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Area forecast discussion 
National Weather Service Spokane Washington
1030 am PST sun Dec 21 2014

Synopsis...
the active weather from the past few days will begin to wind down
today and Monday. Expect warm temperatures and very gusty winds
this afternoon. A storm system will move down from the north and impact
the region around Christmas eve. This will bring the potential
for moderate to heavy snow in the mountains and light
accumulations to the valleys. Temperatures are expected to remain
above average through early next week...before dropping down
toward normal values by Christmas day. Another winter storm may
affect the region for next weekend.

&&

Discussion...
rest of today...the heavy rain generating Pacific moisture feed
has slumped south of the region this morning...leaving the
forecast area under a fast but still moist zonal regime. This is
creating a good rain shadow over the basin...but some slop-over
rain and mountain snow showers will continue over the Cascades
with some of these showers making it out into the western basin
before the downslope effect crushes them. Also residual showers
will persist over the far southeastern zones into the afternoon
with the l-c valley laying close to the fringe of the deepest
moisture.

Otherwise the wind will be the dominant issue for the rest of the
day. The surface gradient is not terribly impressive...strong
enough to support 20 to 30 mph winds on exposed locations but gust
potential in the mixing layer may allow some 40 to 35 mph gusts to
surface onto the Palouse area and the high terrain of Garfield
County. The Wind Advisory for the eastern Columbia Basin will
continue through 4 PM and probably be allowed to expire. Snow over
the Shoshone County mountains has tapered off north of Interstate
90 but snow showers will continue south of I-90 through the
afternoon. /Fugazzi

&&

Aviation...
18z tafs: overall a fast westerly flow will dominate the region
for the next 24 hours. This will create dense upslope showers of
rain and snow mainly over the Cascade crest with some of these showers
reaching the keat taf site between 18z and 00z. Otherwise the
klws taf site will have the best chance of occasional showers this
afternoon. All other taf sites will be generally dry but with
breezy and gusty southwest winds. VFR conditions are expected to
prevail at all taf sites except a small chance of brief MVFR
conditions at keat this afternoon. Overnight tonight as winds die
down a moist boundary layer may promote IFR or low MVFR stratus
ceilings at the kgeg area taf sites. /Mjf

&&

Preliminary point temps/pops...
Spokane 48 31 39 30 40 34 / 10 10 10 10 30 40
Coeur D'Alene 46 31 39 28 39 34 / 10 20 20 10 30 60
Pullman 51 36 43 31 43 34 / 50 50 30 10 20 40
Lewiston 56 38 47 32 46 36 / 40 50 20 10 20 40
Colville 45 28 38 27 36 32 / 10 10 10 10 40 50
Sandpoint 43 30 37 26 36 33 / 10 20 10 10 40 60
Kellogg 42 31 37 27 36 33 / 60 90 40 10 50 60
Moses Lake 51 33 43 31 42 34 / 10 10 10 0 20 20
Wenatchee 47 34 42 32 39 33 / 40 20 10 10 30 20
Omak 41 28 36 28 35 31 / 10 10 10 0 40 40

&&

Otx watches/warnings/advisories...
Idaho...Wind Advisory until 4 PM PST this afternoon for Idaho Palouse-
Lewis and southern Nez Perce counties-Lewiston area.

Washington...Wind Advisory until 4 PM PST this afternoon for lower Garfield
and Asotin counties-northeast Blue Mountains-Spokane area-
upper Columbia Basin-Washington Palouse.

&&

$$

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