Moscow, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

901
FXUS66 KOTX 251151
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
351 AM PST Thu Dec 25 2025

.KEY MESSAGES...

- Areas of dense fog Christmas morning
- Moderate to heavy snow over mountain passes Friday into Friday
  night
- Periods of rain and snow Thursday and Friday
- Snow levels lowering Friday with potential for light snow in
  valleys of Northeastern Washington and North Idaho
-

&&

.SYNOPSIS...
The Inland Northwest continues to be under an active pattern
with several opportunities for impactful mountain snow, light
lowland rain and snow, and breezy winds. Cooler temperatures
with drier conditions Friday into the weekend with moderate
confidence for dry conditions to persist early next week.

&&

.DISCUSSION...
Christmas Day/Night: We are starting off Christmas Day with
areas of dense fog across the Western Columbia Basin and low
stratus across much of northern WA and North Idaho. We have
received reports of patchy dense fog in Northeastern WA but
coverage looks very localized. Main message to those traveling
this morning, be prepared fog and leave extra time to reach your
destination safely.

In regards to precipitation: The INW is currently on the
backside of one shortwave with showers slowly crossing into
Montana but low pressure spinning off the WA Coast will send a
few more impulses into the region today with additional rain and
or wintry mix for some. The next band of light precipitation
will lift south to north this morning 6AM-11AM. Based on the
latest observations and projected midlevel temperatures, we are
are looking similar precip types for the Cascades, Waterville
Plateau, and northern mountains (snow/wet snow) with generally
light accumulations. Will need to keep a close eye on the
Waterville Plateau and few valleys in the Okanogan Highlands,
and extreme southwestern Columbia Basin between George and
Vantage where temperature profiles are showing the potential for
a light wintry mix which could have brief freezing rain, snow,
and sleet.

In the wake of the morning band of precipitation, additional
showers will arrive Christmas evening and into Christmas night.
The offshore trough will begin to swing inland with upper-
levels cooling. This will result in steepening lapse rates and
threat for heavier, more convective showers. Models are showing
up to 100 J/kg of CAPE over the Idaho Panhandle and eastern
third of WA and would not rule out a rogue lightning strike or
two. Consequently, the storm prediction center has the area
painted in general thunder.

On Friday, two additional shortwaves swing through the region.
One comes through southeastern WA and the lower Idaho Panhandle
Friday morning followed by a second, northern branch Friday
evening and night. The air mass will continue to cool Friday
with 850mb temperatures cooling near 0C around midday then -3C
or colder overnight. While bands of preciptiation will start off
as lowland rain and mountain snow, snow levels will be lowering
with time with potential for wet snow mixing down toward valley
floors, especially going into Friday evening and night. During
this time, precipitation will end in Central WA outside snow
showers on the Cascade crest and passes. Main focus for light
snow accumulations will be over the Idaho Panhandle and just
over the border into Washington minus the L-C Valley. Hard to
get excited about accumulations in Spokane but but there is a
20-50% chance for an inch of snow for locations like Ione,
Newport, Sandpoint, Kellogg, Deary, St Maries, and even Pullman.

One area that will have snow throughout the day Friday and into
Friday night will be Lookout Pass. NBM is indicating 6-10
inches with snow starting with the first wave Friday morning.
There is some uncertainty how effective the snow will be on the
roads Friday morning and moderate chances for impacts to be
minimal around midday only to deteriorate with heavy snow
showers Friday evening. If traveling Friday, be prepared for
winter travel conditions as cooler air finally works its way
back into the area.

Saturday-Sunday: Fairly drastic shift in the weather pattern
with a drier and colder continental air mass settling into the
region. It will feel a bit more like December with overnight
lows in the teens and 20s and highs in the 30s. The incoming
flush of cooler air should bring some reprieve from the moist
boundary layer, reduced low clouds/fog and even decent odds for
afternoon sunshine. Models hint a few very weak waves slipping
through with flurries though this comes with low confidence.

Monday-Thursday: Seeing a similar signal in the medium range
guidance with strong support for a ridge of high pressure
delivering stable weather conditons and dry conditions for
Monday and Tuesday and potentially into Wednesday. Roughly 35%
of the ensembles begin to shift the ridge axis east into Western
MT Wednesday which increases to 50% by Thursday. While the
ridge is flatter early in the week, can`t rule out light snow
near the Canadian border but overall, thinking we are heading
into a period with very low weather impacts outside morning fog.
Once the ridge slides east, look for increasing chances for
precipitation and return to unsettled weather conditions...if
and when this occurs. /sb

&&

.AVIATION...
12Z TAFs: A moist boundary layer will continue to provide IFR,
local MVFR conditions at GEG/SFF/COE/MWH/EAT, along with patchy
fog. The potential for a developing easterly flow to advect fog
toward GEG will continue to warrant a tempo 1/2 mile fog this
morning. MVFR/VFR conditions at PUW/LWS. Bands of precipitation
lift in starting around 15-18Z, with others through the
afternoon. This will be as rain for most TAF sites, with some
snow or a rain-snow mix near EAT. Some patchy freezing rain may
also be embedded in that precipitation near EAT, but the risk is
low.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Confidence
levels for restrictions through the next 6-10 hours is low for
hour by hour trends given partial breaks in the high clouds and
very small temperature/dewpoint trends. Fog could be quick to
develop with any breaks. Additionally, easterly winds will begin
to increase with tendency for boundary layer moisture to slosh
into Central WA and KEAT. Easterly winds have a tendency of also
supporting IFR conditions at KGEG when low stratus present at
KSFF as this cloud deck advects to the west. There is also
marginal LLWS for KPUW, KSFF, KGEG 20-23z with a 35-40kt jet
from the southwest. This will be monitored.

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

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  33  41  25  32  19 /  60  60  90  70  10   0
Coeur d`Alene  46  35  41  24  31  16 /  60  80  90  90  20   0
Pullman        48  36  41  27  31  21 /  50  50  90  90  40   0
Lewiston       51  38  47  33  38  26 /  30  40  70  80  30   0
Colville       41  31  40  19  29  14 /  80  70  90  70  10   0
Sandpoint      43  35  39  25  30  16 /  80  90 100 100  30   0
Kellogg        47  36  39  25  29  14 /  70  80 100 100  50   0
Moses Lake     44  32  40  25  35  20 /  50  40  50  20   0   0
Wenatchee      36  30  35  25  33  21 /  70  30  50  30   0   0
Omak           36  31  36  20  30  16 /  80  40  50  30   0   0

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...Winter Weather Advisory from 4 AM Friday to 10 AM PST Saturday
     for Northeast Blue Mountains.
     Dense Fog Advisory until 7 AM PST this morning for Moses Lake
     Area-Upper Columbia Basin.
     Winter Weather Advisory from 4 AM to 10 PM PST Friday for
     Western Chelan County.
ID...None.

&&

$$