Franklin, Idaho Weather Forecast Discussion

134
FXUS65 KPIH 091150
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
550 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 /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 549 AM MDT Tue Sep 9 2025
Showers will increase in coverage throughout the day. Probability of
lightning is less than 10 percent at KPIH, KIDA, and KBYI and
therefore have continued the VCSH at the aforementioned terminals
through 17z-19z. Probability of lightning is greatest at KDIJ, 40 to
60 percent chance. Have included -SHRA at KSUN and KDIJ and PROB30s
for thunderstorms between 20z and 02z. Winds will remain fairly
light outside of storms, with storms capable of gusts to around 35
kts.
&&
.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...Cropp
FIRE WEATHER...DMH

NWS PIH Office Area Forecast Discussion