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fxus66 kotx 151236 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
436 am PST Fri Nov 15 2019

Synopsis...
a frontal system will bring rain and high elevation snow to the
Pacific northwest today. The chance for light rain will
persist through the weekend and into early next week. Snow levels
are expected to remain above the majority of our mountain passes
through early next week. Cooler temperatures and drier weather
will likely return by the middle of next week.



&&

Discussion...

Today: a frontal system will March across central and eastern
Washington this morning bringing a band of rain along with it. By
early to mid afternoon, frontal precipitation will be spreading
into the Idaho Panhandle. Places like Wenatchee, Omak, Grand
Coulee, and Moses Lake will likely receive less than a tenth of an
inch of rain this morning. Further east, the affects of the rain
shadow will be less pronounced. Colville, Spokane, and Pullman
will have a good shot of a tenth of an inch of rain. Many spots in
the north and central Idaho Panhandle may get close to a quarter
inch. Snow levels are expected to be in the 4000-5000ft range for
the mountains of northern Washington and the far north Idaho
Panhandle. At this time, it looks like rain or a rain/snow mix
for Lookout Pass at 4700ft on I-90.

Tonight: there won't be much wind following the passage of our
rainy frontal system this afternoon and evening. Without wind, low
clouds and fog will be common especially over the Idaho Panhandle
and the valleys of northeast Washington. The West Plains and
portions of the Palouse will likely experience fog and low clouds
as well with light southwesterly upslope winds through the night.

Saturday: the polar jet will retreat into central and southern
British Columbia on Saturday where moderate to locally heavy rain
will fall north of the Canadian border. Bands of light rain are
expected to spread across the northern Cascades and the
mountainous terrain of northeast Washington and the north Idaho
Panhandle during the afternoon into the overnight hours. The
majority of the inland northwest should be cloudy Saturday.
Afternoon temperatures in the 40s will be common with a few spots
in southeast Washington into the Clearwater valley of Idaho
possibly reaching the low 50s. /Gkoch

Sunday through Tuesday night: models show a brief atmospheric
river sagging south over the area Sunday morning bringing rain
to the Cascades and Idaho Panhandle. Mid level westerly flow is
expected to result in a rain shadow over much of central
Washington with a chance of rain over the eastern third of
Washington. Latest models show a weak short wave ridge nosing in
Sunday night into Monday. This should result in dry conditions
although areas of low clouds and fog is likely with models
indicating a continued moist boundary layer. Then there is good
agreement with the 00z models of an occluded front swinging
through the area Monday night into Tuesday bringing a good chance
of widespread precipitation. Although the air mass remains mild
with snow mainly above 5000 feet. Cooler and drier air begins to
move in Tuesday night as northerly flow develops. Jw

Wednesday and thursday: the remainder of any precipitation should
be out of the region by early Wednesday morning. The latter half
of the week will be dry and cooler with high temperatures back
into seasonal normals. High temperatures will be in the 30s and
40s, but most lows will drop below freezing into the 20s and lower
30s. Wednesday will be breezy with models showing a tight
pressure gradient through mostly the Columbia Basin and northern
valleys. However, low confidence due to plenty of time for things
to change. Js

&&

Aviation...
12z tafs: a frontal system will spread rain across central and
eastern Washington this morning and push into the Idaho Panhandle
during the afternoon. The prefrontal winds out of the south have
advected fog from southeast Washington into Spokane. Visibility of
a half mile or less will likely be the prevailing condition at
kgeg through mid morning. There is the potential for improvement
as the front brings a slight increase in wind as well as a bit of
mixing with falling precipitation. Chances are good that low
clouds will persist through the evening into Saturday morning
around Spokane and Coeur D'Alene with light upslope flow following
precipitation today. /Gkoch

&&

Preliminary point temps/pops...
Spokane 43 34 43 39 50 39 / 80 0 10 10 20 0
Coeur D'Alene 43 36 44 39 50 40 / 90 30 10 20 50 0
Pullman 47 37 48 41 55 42 / 80 20 0 0 20 10
Lewiston 50 39 52 43 58 43 / 80 20 0 0 20 10
Colville 43 32 43 37 52 34 / 90 0 30 30 20 0
Sandpoint 41 35 43 38 47 37 / 100 50 20 40 70 10
Kellogg 47 37 43 39 48 40 / 90 80 10 20 70 20
Moses Lake 46 31 47 38 57 36 / 50 0 10 0 10 0
Wenatchee 47 36 48 38 55 41 / 60 0 10 10 30 0
Omak 44 32 43 37 52 36 / 30 0 20 10 30 0

&&

Otx watches/warnings/advisories...
Idaho...none.

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