Gannett, Idaho Weather Forecast Discussion

760
FXUS65 KPIH 090940
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
340 AM MDT Tue Sep 9 2025
.KEY MESSAGES...
- Isolated to scattered showers and thunderstorms much of the
  week.
- Cooling trend, with highs 5 to 10 degrees below climatological
  norms by late week.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 338 AM MDT Tue Sep 9 2025
Low pressure situated along the OR/CA coast today will result in
increased moisture into Southeast Idaho in Southwest flow. Radar
shows showers shifting into central and southeastern Idaho early
this morning. The 24-hour precipitation forecast is 0.10" across the
northern half of the CWA with 0.25" to 0.50" across the central
mountains. Locally higher totals will be possible with stronger or
training storms. HREF probability of thunder indicates a 10 to 30
percent chance of isolated thunderstorms across portions of
Southeast Idaho from just before sunrise to around 1 PM MDT. Chances
from then through the evening increase to 20 to 70 percent across
the central mountains, increasing further north, and 20 to 50
percent chance across the eastern highlands and upper Snake River
Plain. Stronger storms will be capable of producing wind gusts to
around 40 mph and small to moderate hail.
&&
.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 143 PM MDT Mon Sep 8 2025
Unsettled pattern continues through the week, though models have
started to consolidate precipitation mainly over the higher
elevations with less coverage through the Snake Plain. This may be
due to pulling drier air between weak shortwaves rotating around the
upper low. Development and progression of convection throughout the
week will also have significant input to how much QPF falls over any
particular location. As such, long term estimates of the
precipitation should be taken with a dose of skepticism this far
out. Temperatures remain cool, with highs generally in the 70s for
many lower elevation locations. Once the upper trough shifts east
for the weekend, there is still a potential for wrap around showers
to occur especially Saturday. Temperatures remain cool with ensemble
means dropping daytime highs to the mid to upper 60s for portions of
the Snake Plain, and lows generally in the 40s.
&&
.AVIATION /06Z TAFS THROUGH 06Z WEDNESDAY/...
Issued at 1108 PM MDT Mon Sep 8 2025
Watching a shortwave moving north which will arrive late
tonight into tomorrow morning. HRRR and 3km NAM differ on the amount
of convection, with the NAM continuing to show more showers with a
few storms around. Uncertainty as we move through the day on
Tuesday, cloud cover may limit additional storm development in the
afternoon. However, models seem to indicate quite a bit of showers
throughout the day in and around SUN on Tuesday, just a question if
any of those develop into thunderstorms or not.
&&
.FIRE WEATHER...
Issued at 143 PM MDT Mon Sep 8 2025
Dry day continues through this evening in between systems. Next
round of moisture shifts into the region after midnight with showers
developing across the southwest half of the district, shifting
northeast through the day Tuesday. Although chances are low
overnight and early Tuesday, there is potential for a thunderstorm
or two, and chances increase into the afternoon and evening. This is
the beginning of a broad period of unsettled conditions for the
week. Daytime humidities are expected to remain above critical
thresholds throughout the week. Precipitation amounts remain
variable, with the Snake Plain expected to remain the driest overall
compared to higher elevations. Thunderstorm activity could provide
periods of locally heavy rainfall. The deep Pacific trough shifts
east by the weekend, but moisture could linger for continued
isolated to widely scattered showers and thunderstorms both Saturday
and Sunday.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Cropp
LONG TERM...DMH
AVIATION...13
FIRE WEATHER...DMH

NWS PIH Office Area Forecast Discussion