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Area forecast discussion 
National Weather Service Spokane Washington
938 PM PST sun Dec 28 2014

Synopsis...
generally light snow showers will continue tonight and into early
Monday morning. Bitterly cold northeast winds will develop Monday
morning and continue into Monday night. Temperatures will be well
below average with dry conditions most of next week as Arctic high
pressure settles over the inland northwest.




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Discussion...
evening update: an inverted trof axis in the lower to mid levels
remains stretched from the Camas Prairie to Methow Valley this
evening. Meanwhile, a rather unstable atmosphere resides aloft and
this combination is bringing widely scattered snow showers
impacting just about every location at one time or another. Snow
amounts with this activity have generally been around an inch or
less but will lead to quick burst of snow covered roads. As of
830pm...the only void was directly over the Palouse into the
eastern Columbia Basin but these areas are dealing with another
travel hazard in the form of dense fog. Once snow showers
reorganize in these locations, fog should dissipate...otherwise,
the drier NE winds will definitely scrub this out by Monday
morning.

The well anticipated Arctic front is slowly sliding in from the
northeast and northeast winds are now blowing at Sandpoint and
cd'a 15-20 mph with gusts to 30 mph. This is just the beginning
and expect these winds to continue to strengthen into Monday as
The Heart of the cold air arrives. One change of note for early
Monday is the potential for strong winds to develop over the Lower
Basin generally over Adams, extreme western Whitman, lower
Lincoln, and southwestern Spokane counties. Incoming guidance
suggest winds for locations like Ritzville will be sustained
20-28 mph with gusts up to 40 mph.




&&

Aviation...
06z tafs: a stalled frontal boundary coupled with an unstable
atmosphere will bring scattered snow showers to all terminals
through 08z then decreasing from northeast to southwest as drier
Arctic air bleeds into the region. Winds will be quite gusty as
the Arctic air bleeds in with the strongest winds expected to
channel down the Purcell Trench and Okanogan Valley impacting
locations like Sandpoint, Coeur D Alene, Omak. The dense air mass
will also accelerate through the lower Columbia Basin bringing
sustained winds of 20-30 mph through Moses Lake and Ritzville.
Winds will be the main aviation concern by Monday afternoon then
weaken considerably Monday night as VFR skies return. /Sb




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Preliminary point temps/pops...
Spokane 18 21 5 12 1 14 / 50 10 0 0 0 0
Coeur D'Alene 17 20 1 12 1 14 / 60 10 0 0 0 0
Pullman 19 23 2 11 -2 14 / 50 30 10 0 0 0
Lewiston 24 29 7 15 4 17 / 60 50 10 0 0 0
Colville 20 24 2 17 0 19 / 60 10 0 0 0 0
Sandpoint 18 20 0 12 -1 14 / 50 10 10 0 0 0
Kellogg 15 17 -4 8 -3 16 / 60 10 10 0 0 0
Moses Lake 23 29 11 20 4 17 / 50 20 10 0 0 0
Wenatchee 25 30 12 21 10 21 / 70 60 10 0 0 0
Omak 21 26 6 15 3 16 / 60 20 0 0 0 0

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Otx watches/warnings/advisories...
Idaho...Wind Advisory from 8 am to 10 PM PST Monday for Coeur D'Alene
area-northern Panhandle.

Washington...Wind Advisory from 10 am to 10 PM PST Monday for Okanogan Valley.

&&

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