965
FXUS65 KPIH 092015
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
115 PM MST Tue Dec 9 2025

.KEY MESSAGES...

- Abnormally warm temperatures will continue

- Rain and snow shifts north tonight and Wednesday

- Breezy to windy conditions will persist

&&

.SHORT TERM /THROUGH WEDNESDAY NIGHT/...
Issued at 1236 PM MST Tue Dec 9 2025

For some folks, it is wet and windy this afternoon. For many, it
is just windy. There hasn`t been much of any rain across the
Snake Plain and Magic Valley today, and that trend will continue
until everything shifts north of us tonight and tomorrow. That
said, we are seeing light rain pushing through the Treasure
Valley that should move across the Magic Valley and as far east
as Craters and Pocatello. There are some spots hitting WIND
ADVISORY criteria as the winds are peaking with this round of
stronger wind. However, we aren`t seeing widespread conditions
hitting threshold...so we are going to be issuing any headline
at the moment. Looking at wind tonight and Wednesday, we should
see them drop off a little bit this evening...but pick up again
later tonight and tomorrow. We could see a few spots again
hitting advisory thresholds, but nothing that is worthy of
issuing a headline. In reality, while it will remain pretty
breezy out there...overall wind speeds should be a bit lower
that today. Meanwhile, plenty of moisture is falling across the
central mountains. We are seeing a lull across the rest of the
highlands for now. The trends show the next surge arriving late
this evening continuing into tomorrow morning. There are two
issues here to watch. The first is a brief surge of colder air
crossing into Idaho for a few hours. Right now, we have snow
levels with this push down to 6000-7000ft in the Challis and
Pahsimeroi Valleys. We also expect snow levels to drop down
between 5000-6000ft from Island Park and Monida into the far
north end of the Snake Plain. Probability forecasts for snow
levels drop them another 500-1000ft in those areas. This will
produce 1-4" of snow in the Island Park area and around Monida
Pass, with higher amounts well up into the backcountry. If they
drop lower we could see another inch or so of snow in those
areas, and maybe at least snowflakes falling north of the INL
and toward Dubois. The rest of the area by sunrise will see snow
levels rapidly increasing by sunrise...between 8000-9500ft and
eventually all locations during the day tomorrow. The overall
pattern is not much in the way of moisture accumulations except
for the Sawtooths, Frank Church, the eastern highlands and Bear
River Range. In those areas, we should see additional amounts up
to 0.70" in the mountains and up to 0.40" down low. There is a
30-70% chance of more than 0.70" for the highest elevations
around Island Park and the Big Holes. For the Sawtooths and
Frank Church, there is a 45-75% chance exceeding that threshold.
The models so far seem to be overforecasting amounts that far
south in the central mountains, so we feel more confident in
amounts under 0.70" even with fairly strong upslope conditions.
The other trend is how quickly precipitation shifts northeast
after midnight. Some of the models have the main push already
back into western Montana and northern Idaho by sunrise, while
some also hold it longer over central and eastern Idaho. Even if
it holds a bit longer in our area, it will rapidly be out of
here tomorrow evening.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Issued at 1236 PM MST Tue Dec 9 2025

Once again the long term period Thursday through next Tuesday is
dominated by extremely warm and mainly dry conditions.  High
temperatures for the most part will range from the upper 30s to mid
40s mountains and upper 40s to mid 50s lower elevations.  Thursday
and Friday will be the warmest with some upper 50s in the low
elevations.  Lows generally 20s and 30s throughout.  The general
average forecast through the period is around 15 to as much
as 20 degrees above normal.   Upper ridge slides west to east
Thursday through Saturday and will be overhead Saturday.  Will see
only slight cooling when the ridge moves east Sunday through
Tuesday.  Will have mainly dry conditions Thursday through Sunday
with only a slight chance of mountain showers.  A more zonal pattern
may allow a better chance of precipiation  Monday into Tuesday as a
return to Pacific moisture is in play.  Have some chances everywhere
by Tuesday with still very elevated snow levels at over 6 thousand
feet.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 1028 AM MST Tue Dec 9 2025

High winds expected at PIH, IDA and BYI with sustained 15 to 25
knots and gusts 30 to 40 knots through the afternoon and
subsiding a bit after sunset. Not expecting precipitation but
have vicinity showers and VFR ceilings. But did drop IDA to MVFR
after 06Z this evening. Lowest ceilings and best precipitation
chances at DIJ. Kept MVFR ceilings at DIJ with rain showers
through tonight. Dropped ceilings down to 1 thousand feet after
10Z Wednesday morning. Kept SUN VFR as well with only vicinity
showers.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

SHORT TERM...Keyes
LONG TERM...GK
AVIATION...GK