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Washington, South Washington Coast

Areal Flood Watch, High Surf Advisory

Statement as of 10:54 AM PST on December 19, 2014

Expires 7:00 PM EST on December 20, 2014


... Flood Watch in effect from Saturday afternoon through Monday
afternoon for southwest Washington and northwest Oregon...

The National Weather Service in Portland has issued a Flood Watch
for southwest Washington and northwest Oregon. This watch is in
effect from Saturday afternoon through Monday afternoon.

Confidence continues to increase that a classic atmospheric river
type precipitation event will set up over the Pacific northwest
over the weekend and continue into early Monday. A deep and moist
westerly flow is expected to develop Saturday morning and
strengthen later Saturday and Sunday. A very long fetch of
moisture with origins west to the South China Sea will feed into
this system... bringing the potential for very large rainfall
totals across the region. With the flow forecasted to remain
perpendicular to the Coast Range and Cascades for an extended
period of time... expect strong orographic enhancement to lead to
the highest rainfall totals over the mountains. The Coast
Range... foothills and Cascades are expected to see in the range of
6 to 12 inches of rain... with locally higher amounts possible.
Lower but still significant totals are expected for the lower
terrain. Projected rainfall along the coast is forecasted to be
around 4 to 8 inches... with 2 to 5 inches expected over the
interior lowlands.

Given the latest forecasted rainfall totals... it appears that
there is the strong potential for flooding over the weekend on
numerous rivers and tributaries draining the Coast Range and
Cascades. A few rivers may reach major flood stage. The Current
River stage forecasts indicate that the faster responding rivers
could reach flood stage as early as Saturday evening. There also
appears to be potential for flooding on some of the main Stem
rivers early next week. In addition to flooding potential on the
main Stem rivers and tributaries... there are likely to be impacts
from Urban and Small Stream flooding and flooding along low lying
pasture land.

In addition to the flooding concerns... excessive rainfall has the
potential to create landslides... debris flows... and excessive runoff
in the vicinity of recent wildfire burn scars. Burn scars from two
large fires this Summer... the 36 pit fire in the Clackamas river
basin near Estacada and the deception complex near Oakridge... will
be particularly vulnerable.

Precautionary/preparedness actions...

A Flood Watch means there is a potential for flooding based on
current forecasts.

Landslides and debris flows are possible during this flood event.
People... structures and roads located below steep slopes... in
canyons and near the mouths of canyons may be at serious risk
from rapidly moving landslides.

You should monitor later forecasts and be alert for possible
flood warnings. Those living in areas prone to flooding should be
prepared to take action should flooding develop.

The next update for this watch will be issued by 6 am Saturday
morning.




828 am PST Fri Dec 19 2014

... High surf advisory remains in effect until 4 PM PST Saturday...

A high surf advisory remains in effect until 4 PM PST Saturday.


* Seas and surf: seas will build rapidly this afternoon...
reaching 20 to 22 ft by this evening. Seas will remain around
20 ft through most of Saturday... falling below 20 ft by Saturday
evening.

* Highest concern: sneaker waves and beach erosion this afternoon
and tonight.

* Impacts: exercise extreme caution along beaches... especially
this afternoon. Unpredictable waves may Surprise Beach goers and
wash much farther up the beach than the preceding waves over the
previous 15 to 30 minutes. Please avoid area jetties through
Saturday.


Precautionary/preparedness actions...

A high surf advisory means that high surf will affect beaches in
the advisory area... producing rip currents and localized beach
erosion.




Http://www.Weather.Gov/Portland


Special Statement

Statement as of 3:37 PM PST on December 18, 2014

Expires 6:00 PM EST on December 19, 2014


... Flooding threat increasing Saturday night through Monday for
northwest Oregon and southwest Washington rivers...

Strong and deep moist westerly flow will begin crossing the pacnw
coast Saturday morning. A very long fetch of moisture is stretching
across the Pacific with origins west to the South China Sea and has
above average potential to bring heavy rains to the area. As
such... this continues to give the appearance of a classic high
precipitation atmospheric river event where the deep moist flow will
spend a significant amount of time on a nearly perpendicular course
against the Coast Range with the Cascades taking a bit higher of the
impact. Latest forecasts for Friday night through Monday afternoon
bring 8 to 12 inches of rain to the Cascades and foothills... 7 to
11 inches for the Coast Range... 5 to 7 inches along the immediate
coast... and 3 to 4 inches along the I-5 corridor.

Given latest data... it appears multiple Coast Range rivers have a
moderate potential of exceeding flood stage. Additionally... this
event has sufficient depth to bring significant rains to the north
Oregon and South Washington Cascades where rivers will also see
potential for notable flooding.

Keep in mind that details will always be in flux under these
scenarios as subtle north or south shifts cold make dramatic
differences in which basins receive extended periods of moderate to
heavy rain. Please continue to follow the latest forecasts and
impacts as conditions warrant.

Stay up to date with the latest NWS forecasts at
weather.Gov/Portland or Mobile.Weather.Gov

River forecasts are available on our web Page at
http://water.Weather.Gov/ahps2/index.Php?Wfo=pqr (all lower case)


Weather Severe Map
Arkansas - Record Report
California - High Surf Advisory , High Surf Advisory, Coastal Flood Advisory , Wind Advisory , Winter Weather Advisory , Beach Hazard Statement , Public Information Statement
Colorado - Winter Storm Watch , Public Information Statement
Florida - Public Information Statement
Georgia - Public Information Statement
Guam - High Surf Advisory
Idaho - Winter Storm Watch , Winter Weather Advisory , Public Information Statement
Kansas - Public Information Statement
Louisiana - Flood Watch , Record Report , Public Information Statement
Maine - Record Report
Mississippi - Record Report , Public Information Statement
Montana - High Wind Watch , High Wind Warning , Winter Storm Watch , Winter Weather Advisory , Winter Weather Statement
Nevada - Winter Weather Advisory
New Mexico - Public Information Statement
North Carolina - Special Statement
North Dakota - Dense Fog Advisory
Oregon - High Surf Advisory, Areal Flood Watch , High Surf Advisory, Areal Flood Watch , Areal Flood Watch , Areal Flood Watch, High Surf Advisory , Wind Advisory , Special Statement
Tennessee - Special Statement
Texas - Record Report , Public Information Statement
Utah - Winter Storm Watch , Public Information Statement
Virginia - Special Statement
Washington - Coastal Flood Advisory, High Surf Advisory, Areal Flood Watch , Areal Flood Watch , Areal Flood Watch, High Surf Advisory , High Wind Watch , Winter Weather Advisory , Special Statement , Record Report
Wyoming - High Wind Watch , Winter Storm Watch , Dense Fog Advisory , Special Statement
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