200
FXUS66 KOTX 231952
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
1152 AM PST Sun Feb 23 2020
.SYNOPSIS...
A vigorous storm system will bring a round of valley rain and
mountain snow today followed by windy conditions this afternoon.
Shower chances continue Monday, especially around the mountains.
Drier weather returns Tuesday. The next appreciable chance of
precipitation comes toward next weekend.
&&
.DISCUSSION...
Morning update: A strong cold front is rapidly advancing east
across Eastern WA late this morning with models showing the front
reaching NW Montana by late afternoon. Gusty winds, a thunderstorm
threat, rain, mountain snow, and even patchy blowing dust to talk
about.
Wind: Winds have been gusty alongand ahead of the front with
weather stations thus far showing wind gusts of 46 MPH in Othello
and 50 MPH in Hermiston, OR. As the front continues to move east
the HRRR shows a burst of wind pushing east with gusts ranging
from 35-50 MPH across the Spokane area south through the palouse,
Lewiston area and Camas Prairie. The wind advisory has been
expanded to include the Lewiston area and Camas Prairie. Meanwhile
behind the front winds will be increasing due to cold advection,
a tight pressure gradient, and momentum mixing as a surface low
tracks across southern BC. Remainder of wind advisories look on
track. Across SE Washington into the Lewiston area radar shows a
convective component to the front which may allow locally stronger
gusts to mix down.
Thunderstorms: There remains a slight chance of thunderstorms this
afternoon across SE WA up into the Spokane area with models
showing a few hundred joules of SB CAPE. If storms develop locally
stronger wind gusts in excess of 50 MPH are possible.
Blowing dust: It is early in the season for blowing dust. However
the strong winds have picked up some blowing dust as seen on area
web cams south of our area across Tri Cities, Walla Walla, and
Hermiston. Some of this dust may reach the palouse early this
afternoon but rain with the front should quickly limit this
threat.
Mountain snow: As the front continues to move east a burst of
mountain snow is expected for N Idaho early this afternooon
followed by bands of snow for the Central Panhandle Mountains
tonight with snow levels lowering to the valley floors. For the
Cascades bands of snow showers will continue to impact travel over
the passes near the Cascade crest. JW
&&
.AVIATION...
18Z TAFS: A quick hitting cold front will produce a brief period
of precipitation to our TAF sites today followed by several hours
of gusty winds. Look for the main frontal band to push through
central Washington and across the Idaho Panhandle between 18z and
22z with an hour or two of rain or rain/snow mix. There may be
some post frontal showers into the evening, but the main impact
behind the front will be the gusty west wind. Peak gusts as high
as 30 to 40kts will be possible through 03z. Look for winds to
gradually subside through the night with most TAF sites in the 10
to 15 mph range by sunrise Monday. /GKoch
&&
.PRELIMINARY POINT TEMPS/POPS...
Spokane 46 30 43 24 43 29 / 90 20 0 0 0 10
Coeur d'Alene 44 30 40 23 41 28 / 90 30 10 0 0 0
Pullman 44 30 39 25 41 31 / 90 30 10 0 0 10
Lewiston 54 35 46 30 47 35 / 70 20 10 0 0 0
Colville 46 26 45 21 43 25 / 90 10 0 0 0 10
Sandpoint 40 30 40 21 38 26 / 90 60 30 0 0 20
Kellogg 39 29 35 21 37 28 / 100 80 50 0 0 10
Moses Lake 51 31 49 26 47 28 / 60 10 0 0 0 0
Wenatchee 49 31 44 26 43 30 / 20 30 0 0 0 10
Omak 46 28 43 25 41 28 / 20 20 0 0 0 10
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
ID...Winter Weather Advisory until 10 AM PST Monday for Central
Panhandle Mountains.
Wind Advisory until 6 PM PST this evening for Coeur d'Alene Area-
Idaho Palouse-Lewis and Southern Nez Perce Counties-
Lewiston Area.
WA...Winter Weather Advisory until 4 AM PST Monday for the cascade
crest including highway 2 between coles corner and stevens
pass for East Slopes Northern Cascades.
Wind Advisory until 6 PM PST this evening for Lower Garfield and
Asotin Counties-Moses Lake Area-Spokane Area-Upper Columbia
Basin-Washington Palouse-Waterville Plateau-Wenatchee Area.
&&
$$
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