West Coast - in danger from tsunami?

[Hugabear]

What's the word on the tsunami heading towards the West Coast?

[nadinbrzezinski]

1. Not yet, but keep an eye on it

To: U.S. West Coast, Alaska, and British Columbia coastal regions
From: NOAA/NWS/West Coast and Alaska Tsunami Warning Center
Subject: Tsunami Watch and Advisory #3 issued 03/10/2011 at 11:33PM PST

UPDATED MAGNITUDE TO 8.8

The Tsunami Advisory continues in effect for the coastal areas of Alaska from Chignik Bay, Alaska to Attu, Alaska.

The Tsunami Watch continues in effect for the coastal areas of California, Oregon, Washington, British Columbia and Alaska from the California-Mexico border to Chignik Bay, Alaska.

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.

A Tsunami Watch means that all coastal residents in the watch area should prepare for possible evacuation. A tsunami watch is issued to areas which will not be immediately impacted by the tsunami. Watch areas will either be upgraded to warning or advisory status, or canceled.

At 9:46 PM Pacific Standard Time on March 10, an earthquake with preliminary magnitude 8.8 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. The waves are expected to first reach Shemya, Alaska at 12:13 AM AKST on March 11. Estimated tsunami arrival times and maps along with safety rules and other information can be found on the WCATWC web site.

Measurements of reports of tsunami activity:
TSUNAMI OBSERVED ON DEEP OCEAN BUOY
UPGRADED MAGNITUDE TO 8.8

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 30 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

They will upgrade to warning IF the levels go up

[Abq_Sarah]

2. Coastline is under a watch

As of the last 30 minutes.

[aquart]

3. Just a watch. Edit. It's a warning now.

But I know people in Hawaii and I have no idea what they're doing.

[necso]

4. At 8.8, a very large earthquake;

and there is no blocking land mass on a line between the earthquake (tsunami source) and the west coast. (Although the bottom of the pacific ocean is not flat.)

But the strength of a tsunami typically falls off sharply with distance. However, shore topography can play an important role in local strength of effect.

I wouldn't be worried about 30 feet high waves.

[REP]

5. Yes. We're under a WARNING from Point Conception to the Oregon border

http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/01/webetalhvpd9-01.txt

[OneGrassRoot]

6. Please forgive my ignorance....

How do we interpret the estimated times given?

I know my EST is seven hours ahead of GMT, but I'm not sure how to read the estimated tsunami impact times.

:(

[REP]

8. There are no impact times, just estimated arrival times

Eaxmples:


the Alaska/British Columbia border 0538 PST MAR 11 1338 UTC MAR 11

5:38 Pacific Standard Time March 11 13:38 UTC

Valdez, Alaska 0443 AKST MAR 11 1343 UTC MAR 11

4:43 Alaska Standard Time March 11 1343 March 11


etc

[OneGrassRoot]

9. Yeah, sorry....once I looked more closely

I saw the PST and such times given.

At first it was just a jumble of military numbers to my tired eyes.

Thanks. :)

[pokerfan]

7. Latest bulletin

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 #5 issued 03/11/2011 at 1:45AM PST

THIS MESSAGE KEEPS THE ADVISORY AND WARNING AREAS THE SAME AND ADDS MORE TSUNAMI OBSERVATIONS.

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.

http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/05/messagelhvpd9-05.htm

[AsahinaKimi]

10. This is not good.