020
FXUS66 KOTX 032332
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
332 PM PST Wed Dec 3 2025

.KEY MESSAGES...

- Wintry mix Thursday into Friday may result in a slick
  commutes.

- Warming temperatures and a transition of snow to rain late
  this week with breezy winds.

- Moderate impacts from snow expected on the mountain passes
  late week into the weekend.

- Increased potential for rock slides next week with a mild and
  wet weather pattern.

&&

.SYNOPSIS...
The weather will trend much more unsettled Thursday through the
weekend. Temperatures look to be cold enough tonight into
Friday to support a lowland wintry mix. By Friday, temperatures
will modify and warm above normal with unsettled weather
continuing through the weekend and into next week.

&&

.DISCUSSION...

...MIXED VALLEY PRECIPITATION AND MOUNTAIN SNOW THROUGH THIS WEEKEND
TO BRING THE POTENTIAL FOR TRAVEL IMPACTS...

Tonight through Saturday night: An active storm track with a robust
upper level jet directed at the Northwest Region will delivery
multiple rounds of shortwave disturbances and precipitation. The
orientation of the jet will be northwest to southeast and draped
squarely over the Northwest. There will also be a nearly constant
supply of moisture into the region as well, and this will result in
a consistent period of precipitaiton over the Cascade crest and into
the Idaho Panhandle. The first shortwave comes late tonight into
Thursday night. Lift will primarily be supplied with weak isentropic
ascent at low to mid levels over easter Washington and then
favorable orographics along the Cascade crest and especially so over
the Central Panhandle Mountains. We are teetering between snow,
rain, and freezing rain across the region making for a challenging
precipitation type forecast. The stable thermal profile with an
expansive low stratus deck across much of the region into the
mountain valleys today has prevented much warming in the afternoon
with highs over much of the lowland areas running in the low 30s.
With that, dew point temperatures are generally running generally
between 29-33 degrees. There is opportunity for these
temperatures to wetbulb slightly cooler and we will see
temperatures tomorrow morning running near to or a degree or
two below freezing for the northern portions of the Columbia
Basin to the Waterville Plateau where a warm nose aloft looks to
nudge in. This will set up the potential for light freezing
rain. However, the moisture expected to fall is expected to be
very light and may not measure over much of the area that will
see the better potential for freezing rain. As such, the
freezing rain threat looks notable for Thursday morning
generally across the Highway 2 corridor of the Columbia Basin to
the Moses Lake Area, but not significant enough for a Winter
Weather Advisory.

Thermal profiles for the northern mountain valleys should
remain cold enough for precipitation to fall as snow. Moisture
will again be lacking for much in the way of significant
accumulation (1+ inches of snow) except for at the Cascade crest
and the Central Panhandle Mountains. Snow levels will be rising
through the day on Thursday over the Cascades where snow is
expected to transition to rain. This will not be the case in the
Central Panhandle Mountains however. The Silver Valley will see
a transition to rain by Thursday evening, but elevations above
3,000 feet look to remain as snow. This is expected to result in
travel impacts along I-90, especially for 4th of July Pass and
over Lookout Pass where 4 to 8 inches of snow is expected.

Precipitation will decrease late Thursday night into early Friday
morning, but additional shortwave disturbances will re-intensify
moist isentropic ascent with a warm front boundary that moves
across Friday morning. This boundary will bring light
precipitation across the Columbia Basin as well, and
temperatures will continue to be flirting right around freezing
at the surface. This warm front looks a bit wetter and could
bring a better potential for freezing rain across the Highway 2
corridor from the Waterville Plateau and the Upper Columbia
Basin, as well as into the mountain valleys of north- central
and northeast Washington, the uncertainty with freezing rain and
potential for ice accumulation will be surface temperatures.
They will be right around the freezing mark, especially along
that Highway 2 corridor and will be warming through the morning.
If temperatures start out a little colder early Friday morning,
then freezing rain may be more of an impact than what is
forecast.

The other areas of concern will be for mixed precipitation in the
valleys of the Northeast Mountains and North Idaho. There is
uncertainty here on snow levels and how quickly they will increase
as moisture increases later in the day. Total snow accumulations are
expected to be up to 2 inches for these valleys. Colder pockets,
especially closer to the Canadian border, may see higher
accumulations than this. Snow will be heavy and wet and will be
slick to drive on. Updates may be needed to adjust these
accumulations and possibly may need winter weather advisories for
this part of our forecast area if a cooler, snowier forecast
looks more likely. Where confidence is higher for significant
snowfall impacts are expected is in the Central Panhandle
Mountains for Friday with the warm front, and also continued
orographics with northwest flow into Saturday. Snow levels will
be increasing from around 3,000 feet with the warm front to
4,500 feet by Friday evening. A Winter Storm Watch is in effect
for Friday through Saturday for 5-13 inches of additional snow.
Snow may see a transition to rain in that 3,000-4,000 feet range
fast enough that 4th of July Pass may not see heavy snow, but
Lookout Pass does look to with a greater than 80% chance for at
least 8 inches of snow over this period.

EXTENDED PORTION OF THE FORECAST CALLS FOR MILDER TEMPERATURES,
MULTIPLE ROUNDS OF PRIMARILY RAIN, AND BREEZY TO WINDY AT TIMES-

Sunday through Wednesday: A pair of Atmospheric River (AR) plumes
will be directed into the Northwest for the latter half of the
weekend into early next week. The first AR will be weaker and just a
precursor to conditions to come. A shortwave disturbances on
Sunday will deliver more wet weather with higher snow levels.
This will mean rain in the valleys and snow primarily just above
3,500 feet. Additional light snow is expected at Stevens Pass
and Lookout Pass for Sunday. Impacts at these passes look to be
minor at best though. Then a solidly moderate AR (potentially
strong) is expected to move in on Monday and potentially remain
in place over the Northwest through Wednesday. Heavy rain across
the Cascade crest and over the Idaho Panhandle will increase
the potential for hydrology related impacts. Snowmelt is
expected at low to mid elevations. Rain across the Cascade crest
is expected to be soaked in, and there isn`t enough to suggest
that to combination of rain on snowmelt will result in any
flooding impacts in the Idaho Panhandle. Main concern right now
is for an increased risk of rock slides with soils thawing out
and the potential for moderate to heavy rain to saturate soils.
The extended portion of the forecast will be revised and updated
as models come to consensus on how strong the AR will be and
duration over the region. /SVH

&&

.AVIATION...
18Z TAFs: Widespread low stratus across the Inland Northwest
today with IFR to MVFR conditions and localized low IFR
conditions specifically around KGEG and KDEW and up the Methow
Valley. Light southeasterly flow may erode the stratus deck
across the Palouse. Increasing ceilings around KLWS and KPUW
is expected to result in VFR conditions in the afternoon. Not
expecting the stratus to erode as far north as KGEG/KSFF/KCOE or
west as KMWH/KEPH though. A weak mid level frontal system will
move in Thursday morning and spread light preciptiation across
the region after 10Z. A warm tongue will be present in the lee
of the Cascades into the western Columbia Basin where a mix of
rain and freezing rain is expected. This includes KEAT/KEPH/KMWH
where a chance of freezing rain (30-50% chance) is more likely
and light rain more likely for KEPH and KMWH. Warmer air will be
slower to move into KPUW/KGEG/KSFF/KCOE where light snow is
expected as the dominant precipitation type for Thursday
morning.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Moderate to high confidence that low stratus will persist over
much of the Columbia Basin today with IFR to MVFR conditions for
KEAT/KMWH/KGEG/KSFF/KCOE. Moderate confidence that ceilings
will lift at KPUW and KLWS by this afternoon with VFR conditions
prevailing. Low confidence for freezing rain to fall at or near
KEAT and KMWH for Thursday morning after 11Z. /SVH

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

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        30  35  31  38  34  44 /  10  60  50 100  50  30
Coeur d`Alene  31  35  31  39  35  42 /  20  70  60 100  80  60
Pullman        30  36  32  42  38  44 /  10  80  80 100  80  60
Lewiston       32  39  36  47  42  51 /   0  80  80 100  80  50
Colville       28  36  24  37  25  40 /  20  40  40  90  60  40
Sandpoint      30  34  28  36  32  39 /  40  70  60 100  90  80
Kellogg        31  35  33  40  37  40 /  30  90  80 100 100  90
Moses Lake     31  37  30  42  33  49 /  10  50  40  70  10  10
Wenatchee      31  39  33  46  38  49 /  20  40  50  80  50  30
Omak           30  37  29  38  31  42 /  20  30  30  80  40  10

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...None.
ID...Winter Weather Advisory from 7 AM Thursday to 4 AM PST Friday
     for Central Panhandle Mountains.
     Winter Storm Watch from late Thursday night through Saturday
     afternoon for Central Panhandle Mountains.

&&

$$