531
FXUS65 KPIH 300752
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
1252 AM MST Sun Nov 30 2025

.KEY MESSAGES...

- Snow lasts through this afternoon.

- Bulk of the precipitation with this round is along the 84/86
  corridor and south into the higher elevations.

- Much colder temperatures remain in place next week with
  another round of snow likely on Tuesday.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 1251 AM MST Sun Nov 30 2025

Snow continues to push south and east across the state this
morning. The bulk of accumulations will occur basically from the
Big Holes to Twin Falls and points south. We will likely
flurries/dusting across most areas of central and eastern Idaho
except a good chunk of the central mountains outside of the
Sawtooths and surrounding areas. We may see up to 1" along the
84/86 corridor. The lower elevations of the South Hills, Albion
Mountains, and southeast highlands should see up to 2", with
2-5" across higher elevations closer to the Utah border. We may
see a brief convergence band set up from Pocatello shifting west
toward Burley before dying out later this afternoon. Any
"enhancement" from this band should be minimal. Impacts to
travel should be pretty limited even for higher passes, although
enough snow could fall over Emigration Summit to create slightly
higher travel issues for a few hours. At the moment, we are
still not looking at anything requiring any type of
statement/headline. The weather will quiet down quite a bit
until Monday night when the next wave arrives from the
northwest. We are likely going to see some stratus and patchy
freezing fog across around tonight and Monday morning. As
expected, very few if any places will top out above 40 this
afternoon and again Monday.

&&

.LONG TERM /TUESDAY THROUGH SATURDAY/...
Issued at 143 PM MST Sat Nov 29 2025

The beginning of the extended period begins with a break on
Monday under influence of transitory ridge. The next system
arrives Monday night and lingers through Wednesday morning.
Model means support an additional inch of snowfall at lower
elevations, and 2-4" across the higher elevations south and east
of the interstates. Beyond Wednesday there is still uncertainty
present in the models. Ensemble clusters favor building a ridge
off the coast, with a couple clusters attempting to develop a
rex block over the western states. This should result in a dry
northwest flow over East Idaho. But the deterministic GFS and
ECMWF both flatten the ridge quickly and introduce fast active
flow into the PacNW by the end of the week into the weekend. The
NBM moderates temperatures slightly for Friday and Saturday,
but maintains weakly unsettled flow with continued chances of
showers mainly over higher elevations.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1048 PM MST Sat Nov 29 2025

Mostly only made minor tweaks and nudges with the 06z TAF update,
except confidence is trending a bit lower on impacts at KSUN and
have trended them a bit more optimistic (MVFR conditions now
confined to a PROB30 group from 09-13z/2-6am Sunday morning instead
of forecast as predominant). Forecast impacts are just really
focusing to the south across the eastern Magic Valley and lower
Snake Plain down to the Utah border (KBYI and perhaps KPIH). Also
continued to evaluate fog and low stratus potential at KIDA Monday
morning...currently feel VCFG/SCT009 type hints/impacts are possible
after about 09z/2am, just beyond the end of the current forecast
period, and overall confidence remains low. Previous aviation
discussion follows below.

Issued at 442 PM MST Sat Nov 29 2025

A shield of BKN high-level clouds is overspreading southeast Idaho
from the northwest as a progressive shortwave trough (weak closed
low at times) approaches the region, but confidence remains high in
VFR conditions and no significant weather impacts to aviation
through 09-11z/2-4am overnight tonight...good news for wrapping up
most of today`s air traffic this evening. Early Sunday morning, have
tweaked/refined timing of a period of snow/snow showers with a re-
review of the HREF suite along with new runs of the NAMNest and
HRRR, with the greatest impacts (MVFR cigs and MVFR to IFR vsbys)
still favoring KBYI and KPIH. KSUN will be right on the edge of the
more organized precipitation but may also see similar conditions. If
organized/persistent -SN materializes for KBYI (as hinted at in some
guidance such as HREF snowfall rates), 1-2SM vsbys will be likely
and we may need to trend that direction in future forecast updates
(when it comes to snow...if it "goes", it really goes as far as
dropping vsbys). Further northeast, confidence is just a touch less
at KPIH (where we continue a PROB30 for similar impacts and at least
predominate -SHSN), and especially drops off at KIDA and KDIJ which
may reside along the northern/eastern edge of ANY snow shower
activity with this system (VCSH and PROB30s here, but it`s possible
cigs/vsbys hold closer to the upper end of MVFR or even VFR if snow
showers avoid the terminals). Precipitation should be done by 19-
20z/noon-1pm Sunday at all TAF terminals (assuming any lingering low
clouds clear out efficiently as advertised by the NBM) with skies
quickly going FEW to SCT, and no further impacts to aviation for the
rest of the afternoon and evening. No guidance favors any winds
exceeding 10kts. Beyond the current TAF period...will need to
further evaluate the potential for at least some nearby fog or low
stratus for KIDA hinted at in HRRR guidance late Sunday night into
Monday morning. Confidence in this is currently very low.

&&

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

&&

$$

SHORT TERM...Keyes
LONG TERM...DMH
AVIATION...01