556
FXUS66 KOTX 152337
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
337 PM PST Mon Dec 15 2025

.KEY MESSAGES...

- Rain and high mountain snow Monday into Tuesday to bring additional
  river rises and mud and rock slide concerns to Cascades and
  Idaho Panhandle.

- High confidence for strong winds Tuesday night into Wednesday.
  Chances for wind gusts greater than 50 mph range from 60% to
  90% and 30% to 70% for greater than 60 mph winds across much
  of the region.

- High confidence for heavy mountain snow impacting the Cascades
  starting overnight Tuesday. There is a 90% chance of 2 feet
  or more of snow at Stevens Pass through Friday afternoon.

&&

.SYNOPSIS...
An extremely active pattern begins today. Rain and high
mountain snow Monday into Tuesday night will bring additional
river rises with mud and rock slide concerns in steep terrain of
the Cascades and Idaho Panhandle. Strong, potentially damaging
winds, will then develop Tuesday night into Wednesday, along
with a transition from rain to heavy snow at pass levels.
Temperatures remain above normal at the end of the week but
cooler with additional weather systems to bring mountain snow
and rain or snow in the valleys.

&&

.DISCUSSION...

...VERY ACTIVE WEATHER PATTERN THIS WEEK WITH RENEWED FLOODING
CONCERNS FOR CASCADES AND NORTH ID PANHANDLE INTO TUESDAY,
POSSIBLE HIGH WINDS TUESDAY NIGHT INTO WEDNESDAY, AND HEAVY
MOUNTAIN SNOW FOR THE CASCADES WEDNESDAY THROUGH THE END OF THE
WEEK...

Tonight through Wednesday: Through Tuesday breezy to locally
windy conditions will impact the area, with precipitation more
heavily focused around the Cascades and Idaho Panhandle
mountains. Then Tuesday night into Wednesday the precipitation
expands across the region along with much stronger winds with
the potential for widespread damage and/or impacts. The westerly
flow will carry an impulse across the region this evening into
the overnight, then a warm front lift in through Wednesday with
atmospheric river enveloping starting to impact the region,
while a cold front rapidly pushes across the area late Tuesday
night into Wednesday morning. Precipitable water values rise to
around 0.50 to 0.80 inches (180-250% of normal), peaking with
the cold front and Tuesday overnight into early Wednesday
morning will have the highest precipitation potential outside
the mountains. The mountains will see a more prolonged high
precipitation potential, relative to the lowlands. This moisture
tap is not at deep or at prolonged as recent ones. The front
will lower snow levels Tuesday night into Wednesday, bringing
rain changing to snow in the mountains. So the higher impacts
from snow will be developing Tuesday night into Wednesday,
especially near the Cascades. The Idaho Panhandle and northern
mountain passes could also see some light snow accumulation
impacts Tuesday overnight into Wednesday.

 * Precipitation amounts: the Cascades with see 4 to 5 inches of
   rain along the crest, 1.5 to 2 inches in the mid slopes, and
   0.25 to 0.5 of an inch for the valley floors. The rest of
   Washington ranges from a quarter to three quarters of inch.
   The western Basin will be lightest with near a tenth. Idaho
   Panhandle will generally range from 0.4 to 1 inch.

 * Snow: snow levels drop to around 3000 feet in the Cascades
   tonight into early Tuesday, then start to rise to around
   5-6kft during the day, before starting to drop to around
   2-3kft heading into Wednesday. Tonight into Tuesday AM the
   Cascades could see 3-6 inches of snow and 1-2 near Sherman
   Pass. Then more moderate snow is forecast for Tuesday night
   into Wednesday, with 8-16 possible near the Cascade crest and
   3-8 around the mid-slopes. Winter storm warnings are being
   issues for the Cascade crest, around places like Stevens
   Pass, for Tuesday night through Wednesday. Wind will also be
   breezy/gusty here and blowing snow may reduce visibility.
   This will be monitored should the highlight need to be
   upgraded to a blizzard warning. The other mountain passes
   could see 1-3 inches.

*  Winds:this afternoon into tonight breezy/gusty winds are in
   the forecast. This will be weaker wind impact period. Gusts
   25-50 mph will be possible. Wind advisories are in place
   through the night, but we will watch the timing. Then the
   more impactful winds are expected heading into Tuesday night
   into Wednesday. Winds speeds increase through later Tuesday
   into Tuesday night and are expected to peak with the cold
   front passage later overnight into early Wednesday. The
   stronger wind gust potential of 40-60 mph are in the forecast
   or even up to 70 mph. This has the potential to be a
   significant event, with damaging winds, significant power
   outages and difficulties for high profile vehicles. High wind
   watches remain in place.

Thursday to Monday: Another system will spread across the area
Thursday, with another around of significant precipitation
amounts. This go around snow levels will be lower, starting near
2-3kft rising to around 3-6kft in the afternoon. This will
likely bring some moderate to heavy snow in the mountains again,
with the Cascades potentially seeing feet of snow and the other
passes mountain seeing moderate snow. So stay tuned because
impacts are possible if heading into the mountain passes.
Lowlands may see a rain/snow mix to start then rain. From
Saturday to Monday a zonal flow pattern will start to set up
over the region. Precipitation potential will continue, with the
higher potential around the mountains but still moderate
outside. The Inland Northwest will have seasonal temperatures
with highs in the 30s and low 40s. Overnight lows will be in the
20s and low 30s /Solveig.

&&

.AVIATION...
00Z TAFs: A moist frontal system will impact the Inland
Northwest through tonight. Rain or rain showers will continue
to lower ceilings. Areas across NE Washington and the ID
Panhandle could see areas of VFR under moderate intensity
rainfall. Wind gusts have picked up across all TAF sites and
look to be elevated through at least 15Z for KLWS/KEAT, but will
last through the rest of the TAF period for
KGEG/KSFF/KCOE/KPUW/KMWH. Around 21Z, another wave of
precipitation moves in, leading to many PROB30 groups as PoPs
stay near 30%. Winds will steadily increase throughout tomorrow
afternoon, and especially into Wednesday morning with 45-50kts
expected at KGEG/KSFF/KCOE/KPUW/KLWS. Ceilings are projected to
drop to MVFR around 20-21Z.

.FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: Low to moderate
confidence in rain timing as precipitation moves through for
KGEG/KSFF/KCOE. Moderate to high confidence in wind gusts near
20-25kts. Moderate confidence in MVFR conditions near the end of
the TAF period due to steadier rainfall rates. /AS

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

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        55  37  50  37  45  32 / 100  30  50 100  60  10
Coeur d`Alene  52  37  48  38  45  32 / 100  60  80 100  80  20
Pullman        51  39  51  36  45  32 /  90  50  50 100  80  20
Lewiston       56  43  58  44  52  37 /  80  40  20  90  70  10
Colville       50  30  45  34  45  27 / 100  30  60 100  60  20
Sandpoint      49  37  44  37  43  31 / 100  80  90 100  90  30
Kellogg        49  38  45  35  43  32 / 100  80  90 100 100  40
Moses Lake     60  36  52  39  48  35 /  70  10  20  80  30  20
Wenatchee      56  38  49  37  45  34 /  90  20  70 100  50  30
Omak           50  33  45  35  45  30 / 100  20  60 100  40  20

&&

.OTX WATCHES/WARNINGS/ADVISORIES...
WA...High Wind Watch from Tuesday evening through Wednesday
     afternoon for Central Chelan County-Lower Garfield and
     Asotin Counties-Moses Lake Area-Northeast Blue Mountains-
     Northeast Mountains-Okanogan Highlands-Spokane Area-Upper
     Columbia Basin-Washington Palouse-Waterville Plateau-
     Wenatchee Area-Western Chelan County.
     Wind Advisory from 1 PM this afternoon to 6 AM PST Tuesday for
     Moses Lake Area-Northeast Blue Mountains-Spokane Area-
     Upper Columbia Basin-Washington Palouse-Waterville
     Plateau.
     Flood Watch through Wednesday morning for Central Chelan
     County-Wenatchee Area-Western Chelan County-Western
     Okanogan County.
     Winter Storm Watch from Tuesday evening through Wednesday
     evening for Western Chelan County.
ID...Flood Watch from Tuesday afternoon through Wednesday afternoon
     for Central Panhandle Mountains-Coeur d`Alene Area-Idaho
     Palouse-Northern Panhandle.
     High Wind Watch from Tuesday evening through Wednesday
     afternoon for Central Panhandle Mountains-Coeur d`Alene
     Area-Idaho Palouse-Lewis and Southern Nez Perce Counties-
     Lewiston Area-Northern Panhandle.
     Wind Advisory from 1 PM this afternoon to 6 AM PST Tuesday for
     Coeur d`Alene Area-Idaho Palouse-Lewis and Southern Nez
     Perce Counties-Lewiston Area.

&&

$$