A tsunami warning has been issued for Pacific Islands including Hawaii following the 8.9 magnitude earthquake which occurred at 05:46 UTC on Friday 11th March in Japan. The first of a series of tsunami waves are expected to reach Hawaii at 03:07am HST on Friday 11th March 2011.
Hawaii Tsunami Warning – Courtesy Pacific Tsunami Warning Center
Tsunami Message Number 6
12:31am HST Friday March 11th 2011
To – Civil Defense in the State of Hawaii
Subject – Tsunami Warning Supplement
A tsunami warning continues in effect for the state of Hawaii.
An earthquake has occurred with these preliminary parameters.
Origin time – 07:46pm HST 10th March 2011
Co-ordinates – 38.3 North 142.4 East
Location – near East coast of Honshu, Japan
Magnitude – 8.9 Moment
Measurements or reports of Tsunami Wave Activity
GAUGE LOCATION LAT LON TIME AMPL PER
——————- —– —— —– ————— —–
DART 21415 50.2N 171.8E 0845Z 0.27M / 0.9FT 52MIN
WAKE US 19.3N 166.6E 0928Z 0.39M / 1.3FT 14MIN
NAHA OKINAWA JP 26.2N 127.7E 0901Z 0.25M / 0.8FT 60MIN
SAIPAN US 15.2N 145.7E 0916Z 0.65M / 2.1FT 30MIN
TOSASHIMIZU SHIKOKU 32.8N 133.0E 0753Z 0.92M / 3.0FT 68MIN
OMAEZAKI HONSHU JP 34.6N 138.2E 0818Z 1.42M / 4.6FT 56MIN
DART 21419 44.5N 155.7E 0716Z 0.40M / 1.3FT 20MIN
DART 21413 30.5N 152.1E 0659Z 0.76M / 2.5FT 32MIN
HANASAKI HOKKAIDO J 43.3N 145.6E 0657Z 2.79M / 9.2FT 76MIN
DART 21401 42.6N 152.6E 0643Z 0.67M / 2.2FT 40MIN
DART 21418 38.7N 148.7E 0619Z 1.08M / 3.5FT 06MIN
LAT – LATITUDE (N-NORTH, S-SOUTH)
LON – LONGITUDE (E-EAST, W-WEST)
TIME – TIME OF THE MEASUREMENT (Z IS UTC IS GREENWICH TIME)
AMPL – TSUNAMI AMPLITUDE MEASURED RELATIVE TO NORMAL SEA LEVEL.
IT IS …NOT… CREST-TO-TROUGH WAVE HEIGHT.
VALUES ARE GIVEN IN BOTH METERS(M) AND FEET(FT).
PER – PERIOD OF TIME IN MINUTES(MIN) FROM ONE WAVE TO THE NEXT.
NOTE – DART MEASUREMENTS ARE FROM THE DEEP OCEAN AND THEY
ARE GENERALLY MUCH SMALLER THAN WOULD BE COASTAL
MEASUREMENTS AT SIMILAR LOCATIONS.
A tsunami has been generated that could cause damage along coastlines of all islands in the state of Hawaii. Urgent action should be taken to protect lives and property.
A tsunami is a series of long ocean waves. Each individual wave crest can last 5 – 15 minutes or more and extensively flood coastal areas. The danger can continue for many hours after the initial wave as subsequent waves arrive. Tsunami wave heights cannot be predicted and the first wave may not be the largest.
Tsunami waves efficiently wrap around islands. All shores are at risk no matter which direction they face. The trough of a tsunami wave may temporarily expose the seafloor but the area will quickly flood again. Extremely strong and unusual nearshore currents can accompany a tsunami. Debris picked up and carried by a tsunami amplifies its destructive power. Simultaneous high tides or high surf can significantly increase the tsunami hazard.
THE ESTIMATED ARRIVAL TIME IN HAWAII OF THE FIRST TSUNAMI WAVE IS
0307 AM HST FRI 11 MAR 2011