Area Forecast Discussion
Issued by NWS Spokane, WA

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828
FXUS66 KOTX 231158
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
358 AM PST Sun Nov 23 2025

.KEY MESSAGES...

- Light snow returns to the mountain passes Sunday evening and
  night.

- Gusty winds with a cold front passage Sunday night through
  Monday.

- Valley snow potential Tuesday night into Wednesday. Moderate
  snow on the mountain passes.

&&

.SYNOPSIS...
A low pressure system will move today and in tonight, with some
mountain snow and rain chances. Gusty winds also develop tonight
into Monday. Snow will impact the mountain passes beginning this
evening and again Tuesday night into Wednesday. This midweek
system will bring the potential for light snow in the lowlands
and moderate to heavy snow over the mountains. Lighter
precipitation possible Thursday, as mostly mountain snow and
lowland rain.

&&

.DISCUSSION...
Today through Monday night: A system will gradually shift into
the area today, with the main cold front dropping in tonight
into Monday morning, while the supporting and colder upper
trough shifts across the area during the day Monday, before
shifting east Monday night. Precipitation chances will increase
be likely this morning at the Cascades and will be increasing
over the res of the area this morning. The chances in the lee of
the Cascades and central WA will be more transient and mostly a
risk in the morning, but the potential will persistent over the
east third of WA and ID. Heading into tonight when the main
cold front drops toward the southeastern CWA the overall threat
of precipitation picks up to the most likely chances with this
system over the south-central and the east third of WA and ID
this evening and overnight. Then the best chances retreat to the
mountain zones Monday morning afternoon and wind down Monday
night into Tuesday morning.

Snow levels will average around 5-6kft today, except locally
near 4-4.5kft over Okanogan County, WA through Boundary County,
ID this morning. Snow levels drop to 3-4kft over the Cascades
and central WA and linger near 5-6kft east this evening, then by
Monday morning drop to around 1.5 to 2.5kft. For today and much
of this evening largely lowland rain and mountain snow are in
the forecast. Light accumulations are possible near Washington
Pass, with maybe 2 to 3 inches. Accumulating snow will be more
likely around Stevens and Snoqualmie Pass this evening through
Monday, with around 2-3 inches or so at Stevens and maybe 1-2 at
Snoqualmie. Toward Sherman some light accumulation is possible
this, then again later this evening into Monday there and also
Lookout Pass with 1-2 inches.

The potential for snow drops to the lowlands overnight into
Monday morning. For most of the lowland, the colder air will
coincide with decreasing precipitation, but toward the WA/ID
border, including the Idaho Palouse, some light accumulations
are possible at around 0.1 to 0.3 inches. Some the northern
mountain valleys could also see some light accumulation heading
into Monday morning, as well as the Camas Prairie.

However the thing that favors a more limited snow threat in the
lowland will be the winds that come up with the cold front,
most notable tonight into Monday. Gusts of 15-30 mph will be
possible from the Cascades out across the Columbia Basin into
the Spokane area and Palouse into the central Panhandle. Locally
stronger winds are forecast on the from the Blues to the
Palouse, with gusts near 25-40 mph possible. These then start to
abate later Monday afternoon into Monday night. Highs today
will be in the mid-40s and low 50s and the 40s to low 50s
Monday. Lows tonight will be in the 20s to mid-30s and upper
teens and 20s Monday night (into Tuesday AM).

Tuesday to Thursday will be another active period, with more
impactful weather, with mountain snow and the potential for
lowland snow. Tuesday starts off quiet, but a warm front starts
to nose in from the west Tuesday afternoon and gradually lifts
into the area Tuesday night into Wednesday. It taps into an AR,
with PWATs peaking around 175-200% of normal. That starts to
increase from Tuesday night into Wednesday morning, with the
core of it staying near the WA/OR border and lower PWATs heading
north toward the Canadian border. Some northward surge is
possible Wednesday night into Thursday morning as the primary
cold front/upper wave makes it way inland. Models are not in the
best agreement with this latter feature.

What this boils down to is precipitation chances starting to
increase from the west Tuesday night and increasing to likely
over a good portion of the area Wednesday into Wednesday night.
Modest precipitation chances continue on Thursday, but by then
some model disagreement emerges over who has the best chances.
Most chances continue around the mountains, but are the higher
focus outside of them is harder to pin down. The lee of the
Cascades and Central WA will tend to have the lower risk base on
the pattern and climatology.

 * Snow and snow levels: The biggest question is how will snow
   levels evolve. Moderate snow accumulations are forecast
   around the mountain passes, starting in the Cascades Tuesday
   evening and expanding east through the night and continuing
   through Wednesday, with least a risk for light snow Wednesday
   night and Thursday in the mountain passes too. Lowlands are
   trickier. As it stands now, snow levels start around 1-3kft
   Tuesday evening, highest around southeast WA and lower ID.
   They start to rise Wednesday morning, but not fast enough to
   eliminate the potential for accumulation around the northern
   counties, northern Basin and Spokane and CdA area, especially
   away from the downtown and lowest elevations. Then toward
   midday and continuing into Wednesday night they rise to
   3-5kft and by Thursday to 4-5.5kft. The more likely scenario
   is snow changing to rain in the lowlands as described above.
   Highs will be in the 30s to low 40s Wednesday and mostly
   lower to mid-40s Thursday, except for some upper 40s to near
   50 in the deeper Basin, Palouse and L-C Valley.

As for accumulations probabilities in the mountain passes.

For 4 inches for Wednesday

- Washington Pass 70% chance
- Stevens Pass 75% chance
- Blewett Pass 60% chance
- Snoqualmie Pass 40% chance
- Lookout Pass 25% chance

Similar chances continue for Washington Pass on Thursday, but
start to decline elsewhere.

In the lowlands, there is some potential for 1 inch of snow but
this peaks around Wednesday morning to early afternoon and is
highest around the valleys in the mountains zones, around the
Waterville Plateau and some Cascade valleys, as well as around
the WA/ID border into the higher Palouse. Those probabilities
are around 15-30%, locally near 50% or so around the Waterville
Plateau and higher Palouse. We will have to keep an eye on the
upper Columbia Basin into the West Plains too.

Friday to Saturday the area transitions to more of a
northwesterly flow, with embedded shortwave troughs dropping
through. Models are in decent agreement in the large scale
pattern, but in poor agreement on the details of those embedded
shortwaves. This degrades confidence in the evolution of any
precipitation, but there is enough potential to keep
precipitation chances alive over the region with the higher risk
in the mountains. Snow levels linger near 3-5kft Friday and
lower to between 1.2 to 2.5kft for Saturday, meaning additional
rain/snow or all snow will be possible outside the mountains.
This means cooler air returns toward Saturday.

Beyond Saturday and heading into the start of December, models
show cooling but diverge significantly on precise numbers, with
as much as a 15 degree difference in high temperature, with
some showing highs in the teens to low 20s by then an others
keeping highs in the low to mid-30s. Either way, we will be
moving away from the those opportunities for 40 degree days.
/Solveig


&&

.AVIATION...
12Z TAFs: Light rain will continue through Sunday as a front
passes through the area. Low level moisture is forecast to bring
EAT/MWH IFR/LIFR ceilings much of the period. Limited rain
chances will be found there. VFR conditions are currently in
place at GEG/SFF/COE/PUW/LWS, but conditions are forecast to
deteriorate toward MVFR Sunday afternoon with lowering ceilings
and potential for rain to drop visibilities to 4-6SM. Wind will
pick up behind the front Sunday night, particularly for PUW with
gusts 25-30 kts.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Moderate
confidence in timing of VFR conditions transitioning to MVFR
conditions. Moderate to high confidence in increasing winds for
PUW Sunday night.

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

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        48  32  43  25  40  30 /  50  60  30   0   0  50
Coeur d`Alene  46  34  42  26  40  31 /  70  80  50  10   0  50
Pullman        47  32  40  24  40  30 /  30  90  50  10   0  60
Lewiston       51  38  48  29  43  35 /  20  90  40  10   0  50
Colville       45  29  45  20  39  24 /  80  60  40   0   0  60
Sandpoint      43  33  41  25  38  28 /  90  80  70  20  10  60
Kellogg        46  34  40  27  39  32 /  70 100  80  30  20  60
Moses Lake     50  30  47  24  40  30 /  30  20   0   0  10  50
Wenatchee      50  34  46  29  40  33 /  40  20   0   0  10  60
Omak           46  32  45  26  39  30 /  30  20  10   0   0  50

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...None.
ID...None.

&&

$$