For more information, please see the latest bulletins at the West Coast & Alaska Tsunami Warning Center.
To: U.S. West Coast, Alaska, and British Columbia coastal regions From: NOAA/NWS/West Coast and Alaska Tsunami Warning Center Subject: Tsunami Warning and Advisory #8 issued 03/11/2011 at 4:43AM PST The warning and advisory areas remain the same. More observations are included below. The Tsunami Warning continues in effect for the coastal areas of California and Oregon from Point Concepcion, California to the Oregon-Washington border. The Tsunami Warning continues in effect for the coastal areas of Alaska from Amchitka Pass, Alaska (125 miles W of Adak) to Attu, Alaska. The Tsunami Advisory continues in effect for the coastal areas of California from the California-Mexico border to Point Concepcion, California. The Tsunami Advisory continues in effect for the coastal areas of Washington, British Columbia and Alaska from the Oregon- Washington border to Amchitka Pass, Alaska (125 miles W of Adak). A Tsunami Warning means that all coastal residents in the warning area who are near the beach or in low-lying regions should move immediately inland to higher ground and away from all harbors and inlets including those sheltered directly from the sea. Those feeling the earth shake, seeing unusual wave action, or the water level rising or receding may have only a few minutes before the tsunami arrival and should move immediately. Homes and small buildings are not designed to withstand tsunami impacts. Do not stay in these structures. All residents within the warned area should be alert for instructions broadcast from their local civil authorities. A tsunami has been recorded. A Tsunami Advisory means that a tsunami capable of producing strong currents or waves dangerous to persons in or very near the water is expected. Significant, widespread inundation is not expected for areas under an advisory. Currents may be hazardous to swimmers, boats, and coastal structures and may continue for several hours after the initial wave arrival. At 9:46 PM Pacific Standard Time on March 10, an earthquake with preliminary magnitude 8.9 occurred near the east coast of Honshu, Japan . (Refer to the United States Geological Survey for official earthquake parameters.) This earthquake has generated a tsunami which could cause damage to coastal regions in a warning or advisory. Estimated tsunami arrival times and maps along with safety rules and other information can be found on the WCATWC web site. Measurements or reports of tsunami activity: Location Lat. Lon. Time Amplitude ------------------------ ----- ------ ------- ----------- Shemya AK 52.7N 174.1E 1130UTC 05.1FT/01.56M Adak AK 51.9N 176.6W 1112UTC 01.5FT/00.46M Boso Japan 34.8N 140.8E 0600UTC 02.5FT/00.75M Naha Japan 26.2N 127.7E 1022UTC 01.6FT/00.49M Ofunato Japan 39.0N 141.8E 0603UTC 10.7FT/03.25M Omaezaki Japan 34.6N 138.2E 0809UTC 04.6FT/01.39M Tokai Japan 33.8N 137.6E 0649UTC 00.8FT/00.23M Tosashimizu Japan 32.8N 132.9E 0753UTC 03.0FT/00.91M Kwajalein Marshall Isl 8.7N 167.7E 1049UTC 01.0FT/00.30M Midway Is. USA 28.2N 177.4W 1044UTC 05.1FT/01.55M Wake Is. USA 19.3N 166.6E 0918UTC 01.7FT/00.52M Legaspi Philippines 13.2N 123.8E 1020UTC 01.1FT/00.32M Dutch Harbor AK 53.9N 166.5W 1134UTC 01.6FT/00.48M Nikolski AK 52.9N 168.9W 1156UTC 01.4FT/00.41M French Frigate Shoals 23.5N 166.2W 1211UTC 01.5FT/00.45M St Paul Is. AK 57.1N 170.3W 1225UTC 02.0FT/00.61M Time - Time of measurement. Amp. - Tsunami amplitudes are measured relative to normal sea level. It is NOT crest-to-trough wave height. Values are given in both meters (M) and feet (FT). TSUNAMI AMPLITUDES ARE EXPECTED TO PEAK TWO TO THREE HOURS AFTER INITIAL ARRIVAL ALONG THE NORTH AMERICAN COAST. FORECAST TSUNAMI AMPLITUDES ARE AVAILABLE ON THE WCATWC WEB SITE WCATWC.ARH.NOAA.GOV. Tsunamis can be dangerous waves that are not survivable. Wave heights are amplified by irregular shoreline and are difficult to forecast. Tsunamis often appear as a strong surge and may be preceded by a receding water level. Mariners in water deeper than 600 feet should not be affected by a tsunami. Wave heights will increase rapidly as water shallows. Tsunamis are a series of ocean waves which can be dangerous for several hours after the initial wave arrival. DO NOT return to evacuated areas until an all clear is given by local civil authorities. 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. This message will be updated in 60 minutes or sooner if the situation warrants. The tsunami message will remain in effect until further notice. For further information stay tuned to NOAA Weather Radio, your local TV or radio stations, or see the WCATWC web site.