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To: U.S. West Coast, Alaska, and British Columbia coastal regions
From: NOAA/NWS/West Coast and Alaska Tsunami Warning Center
Subject: Tsunami Information Statement #1 issued 03/10/2011 at 9:58PM PST

This is a Tsunami Information Statement for California, Oregon, Washington, British Columbia, and Alaska. NO tsunami warning, watch or advisory is in effect for these areas.

Earthquakes of this size are known to generate tsunamis potentially dangerouse to coasts outside the source region. The West Coast/Alaska Tsunami Warning Center is investigating the event to determine the level of danger. More information will be issued as it becomes available.

At 9:46 PM Pacific Standard Time on March 10, an earthquake with preliminary magnitude 7.9 occurred near the east coast of Honshu, Japan . (Refer to the United States Geological Survey for official earthquake parameters.)

Pacific coastal regions outside California, Oregon, Washington, British Columbia, and Alaska should refer to the Pacific Tsunami Warning Center messages for information on the event.

Messages will be issued hourly by the WCATWC until the event status is upgraded to a warning or advisory, or until the center has determined that the event poses no threat to the California, Oregon, Washington, British Columbia, and Alaska coasts. See the WCATWC web site for basic tsunami information, safety rules, and a tsunami travel time map and table. (NOTE: Travel time maps and tables indicate forecasted times only, not that a wave dangerous to the U.S. and Canadian coasts was generated

NWS PACIFIC TSUNAMI WARNING CENTER EWA BEACH HI
844 PM HST THU MAR 10 2011
TO - CIVIL DEFENSE IN THE STATE OF HAWAII
SUBJECT - TSUNAMI WATCH SUPPLEMENT

A TSUNAMI WATCH CONTINUES IN EFFECT FOR THE STATE OF HAWAII.

AN EARTHQUAKE HAS OCCURRED WITH THESE PRELIMINARY PARAMETERS
ORIGIN TIME - 0746 PM HST 10 MAR 2011
COORDINATES - 38.2 NORTH 142.5 EAST
LOCATION - NEAR EAST COAST OF HONSHU JAPAN
MAGNITUDE - 8.8 MOMENT

MEASUREMENTS OR REPORTS OF TSUNAMI WAVE ACTIVITY
GAUGE LOCATION LAT LON TIME AMPL PER
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.

EVALUATION
BASED ON ALL AVAILABLE DATA A TSUNAMI MAY HAVE BEEN GENERATED BY
THIS EARTHQUAKE THAT COULD BE DESTRUCTIVE ON COASTAL AREAS EVEN
FAR FROM THE EPICENTER. AN INVESTIGATION IS UNDERWAY TO DETERMINE
IF THERE IS A TSUNAMI THREAT TO HAWAII.

IF TSUNAMI WAVES IMPACT HAWAII THE ESTIMATED EARLIEST ARRIVAL OF THE FIRST TSUNAMI WAVE IS 0259 AM HST FRI 11 MAR 2011