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Area forecast discussion 
National Weather Service Spokane Washington
852 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...
00z tafs: a cold upper level trough and surface low pressure will
persist over the region through the next 24 hours. The eastern taf
sites including kgeg...kcoe...ksff and kpuw will be under threat
for IFR and LIFR conditions in snow through 02-03z as moist isentropic
ascent continues. Conditions will improve after 02z-03z as a dry
slot moves through the region...but deterioration will occur
after 06z with a cold front band of snow showers. Klws will
probably remain VFR through this evening but with snow or rain
showers nearby. Kmwh and keat will benefit from downslope off the
Cascades for primarily VFR conditions. On Sunday cold air aloft
will destabilize the air mass leading to scattered snow showers
over the eastern taf sites promoting occasional periods of low
MVFR or IFR conditions in snow. /Mjf







&&

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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