892
FXUS65 KPIH 041808
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
1108 AM MST Thu Dec 4 2025

.KEY MESSAGES...

- Moderate to heavy mountain snow starts this afternoon,
  continues through Saturday morning. Winter Storm Watch in
  effect.

- Light snow today and tonight for the Snake River plain,
  changing to rain for Friday and Friday night.

- Windy to very windy Friday evening through Saturday in the
  Snake River plain, southern highlands.

&&

.SHORT TERM /THROUGH SATURDAY NIGHT/...
Issued at 201 AM MST Thu Dec 4 2025

Upper level northwesterly flow will bring a winter storm through
the northern Rockies and central/eastern Idaho starting this
afternoon and continuing through Tonight/Fri/Fri Night/Sat
morning. Peak rain and snow occur Fri afternoon and evening.
Snow level starts out low and rises on Fri to leave the snow
above 5500ft elevation during the day and 5000ft elevation at
night, though slightly higher along the Utah border.

Except for the Bear Lake basin zone, all Utah border regions
will likely verify a Warning due to snow. Along the Wyoming
border region, the Big Holes and Caribou mountains are also
likely to be Warning level. All the rest should be Advisory.

Probable additions in the central Idaho mountains for Advisory-
level snowfall includes all zones at Advisory level. Only the
Sawtooth/Stanley basin zone could challenge the Warning level of
snowfall.

Temperatures will start a warming trend for the highs, with
widespread temperatures getting above 40 degrees on Sat in
nearly the entire Snake River plain/eastern Magic Valley. It
should be similar for the lower elevations in the southern
highlands. Overnight lows will warm the next two nights, but on
Sat night temperatures will cool behind this winter storm.

Wind is still expected to increase with this storm on Fri,
peaking on Sat. Wind Advisory could be needed for the Snake
River plain.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
Issued at 201 AM MST Thu Dec 4 2025

The upper level ridging intensifies, and this is brought out by
how warm the lower elevations are expected to get. The Pocatello
airport may see temperatures around 50 deg F by Tue. The warmth
is not record-breaking, and even features clouds and
precipitation, making for sloppy rain and snow in the mountains
with rain at the Snake River plain elevations through this
period, save Sun night. And there are solid risks of
precipitation each period through Wed afternoon. Wind is
expected to stay elevated at a minimum and possibly Advisory or
Warning criteria for the shortwave moving through on Tue and
Wed (especially Wed).

&&

.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 1100 AM MST Thu Dec 4 2025

BKN/OVC CIGs in the 1500-3500 ft range continue across eastern
Idaho terminals with the exception of KSUN which continues to be
on the far northern edge of some lower CIGs in the valley just
south of the airport. Expecting the upcoming TAF period to be
challenging with widespread low clouds and snow expected as our
next weather system moves through the region. KBYI, KPIH and
perhaps KSUN will likely see a transition from snow to a mix or
even all rain at some point while some warmer air moves into the
area from the south. Precip type confidence is lower than
desired but confidence is much higher with regards to prolonged
MVFR/IFR CIGs through much of the period. Winds will increase a
bit too during the period with 15-25 kt gusts possible in the
valley terminals.


&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Winter Storm Watch from 5 PM MST this afternoon through late
Friday night for IDZ058>066.

&&

$$

SHORT TERM...Messick
LONG TERM...Messick
AVIATION...McKaughan