128
FXUS66 KOTX 100941
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
141 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 norths
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 precipitatable 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...
06Z TAFs: Rain is on the increase this evening east of the
Cascades as a warm front with a strong plume of moisture lifts
over the region. Rain will become widespread into the evening
bringing deteriorating conditions and lowering ceilings. The
moisture plume will also be accompanied by a strong low level
jet with low level wind shear particularly at KPUW through 16z
Wednesday morning. Expect moderate rainfall intensity at times
overnight that will lower surface visibility with IFR conditions
developing, especially between 06-13Z. Westerly winds will also
be picking up by the early morning hours on Wednesday and
increasing into the afternoon. 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.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Confidence is
high on MVFR and at least isolated/temporary IFR conditions as
rain increases tonight.

-----------------------

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 from 6 AM this morning to 7 AM PST Thursday for
     Spokane Area-Upper Columbia Basin-Washington Palouse.
     High Wind Warning from 6 AM this morning to 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 from 6 AM this morning to 7 AM PST Thursday for
     Coeur d`Alene Area-Idaho Palouse.

&&

$$