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fxus66 kotx 170050 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
450 PM PST Tue Jan 16 2018

Synopsis...
after a brief break, the next round of precipitation will reach
the Cascades by Wednesday and spread across the inland northwest
Wednesday night into Thursday. Anticipate a rain/snow mix in the
valleys with some significant snow in the mountains. A cooler and
showery conditions expected Friday into Saturday, followed by the
potential for more snow and rain by Sunday.

&&

Discussion...
tonight and wednesday: the remains of the weakened front will push
eastward this evening, leaving a moist airmass behind. Anticipate
clearing skies to continue across southeast Washington and the
southern Columbia Basin. Although with light winds, low clouds and
fog looks to linger into the evening across the northern Columbia
Basin, West Plains and some of the northern valleys, with
visibilities dropping to less than a mile at times. The weather
pattern will remain active as the next Pacific system nears. A
warm front should lift across the northern Cascades late tonight
into Wednesday morning which will bring a band of light
precipitation to north central Washington. The early arrival of
this feature looks to bring light snow to most locations, although
a light wintry mix of precipitation is possible in the Cascade
valleys to the Okanogan Valley by Wednesday morning as overnight
lows dip to around freezing. Cascade mountains will receive the
best chance of snow with 2 to 5 inches possible. The warm front
will lift to the Canadian border by afternoon with light valley
rain and mountain snow for the rest of the day. Wednesday
afternoon temperatures will warm a couple more degrees, topping
out in the mid 30s to upper 40s. /Rfox.

Wednesday night through tuesday: a large frontal zone, with
substantial moisture fluxing through it, makes a slow March east
across eastern Washington and into north Idaho Wednesday night
with an eventual exit of the front Thursday. The result will be a
wet one with generally snow in the mountains with a rain snow mix
or all rain in valleys and lowlands. Forecast temperatures are
likely to be the warmest of the seven day forecast and winds do
show some increase and a shift to southwest when the back edge of
the front passes Thursday. The airmass left behind is a cold and
conditionally unstable one allowing for a transition to a more
showery precipitation type with lower snow levels and cooler
temperatures lingering Thursday night on until Saturday. Yet
another winter storm system is progged to drag a wet frontal zone
through the area Saturday night/Sunday followed up with another
residence of cold conditionally unstable air. This system doesn't
appear as warm as the Wednesday night/Thursday one but will result
in some southerly flow and thus another nudge up in temperatures
more apparent in daytime highs. The remaining conditionally
unstable airmass left in its wake lingers Monday/Tuesday allowing
for yet another transition to a more showery precipitation type
with lower snow levels and cooler temperatures. /Pelatti

&&

Aviation...
00z tafs: the area will remain between waves tonight, before
another approaches from the west tomorrow. Low clouds and areas of
fog will linger around the Columbia Basin, with conditions varying
between VFR and IFR, with MVFR/IFR conditions more likely
overnight into early Wednesday. Areas toward lws/puw are more apt
to remain VFR with a southeast wind. The approach of the next wave
tomorrow will increase some precipitation chances from the west.
Much of the day that risk will be toward eat, but we will have to
watch for some approaching the east with the initial wave of
clouds. /J. Cote'

&&

Preliminary point temps/pops...
Spokane 31 39 37 41 30 37 / 10 10 100 90 40 20
Coeur D'Alene 30 39 36 40 31 36 / 10 10 100 90 50 30
Pullman 33 45 39 44 31 40 / 0 10 80 90 30 20
Lewiston 36 48 41 46 34 44 / 0 0 50 100 30 20
Colville 31 37 34 40 29 36 / 0 20 100 70 40 30
Sandpoint 30 38 34 40 31 34 / 10 20 100 90 60 40
Kellogg 31 40 34 38 30 34 / 10 10 90 100 50 50
Moses Lake 33 40 36 45 30 42 / 0 20 80 30 10 10
Wenatchee 32 38 31 40 28 37 / 20 40 100 30 20 10
Omak 30 36 32 37 26 34 / 10 50 100 40 10 20

&&

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

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