Rupert, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

204
FXUS65 KPIH 012344
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
444 PM MST Sun Feb 1 2026

.KEY MESSAGES...

- After a brief relative cooldown Monday and Tuesday, the dry
  and warming trend returns through the end of the week.

- Inversions may break provided there is sufficient mixing
  Monday and Tuesday, but stagnant conditions will return for
  the latter half of the week.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 144 PM MST Sun Feb 1 2026

Satellite imagery shows upper ridge axis over East Idaho
flattening ahead of shortwave feature moving through Oregon
today. Moisture moving into the region is continuing to produce
cloud cover over Idaho, but not sufficient to produce any
precipitation today. The shortwave shifts across the panhandle
tonight and through western Montana on Monday. Short range
ensembles and NBM means remain very dry, but the very high end
probabilistic data does produce a few hundredths of liquid
precipitation across a few higher elevation regions. There is an
extremely low chance (less than 10%) of a few places seeing 1"
of snow accumulation, mainly back-country ridges north of the
Sawtooths Monday and along the Continental Divide and
Yellowstone regions through Monday night. For the majority of
East Idaho, the primary impact will be a slight dip in daytime
highs and a slight increase in afternoon winds.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 144 PM MST Sun Feb 1 2026

Second shortwave drops through northwest flow Monday night into
Tuesday, grazing the northeast portions of the forecast area.
Much like the Monday system, this one also contains little to no
moisture for most of the region. Similarly, the probability of
producing any snow accumulations more than a dusting are around
or less than 10%, and the forecast remains dry. For the
remainder of the work week, the ridge rebounds over the region,
returning East Idaho to a warming trend and potential stagnant
air mass. There is a hint of a potential change arriving by late
in the weekend. Ensemble and clusters hint at a pattern change
by late weekend as a deep Pacific trough moves inland and the
upper ridge shifts east. Current ensemble clusters show
significant spread regarding the details of this transition,
particularly given the amplified blocking pattern over the
Western U.S. The NBM introduces light precipitation late Sunday
at the end of the forecast period. Are we confident on this? Not
at all. Highly amplified blocking patterns can be hard to break
down, and models can be too aggressive in doing so especially
this far out in time. But it will be worth keeping on eye on
this week.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 435 PM MST Sun Feb 1 2026

A weak short wave is moving thorugh the area early this evening
into tomorrow, Monday, morning. Expect a slight increase in
winds, still under 10 knots. Also, look for mid level clouds
this evening. Models are still showing a very low chance of
MVFR CIGS over IDA, PIH, and DIJ by early tomorrow morning.
Have kept the SCT030 CIGS. Expect overall clearing and overall
weak southwest winds for most sites tomorrow afternoon. Model
guidance is showing a northerly wind shift for KIDA for 3 to 5
hours by mid tomorrow morning and continuing into early to mid
afternoon tomorrow. Just put variable at 6 knots for IDA for
now. High pressure starts building back in by tomorrow afternoon
and continues to get stronger into Tuesday. &&

.AIR QUALITY...
Issued at 144 PM MST Sun Feb 1 2026

The ridge of high pressure over East Idaho is beginning to
flatten slightly under the influence of an encroaching shortwave
feature over Oregon, with another shortwave feature expected for
Tuesday. These features should be enough to mix out the lower
atmosphere, limiting the surface-based inversions and increasing
winds slightly for both days. By Wednesday, the upper ridge is
forecast to shift across East Idaho once again, returning the
potential for stagnant air mass through the end of the week.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Air Stagnation Advisory until noon MST Monday for IDZ054-059.

&&

$$

SHORT TERM...DMH
LONG TERM...DMH
AVIATION...TW
AIR QUALITY...DMH