

Tsunami watch issued for SF bay area ~8am Friday - anigbrowl
http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/03/messagelhvpd9-03.htm

======
Bud
When you will be destroyed:

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

Who will be destroyed:

[http://www.socketsite.com/archives/2009/12/san_franciscos_ts...](http://www.socketsite.com/archives/2009/12/san_franciscos_tsunami_inundation_map_literally_not_fig.html)

~~~
ars
Interesting how Alaska manages to be both first and last on that list.

Mainly because of its long "tail" (stinger?).

~~~
uvdiv
Here is the map [1]. The Aleutian islands are hit first, but it seems the big
effect is the slowing-down of the wave in very shallow waters. (Here's depth
maps: [2][3]). Note the contours -- it takes ~9 hours for the tsunami to cross
this small sea (Bering), the same time as it takes to cross the entire Pacific
from Japan to British Columbia.

According to [4], shallow-water waves (including tsunamis) have speed
proportional to sqrt(depth). Not sure how accurate this approximation is, but
it seems to get the order-of-magnitude right.

This FAQ [5] says that much of the energy should be reflected off the
continental slope (where it goes from deep to shallow abruptly), so the
tsunamis there should be pretty small. The tsunami height-forecast [6] says
the same thing.

[1]
[http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/06/ttvulhvpd9-0...](http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/06/ttvulhvpd9-06.jpg)

[2]
[http://www.gebco.net/data_and_products/gebco_world_map/image...](http://www.gebco.net/data_and_products/gebco_world_map/images/gda_world_map_small.jpg)

[3]
[http://disc.sci.gsfc.nasa.gov/oceancolor/additional/science-...](http://disc.sci.gsfc.nasa.gov/oceancolor/additional/science-
focus/images/bering_sea_bathymetry.gif)

[4]
[http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16...](http://oceanworld.tamu.edu/resources/ocng_textbook/chapter16/chapter16_01.htm)

[5] <http://wcatwc.arh.noaa.gov/faq/ArcticTalkingPoints.htm>

[6]
[http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04...](http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04.jpg)

------
ars
Not just the bay area.

The readers of HN don't just live in CA you know.

It's the entire west coast of the US, Canada and Mexico, including Hawaii and
Alaska.

Actually it's the entire west coast of both North and South America and any
islands. Also Australia, New Zealand and Asia.

~~~
anigbrowl
Yes, sorry. I just popped it up as soon as I saw it, and focused on SF since I
live here.

------
macrael
San Francisco danger is now over. I'm on a Search and Rescue team that was
called up by the Sheriff's Office to be on call, but nothing notable happened
and everyone is going home.

------
anigbrowl
Wave energy maps
[http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04...](http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/energylhvpd9-04.jpg)

------
_delirium
The Santa Cruz newspaper claims it will be quite small in the bay area,
fortunately:

 _The warning covers coastal areas between Point Concepcion to the Oregon-
Washington border. While the warning does encourage people in low-lying areas
to move inland, officials don't expect the wave that hits the California Coast
to be much more than a foot._

edit: Though the NYTimes says
(<http://www.nytimes.com/2011/03/12/us/12california.html>):

 _Surges could reach three to seven feet along the California, Oregon and
Washington coasts. Southern California is expected to be hit by three-foot
waves, the authorities said._

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melvinram
According to the linked message, it's still a "watch" for the west coast
(including SF), which is "issued to areas which will not be immediately
impacted by the tsunami." I don't see where on the page it was upgraded. Can
someone point this out?

Update: The updated message is on this page:
[http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/04/messagelhvpd...](http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/04/messagelhvpd9-04.htm)

~~~
anigbrowl
Yeah, I couldn't update the URL properly. <http://wcatwc.arh.noaa.gov/> is the
latest at all times. I'm going to go to bed soon and get up early; I don't
anticipate danger here, but it's possible there will be some evacuation
downhill from me (94116).

------
Bud
At least according to the latest reports from NOAA, the warning/watch does not
apply to the US West Coast at this time:

[http://www.weather.gov/ptwc/text.php?id=hawaii.2011.03.11.08...](http://www.weather.gov/ptwc/text.php?id=hawaii.2011.03.11.083152)

A good general page to keep open tonight if you are following this story:

<http://www.weather.gov/ptwc/>

~~~
Bud
Apologies. It appears my above comment was incorrect:

<http://wcatwc.arh.noaa.gov/>

------
Bud
Definitely a warning. Here's the most current and clearest map I've seen:

[http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/05/wwareaslhvpd...](http://wcatwc.arh.noaa.gov/2011/03/11/lhvpd9/05/wwareaslhvpd9-05.gif)

------
anonymoushn
Saturday or Friday? According to the linked page it should begin arriving in
Alaska 2 minutes ago, but the list of "Estimated tsunami arrival times" seems
to be an empty file.

~~~
anigbrowl
Friday. Sorry, it's been a long day. I live on the west side of SF near the
ocean; danger unlikely at my elevation, but they're deploying police to keep
people away from the beach.

With luck, they're erring on the side of caution; low tide is about 10:30am,
so flooding seems unlikely...but this is such a rare event that it's a total
guess. Just keep an eye on the weather sites and hope news from Hawaii is not
too bad.

------
olivercameron
I live on Ocean Beach in San Francisco, and apparently there is nothing to
worry about, other than to stay off the beach. I'll keep you all posted if
things get crazy.

~~~
chopsueyar
Can you stream some live video with justin.tv?

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mkramlich
I've heard it will probably be fine in SF. That said, I'll be over here in
Denver.

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gonzo
not much happening here in Hawaii

