACH HI
0016 UTC TUE OCT 20 2020
..PTWC TSUNAMI SUPPLEMENT STATEMENT...
**** NOTICE **** NOTICE **** NOTICE **** NOTICE **** NOTICE *****
THIS STATEMENT 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 *****
THE TSUNAMI FORECAST IS UNCHANGED IN THIS MESSAGE.
PRELIMINARY EARTHQUAKE PARAMETERS
---------------------------------
* MAGNITUDE 7.5
* ORIGIN TIME 2055 UTC OCT 19 2020
* COORDINATES 54.7 NORTH 159.6 WEST
* DEPTH 41 KM / 25 MILES
* LOCATION SOUTH OF ALASKA
EVALUATION
----------
* AN EARTHQUAKE WITH A PRELIMINARY MAGNITUDE OF 7.5 OCCURRED
SOUTH OF ALASKA AT 2055 UTC ON MONDAY OCTOBER 19 2020.
* ADDITIONAL TSUNAMI OBSERVATIONS HAVE BEEN MADE.
RECOMMENDED ACTIONS
-------------------
* FOR COASTAL AREAS IMPACTED BY TSUNAMI WAVES... CAREFULLY
MONITOR FOR ANY CONTINUING SEA LEVEL CHANGES. WHEN HAZARDOUS
WAVES HAVE NOT BEEN OBSERVED FOR AT LEAST TWO HOURS THEN IT
CAN BE ASSUMED THE HAZARD HAS PASSED. HOWEVER... CONTINUE TO
EXERCISE CAUTION AROUND THE SEA AS SMALLER TSUNAMI
FLUCTUATIONS MAY CONTINUE FOR MANY MORE HOURS.
* FOR OTHER COASTAL AREAS... IF HAZARDOUS WAVES HAVE NOT BEEN
OBSERVED FOR AT LEAST TWO HOURS AFTER THE ESTIMATED ARRIVAL
TIME THEN IT CAN BE ASSUMED THE HAZARD HAS PASSED.
HOWEVER... SMALL SEA LEVEL FLUCTUATIONS MAY OCCUR AND NORMAL
CAUTION AROUND THE SEA SHOULD BE EXERCISED.
POTENTIAL IMPACTS
-----------------
TSUNAMI OBSERVATIONS
--------------------
* THE FOLLOWING ARE TSUNAMI WAVE OBSERVATIONS FROM COASTAL
AND/OR DEEP-OCEAN SEA LEVEL GAUGES AT THE INDICATED
LOCATIONS. THE MAXIMUM TSUNAMI HEIGHT IS MEASURED WITH
RESPECT TO THE NORMAL TIDE LEVEL.
GAUGE TIME OF MAXIMUM WAVE
COORDINATES MEASURE TSUNAMI PERIOD
GAUGE LOCATION LAT LON (UTC) HEIGHT (MIN)
-------------------------------------------------------------
CHIGNIK AK 56.3N 158.4W 2320 0.68M/ 2.2FT 20
DART 46402 51.0N 164.1W 2134 0.04M/ 0.1FT 16
SAND POINT AK 55.3N 160.5W 2301 0.67M/ 2.2FT 22
KING COVE AK 55.1N 162.3W 2302 0.68M/ 2.2FT 16
DUTCH HBR UNALASKA 53.9N 166.5W 2259 0.07M/ 0.2FT 26
NEXT UPDATE AND ADDITIONAL INFORMATION
--------------------------------------
* THIS WILL BE THE FINAL STATEMENT ISSUED FOR THIS EVENT UNLESS
NEW INFORMATION IS RECEIVED OR THE SITUATION CHANGES.
* 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.
$$
