Area Forecast Discussion
Issued by NWS Spokane, WA
Issued by NWS Spokane, WA
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FXUS66 KOTX 101216
AFDOTX
Area Forecast Discussion
National Weather Service Spokane WA
416 AM PST Wed Dec 10 2025
.KEY MESSAGES...
- Heavy mountain rain will bring a risk for flooding in the
Cascades and the Idaho Panhandle. Potential for moderate to
major flooding along the Entiat River and Wenatchee River in
the Cascades.
- Strong winds across southeast Washington for Wednesday and
Wednesday night.
&&
.SYNOPSIS...
An active weather pattern will impact the area through the week.
A series of warm and wet weather systems will result in periods
of heavy mountain rain, lowland rain, high mountain snow, and
gusty winds. Strong winds will occur on Wednesday into Wednesday
night. Drier conditions arrive Thursday night into weekend, but
showers at times will be possible with weaker weather systems
possible and quicker shots at additional precipitation.
&&
.DISCUSSION...
STRONG LONG DURATION ATMOSPHERIC RIVER EVENT TO BRING
FLOODING, ROCK/MUD SLIDES, AS WELL AS STRONG WINDS THROUGH
THURSDAY MORNING...
The next atmospheric river has arrived and will remain nearly
stationary into tonight with precipitable water values of
250-325% of normal. A warm front has helped in developing
widespread precipitation early this morning but this will be
changing. After the the front passes, rain is expected to become
mainly focused again over the Cascades and ID Panhandle through
Thursday as strong downslope for off the Cascades dominates across
most of Central and Eastern Washington. Snow levels will be very
high today, rising to 7500-9000 feet this morning, before falling
over northern Washington and the North ID Panhandle to 4000-5000
feet on Thursday as precipitation intensity begins to decrease. In
addition to the heavy rain, the high snow levels and windy
conditions will accelerate snow melt, adding additional runoff
into rivers and streams in the Cascades and ID Panhandle. A Flood
Watch remains in effect through Friday morning for Chelan county,
and into Friday afternoon for Shoshone, Kootenai, and Benewah
counties. The ECMWF, GFS, and Canadian Ensembles are still
producing another 3-6 inches of rain in Western Chelan county,
with up to 6-10 inches along the Cascade crest. For the ID
Panhandle 1-4 inches is forecast. In the Cascades river rises will
be monitored closely for the Stehekin, Wenatchee, and Entiat
Rivers which are under Flood Watches. For the ID Panhandle the St
Joe and Coeur d`Alene Rivers are the main concern and are also
under a Flood Watch. Another concern for the Cascades will be
rock/mud slides, especially so in steep terrain and near newer
burn scars including the Pioneer above Stehekin, Sugarloaf, and
Labor Mountain burn scars.
Another story will be the abnormally warm temperatures and strong
winds. The atmospheric river brings an increase in southwest
winds as 850mb winds increase again to 50-60 kts across Southeast
Washington and up into the Spokane area. Currently the models are
showing limiting mixing today and it`s unlikely for these stronger
gusts to mix down. Yet, winds will still be very gusty with
sustained winds 25-35 MPH with gusts up to 55 MPH for the
Spokane/Coeur d`Alene area, Palouse, and Upper Columbia Basin. A
High Wind Warning is in effect for the Alpowa Summit and Pomeroy
areas with gusts up to 60 MPH today. The gusty winds combined with
very mild 850mb temperatures of 5-9C will yield very mild
temperatures. High temperatures today will reach the mid 50s to
mid 60s over of the Columbia Basin, and down into the LC Valley,
which would be near records. And Wednesday Night lows will only
drop into the upper 30s and 40s, except mid 50s for the LC Valley.
These temperatures are as much as 20 to 25 degrees above normal.
Thursday Night through Monday: The atmospheric river lifts north
and weakens heading into Friday but enough moisture and upslope
flow lingers in the Cascades and ID Panhandle for more
precipitation but with decreasing intensity. On Sunday into
Monday ensembles show another round of precipitation moving in
as moist precipitable water plume around 175-200% of normal
takes aim at the area from southwest to northeast. Some of the
deterministic solutions even briefly increase these values to
250% of normal. This is likely to be another mild system with
rain and high mountain snow, but amounts looks much less
compared to those this week. JW
&&
.AVIATION...
12Z TAFs: Overnight rain has brought a cool, moist boundary. It
is causing widespread IFR/MVFR CIGS/VIS across the region. A
strong low level jet is also pushing across the region with low
level wind shear particularly at KPUW through 16z Wednesday
morning. Gusty southwest winds expected for into the 30-45 kts
across the Basin. Downslope winds off the Cascades will help dry
out the boundary layer as well allowing CIGS to rise into the
afternoon to mainly VFR for the TAF sites. VFR conditions are
forecast to continue for KEAT-KMWH-KLWS-PUW. MVFR CIGS will
return to KGEG-KSFF-KCOE. HREF is showing high probability 70+%
of MVFR ceilings and 40% of IFR.
.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Confidence is
high for improving conditions through the day. Ceilings could
hover around the MVFR/VFR line. Moderate to High confidence for
MVFR ceilings to return to the KGEG-KSFF-KCOE overnight. /JDC
-----------------------
Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance
For additional probabilistic information for NWS Spokane
airports,please refer to the Aviation Dashboard on our
webpage: https:/www.weather.gov/otx/avndashboard
&&
.Preliminary Point Temps/PoPs...
Spokane 54 48 53 40 50 40 / 50 20 20 30 30 20
Coeur d`Alene 53 47 52 40 50 41 / 80 70 60 50 50 30
Pullman 55 48 52 45 52 41 / 80 10 60 60 30 20
Lewiston 63 54 60 49 60 44 / 40 10 20 50 20 10
Colville 50 39 48 31 44 33 / 40 30 10 20 40 30
Sandpoint 49 44 50 36 45 39 / 90 90 80 50 70 60
Kellogg 50 46 49 43 48 41 / 100 90 90 70 80 50
Moses Lake 60 47 56 40 55 38 / 20 10 10 10 0 10
Wenatchee 58 46 52 43 55 40 / 70 30 10 20 10 10
Omak 49 39 49 34 45 36 / 60 10 10 10 20 20
&&
.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Wind Advisory until 7 AM PST Thursday for Spokane Area-Upper
Columbia Basin-Washington Palouse.
High Wind Warning until 7 AM PST Thursday for Lower Garfield
and Asotin Counties.
Flood Watch through Friday morning for Central Chelan County-
Wenatchee Area-Western Chelan County.
ID...Flood Watch through Friday afternoon for Central Panhandle
Mountains-Coeur d`Alene Area-Idaho Palouse-Northern
Panhandle.
Wind Advisory until 7 AM PST Thursday for Coeur d`Alene Area-
Idaho Palouse.
&&
$$