239
FXUS66 KOTX 222240
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
240 PM PST Sat Nov 22 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...
The weather will remain quiet through Sunday with near to warmer
than normal temperatures. A low pressure system will move in at
the end of the weekend. Snow will impact the mountain passes
beginning Sunday 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.
Mainly light mountain showers on Thursday.

&&

.DISCUSSION...
Saturday and Sunday: A weak ridge of high pressure is bringing
fairly mild and mostly dry conditions to the INW today ahead of an
incoming cold front. Temperatures will peak in the 40s to low 50s
today with the coolest temperatures in central WA. A stubborn low
stratus deck has led to slower than anticipated warming in central
Washington. Not often is Spokane 10 degrees warmer than Moses Lake.
A weak atmospheric river currently impacting Vancouver Island is
starting to sag south this afternoon bringing increased cloud cover
and chances for snow showers in the Cascades/northern mountains
above 6000`. Rain chances increase in the lowlands late tonight and
into Sunday morning as synoptic forcing improves thanks to an
approaching cold front. With snow levels around 4500-5500 feet, snow
impacts will be minimal. Models have slowed the progression of the
the mid-level shortwave trough, which would hamper the potential of
a convergence zone establishing in western WA. Low level flow is
favorable but lapse rates do not steepen until the shortwave passes
through Sunday night. Snow amounts look fairly light for Stevens
Pass (2-4") and Washington Pass (3-5"). Rain amounts in the lowlands
through Sunday night will be very light (0.01-0.05") in central WA
but a bit higher in eastern WA and north ID (0.10-0.25"). Southwest
winds will increase in the lowlands of eastern WA and north Idaho as
the front passes and cold advection through Monday morning with
sustained speeds around 10-20 mph gusting up to 35 mph on the
Palouse.

Monday and Tuesday: Southwest winds will continue through the early
afternoon but slowly subside in the evening hours as the shortwave
trough departs. Light precipitation will continue in the Cascades
and Idaho Panhandle mountains with strong west/northwest flow aloft.
The lowlands will be dry with highs in the 40s. Monday will be a
good travel day. Monday night will be cold with lows in the low 20s
to low 30s as drier air and fairly minimal cloud cover initially
will allow for strong radiational cooling. It would be even cooler
if a cirrus deck was not moving into the region early Tuesday
morning. Much of Tuesday will be a good day for travel ahead of
incoming weather system under the influence of a weak ridge of high
pressure.

Tuesday night into Wednesday: The upper air pattern still indicates
a mid-level ridge but changes will rapidly occur thanks to a
deepening low pressure system off the coast. What we know: A warm
front will surge through the region some time between Tuesday night
and Wednesday morning which will bring a round of moderate
precipitation to the region. What is more uncertain are the snow
levels with this system and the timing of the precipitation. Details
will be ironed out as the event comes closer. There is moderate
confidence for the antecedent air mass to be cold enough to support
lowland snow at the onset on the event. There is also moderate
confidence for the colder air to remain more stubborn in the E
Slopes of the Cascades and near the immediate Canadian border. The
details are muddy still but with Wednesday being a very busy travel
day, this forecast should be watched closely, especially since the
lowlands have not experienced a snow event in a while. Outside of
the lower Columbia Basin there is a 15-30% chance of at least an
inch of snow during this period.

Mountain pass chances of 6+" 4 PM TUE - 4 PM WED:
Stevens: 45%
Washington: 40%
Snoqualmie: 25%

6+" chance 4 PM WED - 4 PM THU further east:
Lookout: 20%

Thursday onward: By Thursday, snow levels will raise to above 5000`,
minimizing impacts to the mountain passes. Ensemble clusters are
indicating the potential for another wave which would bring
additional precip to the region late next week but confidence is
very low. /DB


&&

.AVIATION...
18Z TAFs: IFR-MVFR cloud deck will slowly start to lift and
erode early this afternoon in central Washington. Otherwise VFR
conditions will prevail with passing mid and high clouds through
this evening. An incoming weather system will bring precip
chances to portions of eastern WA and north Idaho (KEAT-KGEG-
KSFF-KCOE) starting around 12z Sunday. Models indicate low
chances (10-30%) for MVFR cigs for KGEG-KSFF-KCOE between 12-18z
Sunday with the rain incoming.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence
in timing of improvement to VFR. High confidence for continuing
VFR conditions through 12-18z Sunday.

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

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        37  46  32  43  25  39 /  20  60  70  10   0  10
Coeur d`Alene  38  46  34  42  27  39 /  20  70  90  30  10  10
Pullman        36  48  32  41  25  39 /  10  40  90  30  10  10
Lewiston       39  51  38  47  30  43 /   0  20  80  10  10  10
Colville       32  44  28  44  21  39 /  40  80  70  10   0  20
Sandpoint      36  43  33  41  25  37 /  50  90 100  50  20  20
Kellogg        39  47  34  40  28  39 /  10  70 100  60  30  30
Moses Lake     34  47  29  48  23  40 /  10  30  20   0   0  20
Wenatchee      39  48  33  46  30  40 /  20  50  20   0   0  30
Omak           37  45  31  45  27  39 /  20  40  20   0   0  10

&&

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

&&

$$