Tsunami message from WCATWC

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 #15 issued 03/11/2011 at 11:45AM PST

The advisory and warning regions have not changed. Tsunami observations are updated 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 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 Attu, Alaska.

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
 ------------------------  -----  ------  -------     -----------

 North Spit  CA            40.8N  124.2W  1630UTC   03.1FT/00.95M
 Port San Luis  CA         35.2N  120.8W  1721UTC   06.3FT/01.93M
 Port Angeles  WA          48.1N  123.4W  1827UTC   01.9FT/00.59M
 Winter Harbour  BC        50.7N  128.3W  1450UTC   01.7FT/00.53M
 Santa Monica  CA          34.0N  118.5W  1845UTC   02.4FT/00.74M
 Santa Barbara  CA         34.4N  119.7W  1801UTC   02.2FT/00.67M
 Sand Point  AK            55.3N  160.5W  1812UTC   01.6FT/00.49M
 Nikolski  AK              52.9N  168.9W  1614UTC   02.7FT/00.82M
 King Cove  AK             55.1N  162.3W  1713UTC   01.6FT/00.48M
 Craig  AK                 55.5N  133.1W  1613UTC   00.8FT/00.24M
 Elfin Cove  AK            58.2N  136.3W  1535UTC   00.5FT/00.16M
 Sitka  AK                 57.1N  135.3W  1711UTC   01.0FT/00.32M
 Point Reyes  CA           38.0N  123.0W  1803UTC   04.4FT/01.35M
 Port Orford  OR           42.7N  124.5W  1724UTC   06.1FT/01.85M
 Adak  AK                  51.9N  176.6W  1747UTC   03.4FT/01.05M
 Kodiak  AK                57.7N  152.5W  1550UTC   00.5FT/00.15M
 Los Angeles  CA           33.7N  118.3W  1905UTC   01.1FT/00.32M
 San Diego  CA             32.7N  117.2W  1906UTC   00.7FT/00.21M
 La Jolla  CA              32.9N  117.3W  1834UTC   01.0FT/00.31M

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).

THE TSUNAMI IMPACT CONTINUES ALONG THE WEST COAST. TSUNAMI AMPLITUDE IS STILL RISING AT SOME LOCATIONS AND IS EXPECTED TO PERSIST FOR SEVERAL MORE HOURS. PLEASE STAY TUNED TO INSTRUCTION FROM YOU LOCAL EMERGENCY OFFICIALS BEFORE RETURNING TO ENDANGERED AREAS. FURTHER WAVE OBSERVATIONS ARE POSTED 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.

Link to Standard Warning Message
Link to Public Warning Message
Link to XML/CAP Message
Link to Printable Message