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fxus66 kotx 150558 
afdotx

Area forecast discussion
National Weather Service Spokane Washington
958 PM PST Thu Nov 14 2019

Synopsis...
a frontal system will bring rain and high elevation snow to the
Pacific northwest on Friday. The chance for light rain will
persist through the weekend and into early next week. Snow levels
are expected to remain above the majority of our mountain passes
through early next week. Cooler temperatures and drier weather
will likely return by the middle of next week.




&&

Discussion...
tonight through Friday night: ridging weakens overnight in
advance of friday's cold front which will bring rain to most lowland
locations. The ridge aloft has enough strength to allow for low
clouds and fog in lowlands and the basin to reform and/or remain
persistent in places where it has yet to dissipate. Friday night
ridging builds in the area with the jet stream showing a northwest
to southeast orientation and pointed into northeast Washington and
north Idaho Friday night which may cause higher elevations to hold
onto a bit more breezy/gusty northwest wind Friday night. Forecast
temperatures remain on the warm side of normal for this time of year
given the ridging. Snow levels will remain high enough to limit any
snow accumulations to above pass level at about 4800 feet mean sea level and
above over extreme north tapering up to around 5500 feet mean sea level for
locations roughly south of a Stevens Pass to Spokane line.
/Pelatti

Saturday through sunday: the upper level ridge returns to the inland
northwest with moisture streaming over top. This will bring plenty of
mid to high level cloudiness and a chance of light precipitation
as a warm front brushes across southern b.C. Isentropic lift
increases with low level southerly flow as snow levels rise above
6k ft with mainly rain with a small amount of high elevation snow.
Will see this feature slide east of the region Sunday night with
drier air and clearing skies. Although boundary layer moisture may
lead to patchy fog and low clouds in the valleys. Overnight lows
will remain mild in the mid to upper 30s, while daytime highs rise
from the 40s to lower to middle 50s on Sunday.

Monday through thursday: the upper ridge continues with mild
temperatures into Monday, although the next Pacific system will be
approaching with an increase of cloud cover. Interesting note, the
deterministic models indicate a dry day on Monday although over
half of the ensemble members in both the European model (ecmwf) and GFS lean toward
a small chance of precipitation. So would not rule out some light
precipitation or sprinkles during the day on Monday. The main
brunt of the shortwave pushes inland Monday night into Tuesday
with the models shows varying degrees of strength, timing and
track with a chance of rain and mountain snow. Cooling will be
expected Tuesday night into Wednesday on the back side of the
shortwave with falling temperatures and snow levels as drier and
breezy northerly flow moves into the region. Dry and cool weather
will be found by midweek with daytime highs in the 40s and lows in
the mid 20s to lower 30s, which will be closer to seasonal normals
for mid November. /Rfox.

&&

Aviation...
06z tafs: at this hour, MVFR to IFR conditions are prevalent
across klws-kmwh-keat, with LIFR conditions at kpuw. These low
clouds and fog are expected to move toward kgeg-ksff-kcoe
overnight tonight. A quick moving weather system will bring rain
across the terminals starting between 15-21z Friday, and
continuing MVFR/IFR conditions. Forecast confidence is low in the
precise timing and conditions the next 24 hours.
Dang



&&

Preliminary point temps/pops...
Spokane 33 44 33 46 37 51 / 0 90 10 10 20 30
Coeur D'Alene 34 46 34 46 39 50 / 0 90 10 20 30 50
Pullman 37 49 35 49 40 54 / 10 80 10 10 10 30
Lewiston 39 53 39 54 43 57 / 10 50 20 10 10 20
Colville 31 48 28 47 33 51 / 0 70 0 30 40 30
Sandpoint 34 46 35 44 38 47 / 0 100 20 30 50 60
Kellogg 36 48 38 44 39 47 / 10 90 70 10 30 60
Moses Lake 34 50 29 50 35 56 / 0 50 0 10 10 10
Wenatchee 35 50 35 48 37 55 / 0 70 0 20 20 40
Omak 33 46 31 46 35 51 / 0 50 0 20 30 30

&&

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

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