Clayton, Idaho Weather Forecast Discussion

914
FXUS65 KPIH 050426
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
1026 PM MDT Thu Sep 4 2025
.KEY MESSAGES...
- A slow cooldown begins today
- Isolated dry thunderstorms expected today and tomorrow
- Coverage for showers and thunderstorms still increases over
  the weekend
&&
.SHORT TERM /THROUGH FRIDAY/...
Issued at 128 PM MDT Thu Sep 4 2025
Limited monsoon moisture remains over central and eastern
Idaho until the weekend. Higher resolution models continue to
show a few spots where we will keep isolated storms in the
forecast through the period. Through this evening, we have that
going across the central mountains and out across the Snake
Plain into the bench areas of the Upper Snake Plain. This looks
like a combination of storms forming over the mountains,
potential outflow off those storms, and a convergence/frontal
band dropping southwest from Montana. Another area of potential
development is along the Utah border from near Malta to Bear
Lake. Again, the chance is low (isolated) with little or no rain
expected. The chance of seeing strong wind gusts (over 35 mph)
is 10-30% where we storms fire off. Overnight and Friday
morning, a few showers may linger especially around Bear Lake
but the chance is under 15%. For tomorrow and tomorrow night,
the potential is a little less as a bit drier air lingers across
the area and northerly flow pushing better chances south and
west of here. A few storms are possible mainly between the Wood
River Valley and the Lost River Range, and along the Utah
border. There continues to be some fluctuation on any chance of
storms tomorrow, so we may see that ebb and flow a bit in the
next 24 hours. Again, little rainfall and a 10-20% chance of
gusts over 35 mph. Temperatures will continue to slowly drop in
the next 36 hours. Highs tomorrow will be in the low/mid 80s
across lower elevations, with an overall drop everywhere of 3-6
degrees from today.
&&
.LONG TERM /FRIDAY NIGHT THROUGH THURSDAY/...
Issued at 129 PM MDT Thu Sep 4 2025
Models remain consistent in bringing a solid push of moisture across
East Idaho for the weekend as a pair of shortwaves push the ridge
axis to the east. Isolated to scattered showers and thunderstorms
are expected both Saturday and Sunday, along with a decrease in
daytime high temperatures. As far as QPF goes, NBM probabilistic data
keeps the better chances for wetting rains for Sunday afternoon and
evening. For Saturday there is roughly a 10-20% chance of at least a
0.10 across the central mountains and southern highlands. Sunday
that spreads across more of the region, but probabilities reach
their highest at 35-45% across the northern regions near the Divide.
Despite the southwest flow continuing, there looks to be a little
bit of a break in the moisture for early next week, with shower and
thunderstorm chances decreasing to isolated for higher elevations
Monday. Deeper moisture returns as early as Tuesday, with scattered
thunderstorms each day through the remainder of the forecast.
Temperatures drop to the 70s with this second increase in
moisture.
&&
.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1021 PM MDT Thu Sep 4 2025
Widespread VFR conditions will continue through Friday night.
Not expecting significant thunderstorm coverage Friday afternoon
and have none in any TAFs tonight. Winds will become downslope
Friday morning through the day with north to northeast expected
at PIH, IDA and BYI by Friday. Speeds still generally under 10
knots through Friday night.
&&
.FIRE WEATHER...
Issued at 129 PM MDT Thu Sep 4 2025
Isolated mainly dry thunderstorms are still expected this afternoon
and evening, generally over the central mountains. High resolution
models kick some of the activity out into the northern portions of
the Snake Plain this evening, generally north of US-20, followed by
pushing a northerly down-valley gradient overnight through the
region. Thunderstorm chances decrease for Friday, but return for the
weekend, with the greatest chances of wetting rains Sunday afternoon
and evening close to the Montana border. There is a break in the
pattern early next week, followed by a return of an increasing
threat of showers and thunderstorms for Tuesday through Thursday.
Daytime high temperatures gradually cool into the 70s by midweek
next week, with the driest afternoon humidities today.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Keyes
LONG TERM...DMH
AVIATION...GK
FIRE WEATHER...DMH

NWS PIH Office Area Forecast Discussion