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Area forecast discussion 
National Weather Service Spokane Washington
955 PM PST Sat Dec 27 2014

Synopsis...
scattered snow showers will continue overnight into Sunday with
light to moderate accumulations in the Idaho Panhandle...Cascade
crest...and portions of eastern Washington. Bitterly cold
northeast winds will develop by Monday 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.

&&

Discussion...
steady snow has ended and the region is transitioning into an
unstable atmosphere. The most consistent snow shower activity will
be in the oropgraphically favored areas including the Idaho
mountains, Cascade crest, and blue mtns. However, there are at
least two vorticity maximums spinning in a line from ern Washington to
central British Columbia on the cyclonic side of the upper level jet. Each of
these will bring the potential for clusters of snow showers...some
which could bring quick bursts of 1-2 inches. Hrrr suggest far NE
Washington may encounter one of these waves now and another in a few hours
so opted to leave Winter Storm Warning going with wording of
localized accumulations. It is conceivable that these same
local accumulations hit the Okanogan Valley, Spokane area, or
Washington Palouse but given the low confidence and above freezing
temperatures from Spokane to Pullman, opted to cancel highlights.

&&

Aviation...
06z tafs: the region has transitioned to the cool and unstable
side of the polar jet and steady wdsprd pcpn has waned. The focus
now will be several smaller scale circulations evident via
satellite from southeast Washington to central British Columbia. These waves will dig south
through the region during the next 12-18 hours bringing clusters
of rain/snow showers eventually becoming all snow. Any
accumulations will be localized and carry low confidence. Moist
boundary layer conditions will deliver a low confidence
ceiling/vis fcst as well and fcst may be optimistic. A push of
cooler and drier air from Canada will arrive Sunday evening
swinging winds around to the NE and incr the chance for light snow
showers with the frontal passage. Accumulations with this feature
will be light and snow will be more light and fluffy compared to
the wet nature observed Saturday. /Sb





&&

Preliminary point temps/pops...
Spokane 27 31 18 21 5 14 / 80 30 20 10 0 0
Coeur D'Alene 27 31 17 20 3 14 / 100 50 20 10 0 0
Pullman 29 33 19 23 3 14 / 100 70 30 30 10 0
Lewiston 32 38 24 29 9 19 / 100 60 40 30 10 0
Colville 26 33 20 24 1 18 / 60 30 20 10 0 0
Sandpoint 27 32 18 20 2 15 / 100 40 20 10 10 0
Kellogg 26 30 15 17 -3 11 / 100 70 40 20 10 0
Moses Lake 27 33 23 29 8 22 / 20 20 50 30 0 0
Wenatchee 28 34 25 30 12 23 / 20 20 60 40 0 0
Omak 25 29 21 26 4 17 / 20 10 40 20 0 0

&&

Otx watches/warnings/advisories...
Idaho...Winter Storm Warning until 4 PM PST Sunday for central Panhandle
mountains-Lewis and southern Nez Perce counties.

Winter Storm Warning until 4 am PST Sunday for Coeur D'Alene
area-Idaho Palouse-northern Panhandle.

Washington...Winter Storm Warning until 4 PM PST Sunday for northeast Blue
Mountains.

Winter Storm Warning until 4 am PST Sunday for northeast
mountains.

Winter Weather Advisory until 4 am PST Sunday for east slopes
northern Cascades.

&&

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