Lewiston, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

848
FXUS66 KOTX 141213
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
413 AM PST Sat Feb 14 2026

.KEY MESSAGES...

- Light snow to impact the mountain passes this weekend.

- Unsettled weather pattern next week. A mix of rain and wet
  snow for valleys early next week becoming colder with snow at
  times in the valleys by mid week into next weekend.

&&

.SYNOPSIS...
A more active weather pattern returns this weekend, with
mountain snow and a mix of rain and snow in the valleys. Falling
snow levels and colder temperatures will bring the potential
for light lowland snow accumulations next week.

&&

.DISCUSSION...
Saturday-Monday: A pattern change is underway and over the next
few days, precipitation will impact communities across the
Inland NW at different times. Generally speaking, impacts will
come in the form of mountain snow and winter travel conditions
over the passes and largely rain or wet, non accumulating snow
in the lowlands. There will be some exceptions to the later that
we will discuss in a bit. The general weather pattern features
a broad trough off the coast, flat ridging inland allowing
moisture to stream inland in a southwest to northeast fashion.
Forcing is weak with a diffuse frontal boundary such that the
highest probabilities for a 0.25" or more QPF will focus where
orographics play a larger role (Cascade Crest and Idaho
Panhandle with some bleed over into the Selkirks of far NE WA).
The axis of precipitation currently impacting the Cascades, E WA
and N ID will taper off Saturday morning courtesy of a weak
shortwave passing through and ejecting into Canada. A few
showers will linger over Idaho and southeastern WA through
midday but focus will shift toward a developing warm front and
steady precipitation returning to southeastern WA and north-
central Idaho Saturday late afternoon and continuing into Sunday
morning. The Central Panhandle Mountains will take a brunt of
this secondary surge of precipitation with a 50% chance for >4"
of snow at Lookout Pass. Snow levels across SE WA and NC Idaho
during this time will waver between 3000-4000 feet.

The large scale pattern begins to buckle Sunday night into Monday
as the offshore trough receives a reinforcing shot of cooler
air from the Gulf of AK and takes on a more meridional
orientation. This will result in increasing southerly flow over
the INW and the axis of heavier precipitation will take on a
south to north orientation. There is moderate uncertainty
heading into this period of the focus exactly where this
meridional moisture axis will setup. Some solutions place this
over the Cascades and central WA while others in North Idaho/E
WA. Many things are ongoing in the atmosphere including cooling
aloft, warming in the low elevations, especially southeastern WA
and North Idaho, weaker waves ejecting inland from the
southwest, and cyclogenesis at the surface. The orientation of
the flow (S/SE) is very favorable for trapping antecedent cool
air into the E Slopes and Okanogan Country so if the
precipitation band sets up in these areas, appreciable snow will
be possible for the mountains and even for some lowlands. If
this sets up further east, the cooler air will still be there
but far less moisture to work with. Appreciable snows will setup
over the Selkirks of NE WA and N ID with mainly rain for the
lowlands. Given the spread, NBM PoPs are very spread out with
50-70% chances and I would be prepared for these to become
narrowed down and dialed in to less areas in the coming days. It
is quite the dynamic situation setting up. Temperatures on
Monday come with large ranges for SE WA and the lower Idaho
Panhandle. If the precipitation sets up further west, locations
like Lewiston could be in the mid 50s with mid 40s as far north
as Spokane. If the clouds and precipitation is further east,
these readings could on the order of 10 degrees cooler. Central
and northern WA have less spread with highs more likely to
reside in the 30s.

Monday night through Thursday: Conditions will take a turn toward
winter with a 90% chance for a cooler trough to migrate through
the region. The first shot of cooler air and lowering of snow
levels will arrive Tuesday morning and the air mass will
continue to cool 1-2C each day thereafter through Thursday. The
chances for lowland snow will increase each day most areas
outside the deep Basin and L-C Valley looking at a 20-40% chance
for 1" snow or more each Wednesday and Thursday. It is tough to
say how organized any snow will be given the convective nature
of the precipitation, low skill for modeling weaker embedded
waves this far out, and still moderate spread where these waves
will track. We do have confidence that 500mb temperatures will
be on the order of -30C or colder and these patterns this time
of year have a history of producing bands of convective snow
showers, some which could be locally heavy at times. We are also
at the time of year where if this falls at night/early morning,
lowlands have a strong possibility of coping with winter travel
conditions. Periods of snow will undoubtedly impact the
mountains and mountain passes creating winter travel conditions.

Snow showers will linger into Friday, particularly in the Idaho
Panhandle with intensities decreasing in Central/Eastern WA as
the trough begins to migrate eastward and moderate some. By the
weekend, ensemble diverge with 70% of the members showing
moderating temperatures and return toward west to southwest
flow. The remaining 30% drop another cold trough into the region
with organized bands of snow. Very little confidence in the
forecast details by this point. Generally speaking, both
scenarios indicate a continuation of precipitation chances and
even if the air mass were to moderate as in scenario one, the
antecedent air mass will start off cold with p-types favoring
snow before transitioning to rain. In scenario two, we will be
talking mainly snow showers again. Stay tuned /sb

&&

.AVIATION...
12Z TAFS: BAnd of showers has shifted over the Idaho Panhandle.
Low stratus will continue through the morning and slowly break
up by the afternoon between 19-20z (70% chance). Clearing
around MWH and EPH will bring periods of fog and low cigs. Another
round of -RA will spread into PUW- LWS after 20Z lasting into
the night. This will bring a 70% chance for lowering cigs of
MVFR or lower at PUW and 30% chance at LWS. GEG-SFF-COE will be
on the northern periphery of the second axis of rain. Rain
chances increase through the overnight hours for these
locations. Little to no rain is expected to reach north-
central WA during this time leading to another challenging
forecast for low stratus and fog. /JDC

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS:
General consensus amongst the models are for most terminals to
trend toward VFR Saturday afternoon though confidence in timing
is low. Moderate confidence for cigs to lower after 20z PUW-LWS
as steady rains return. Low confidence this will manifest into
MVFR or lower restrictions for LWS. Moderate confidence for
MVFR conditions for GEG-SFF-COE-MHW after 06Z.

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

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        43  34  42  33  42  33 /  40  40  20  20  60  60
Coeur d`Alene  43  33  41  32  43  33 /  70  60  40  20  60  60
Pullman        43  37  42  35  45  33 /  70  90  60  20  60  70
Lewiston       47  39  48  36  50  37 /  60  80  50  20  40  60
Colville       43  29  42  30  41  33 /  40  10  10  20  60  60
Sandpoint      40  32  39  30  40  33 /  90  40  40  30  70  70
Kellogg        41  35  40  33  43  34 /  90  80  70  40  70  70
Moses Lake     45  32  46  32  42  32 /  10  20  10  10  60  40
Wenatchee      44  32  43  31  38  31 /  10  10  10  10  50  40
Omak           44  29  42  30  40  33 /  10   0   0   0  50  40

&&

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

&&

$$