238
FXUS66 KOTX 081749
AFDOTX

Area Forecast Discussion
National Weather Service Spokane WA
949 AM PST Wed Jan 8 2025

.SYNOPSIS...
A quick moving disturbance will bring light wintry precipitation
to the Inland Northwest this morning. Thursday will be a dry and
cloudy day. Another chance for wintry precipitation is expected on
Friday with the passage of a frontal system. Saturday and possibly
Sunday have a good chance of being sunny across central and parts
of eastern Washington.

&&

.DISCUSSION...

At 345 AM, a Winter Weather Advisory was issued for the Spokane
and Coeur d`Alene area for localized accumulations of 1 to 2
inches mainly north of I-90. Radar indicated a west to east band
of moderate snow across the northern metro prompting the Advisory.
The fast moving disturbance will be clear of the metro by 6 AM,
but the Advisory was issued through 8 AM for locally treacherous
conditions for the morning commute. And as mentioned in the
previous discussion below there will be a small chance of freezing
drizzle behind the main band of snow. We will know by 8 AM if the
drizzle will come to fruition and worthy of extending the advisory
for another couple of hours. /GKoch

.PREVIOUS DISCUSSION...

Today: An upper level disturbance will bring the Inland Northwest
a quick shot of precipitation this morning. As of 230 AM, radar
trends over central Washington are more impressive than
anticipated. The evening runs of the NAM and ECMWF trended toward
more precipitation with this quick hitter. The system is moving
fast enough that most places across eastern Washington and north
Idaho won`t experience more than an hour or two of snow. Most
places will get less than an inch, but with some convective
enhancement a few spots mainly north of I-90 in Washington or over
the mountains of north Idaho could get an inch or two before this
band of showers clears north Idaho by 8 AM. A chance of freezing
drizzle has been included over the Spokane area, West Plains, and
Palouse this morning following the band of snow. This is not a
high confidence forecast, but model sounding from the NAM suggest
enough moisture injected into the low levels from the
precipitation this morning along with low stratus from the
Columbia Basin pushed upslope to warrant the mention of drizzle
through mid morning. With early morning temperatures in the low
30s, any icing on roads or sidewalks won`t be around longer than a
couple of hours after sunrise. Afternoon highs will climb into the
30s. We are not overly optimistic about experiencing much sun this
afternoon across central Washington, the Columbia Basin, Spokane
area, or the Idaho Panhandle. Boundary layer winds will be weak
today and the disturbance this morning won`t be strong enough
break our inversion.

Tonight and Thursday: High pressure will rebound overnight into
Thursday. Spots that do experience some clearing this evening will
have the potential to cool quickly. For the rest of us, overnight
lows are expected to be in the upper 20s and low 30s. Thursday
will be dry under widespread low to mid-level clouds. Easterly
surface winds over the southern and central Panhandle, Palouse,
and L-C Valley should erode the low cloud deck helping Lewiston,
Pullman, and St Maries to climb into the mid 30s to near 40.

Friday and Friday Night: The arrival of a cold front on Friday
will bring several inches of snow to the Cascades as well as the
mountains of the Idaho Panhandle and far northeast Washington.
Look for accumulating snow over the Cascades as early as Friday
morning while the Panhandle will experience it`s most significant
accumulations during the afternoon and evening. Snow levels will
be as low as the valleys with places like Sandpoint, Kellogg, and
Clarkia having a 30 to 50 percent chance of an inch of
accumulation according to the National Blend of Models (NBM).
Stevens Pass in the Cascades above Leavenworth and Lookout Pass on
I-90 at the ID/MT border will likely receive 4 to 7 inches by
Friday evening. /GKoch

Saturday through Tuesday: The extended period looks largely dry
across central and eastern WA under northerly flow with a ridge
setting up to our west. However, enough moisture and instability may
remain to allow for periodic light showers across the Cascades as
well as the mountains of northern Idaho. Otherwise, afternoon temps
look to not stray too far from daily norms. Overnight lows will
likely cool to some of our chilliest readings thus far in what has
been a milder than normal winter. Winds to be generally light and
areas of fog/low stratus are likely to persist. /KD

&&

.AVIATION...
18Z TAFS: Moist upslope flow will likely result in ceilings below
1500 feet through the TAF period for most sites with the exception
of LWS which should remain above 2k ft.

FORECAST CONFIDENCE AND/OR ALTERNATE SCENARIOS: High confidence of
continued IFR ceilings through the TAF period with moderate
confidence of degradations to LIFR ceilings and visibilities
tonight into tomorrow morning.

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

Confidence descriptors:
Low - Less than a 30 percent chance
Moderate - 30 to 70 percent chance
High - Greater than a 70 percent chance

&&

.PRELIMINARY POINT TEMPS/POPS...
Spokane        35  28  33  28  33  27 /  30   0   0   0  40  20
Coeur d`Alene  35  26  33  27  35  27 /  30   0   0   0  60  30
Pullman        37  27  36  29  36  30 /  20   0   0   0  70  50
Lewiston       42  31  41  33  43  34 /  20   0   0   0  50  50
Colville       34  26  32  26  33  22 /  20   0   0   0  50  10
Sandpoint      35  27  31  27  32  28 /  40   0   0   0  90  30
Kellogg        36  28  35  28  36  29 /  50   0   0   0  90  60
Moses Lake     37  30  36  31  38  26 /   0   0   0   0  10   0
Wenatchee      36  29  33  29  40  32 /   0   0   0   0  30  10
Omak           34  26  33  27  37  25 /   0   0   0   0  20   0

&&

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

$$