548
FXUS66 KOTX 021815
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
1015 AM PST Tue Dec 2 2025

.KEY MESSAGES...

- Light snow through this morning, especially in the Central
  Panhandle Mountains and Palouse.

- 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.

&&

.SYNOPSIS...
A weather system pass through this morning will bring light
snow, mainly to the Idaho Panhandle and extreme Eastern
Washington. Temperatures will modify and warm above normal late
this week. Unsettled late this week as well with snow
transitioning to rain in the lowlands.

&&

.DISCUSSION...

Tuesday afternoon through Wednesday: As a ridge off the PNW
coast strengthens and higher heights prevail, PWATs will drop
down to 90- 100% of normal, leading to a brief break from any
wintry precipitation. Lingering snow chances in the Cascades and
Idaho Panhandle mountains exist due to orographic lift, but
these totals will be minimal. Biggest impacts during these days
is the potential for fog formation combined with subfreezing
temperatures.

Thursday through Sunday: Now here`s where things get interesting. On
Thursday, the ridge will flatten, ushering in warm and moist
subtropical air. By Saturday, PWATs rise to 150-200% of normal, and
temperatures rise to nearly 10 degrees above average for this time
of year due to the warmer air moving in. With this active weather
pattern setting up, much of the area will see steady precipitation
through the weekend, with the highest accumulations happening Friday
night through Saturday. Due to the warmer nature of the system, snow
levels will be higher with this storm. Main impacts precipitation
wise will be seen in the mountains and northern valleys, with much
higher totals than this last system anticipated at mountain passes.
Current NBM probabilities for 6 inches of snow or more sit at
75% for Washington Pass, 40% for Stevens Pass, and 20% for
Lookout Pass through Sunday. Should these probabilities stay
consistent through the next couple days, winter weather
highlights will likely be needed for wintry conditions at
mountain passes. With higher snow levels, the lowlands will
mostly see rain, but there is the chance for some flakes in the
Spokane/CdA area. The Spokane, Pullman, and Lewiston areas have
a 20-40% chance of seeing more than 0.25 inches of rain through
Sunday. Alongside this precipitation, as a surface low drops
into Montana, it will create a tight pressure gradient across
the state with the high off the coast and lead to elevated winds
through the weekend. Through the weekend, Spokane, Wenatchee,
Ephrata, and Moses Lake have a 20-30% chance of seeing maximum
wind gusts up to 35 mph, and Lewiston and Pullman have a 34-45%
chance. There is some disagreement in the models with winds, as
probabilities have come down since yesterday, but there are
still enough signals of gusty winds that it`s worth mentioning.

Monday through Wednesday: Long-term guidance and clusters indicate a
continued pattern of active winter weather beginning next week.
Roughly half of the clusters show lower heights moving through the
area on Monday, with the other half showing continued higher
heights. All clusters, however, show a series of shortwaves moving
through the state of Washington early next week. Right now,
probabilities are showing very similar probabilities as mentioned
above for mountain passes seeing another 6 inches of snow. Of note,
the Extreme Forecast Index shows a chance of higher than normal
winds, especially on Tuesday. NBM probabilities of maximum wind
gusts agree, with nearly the entire forecast area having a 50-70%
chance of seeing maximum wind gusts of 35 mph or more. The CPC is
also messaging a moderate chance of high winds throughout our
forecast area in their 8-14 day probabilistic hazards outlook. Since
the air moving in over the weekend is warm and moist, temperatures
will be above normal for this time of year. We`ll continue to keep a
close eye on early next week, since further winter headlines may be
needed. /AS

&&

.AVIATION...
18Z TAFs: Snow showers are moving across far southeast
Washington and the southern Idaho Panhandle as of 18Z and will
clear in the next hour or two. Widespread LIFR to MVFR
conditions are being observed in the wake of this system. A
drier northwest flow as a ridge noses into the Inland Northwest
will bring a chance for low stratus and fog to clear at
KEAT/KMWH/KGEG/KSFF/KCOE between 20-23Z, but confidence is low
for KGEG/KCOE and moderate for KSFF. Models give higher
confidence for stratus/fog to persist at KPUW/KLWS through the
period. Risk of widespread IFR/LIFR conditions returns this
evening as stratus spreads to the north into KGEG/KSFF/KCOE and
then to the west into KMWH/KEAT overnight.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
Models have trended a pessimistic for this afternoon (20-23Z),
with a 30% chance for VFR conditions at KGEG/KCOE, and a 50%
chance for KSFF. However, there is a 70% chance for a return to
VFR for KEAT and KMWH. Confidence is high for conditions to
deteriorate for after 03/04Z for KGEG/KSFF/KCOE, after 06Z for
MWH, and around 10-12Z for KEAT.

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

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        34  24  36  29  34  30 /  80   0   0  10  40  40
Coeur d`Alene  35  27  38  29  35  31 /  80   0  10  40  60  50
Pullman        35  28  38  26  35  31 /  80  10  10  20  50  60
Lewiston       41  33  42  31  40  36 /  80  10   0  10  30  60
Colville       37  19  37  23  35  24 /  20   0  10  10  40  40
Sandpoint      34  25  35  28  34  29 /  50  10  20  60  70  60
Kellogg        35  29  38  31  35  34 /  90  10  30  60  80  70
Moses Lake     38  24  38  26  35  28 /  20   0   0   0  20  20
Wenatchee      39  30  41  30  39  33 /  10   0   0  10  20  30
Omak           39  27  39  27  36  29 /   0   0   0   0  20  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory until 9 AM PST this morning for
     Spokane Area.
     Winter Weather Advisory until 11 AM PST this morning for
     Washington Palouse.
ID...Winter Weather Advisory until 9 AM PST this morning for Coeur
     d`Alene Area.
     Winter Weather Advisory until 11 AM PST this morning for
     Central Panhandle Mountains-Idaho Palouse-Lewis and
     Southern Nez Perce Counties.

&&

$$