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fxus66 kotx 200404 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
804 PM PST sun Nov 19 2017

Synopsis...
rain and mountain snow will spread into the inland northwest this
evening and persist through the night. A series of storm systems
will produce several rounds of rain this week. Snow levels will be
quite high Tuesday, Wednesday, and Thursday allowing motorists to
travel over mountain passes on wet pavement. Snow levels will
begin to lower just as travelers are heading home late Saturday
and Sunday.

&&

Discussion...
update: rain and snow has developed along the east slopes of the
Cascades this evening as a wet frontal boundary sags over the
area. Web cams show snow for the Methow Valley, Stevens Pass, Loup
Loup ski area, and rain in Leavenworth. Of concern this evening
is the precipitation intensity which will likely help lower the
snow level a bit with some evidence of this already at Coles
Corner where rain is now mixing with snow and may change to all
snow this evening with light accumulations. Overnight milder air
aloft flood into Chelan County which should change snow to rain
for most areas while a deep isothermal layer near 32f in the
Methow Valley may keep precipitation as snow. All in all...not
much change to expected accumulations with the highest amounts
near the crest above 3000 feet with as much as 6 to 10 inches.
Snow accumulations for Mazama were increased to around 5 inches as
well. Localized warning amounts are expected in the mountains but
with this being near the crest and with much less snow east of
the crest including Loup Loup and Blewett Pass will not issue any
highlights at this time but maintain hazardous weather outlook.
Although will be monitoring web cams closely through the remainder
of the evening.

Elsewhere as the frontal bands sags south and east tonight rain
and mountain snow will develop. Pockets of wet snow are also
possible in the northern valleys with wet bulb temperatures this
evening in the mid 30s. Jw

&&

Aviation...
00z tafs: precipitation will spread into the inland northwest this
evening, continuing as showers on Monday. Keat and kmwh should
remain VFR with very little rain tonight. They may see some
showers during Monday but conditions should remain VFR. To the
east, the airports should stay MVFR tonight with the rain, but
then approach IFR cigs in the morning. Conditions should improve
in the afternoon. Rj

&&

Preliminary point temps/pops...
Spokane 39 45 37 48 45 55 / 100 70 20 100 100 60
Coeur D'Alene 38 44 36 46 43 54 / 90 90 20 100 100 60
Pullman 40 46 40 50 47 58 / 100 100 20 90 90 50
Lewiston 45 52 43 54 48 61 / 90 90 20 80 90 40
Colville 35 45 33 42 38 50 / 80 10 10 100 90 60
Sandpoint 35 41 33 42 40 49 / 90 90 10 90 100 80
Kellogg 33 41 35 44 41 50 / 100 100 30 90 100 70
Moses Lake 41 50 36 47 41 56 / 80 10 10 90 80 50
Wenatchee 33 48 35 44 38 52 / 60 10 10 90 60 50
Omak 36 44 34 43 39 50 / 70 10 10 90 80 40

&&

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

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