Groveland, Idaho Weather Forecast Discussion

673
FXUS65 KPIH 261039
AFDPIH
Area Forecast Discussion
National Weather Service Pocatello ID
439 AM MDT Fri Sep 26 2025
.KEY MESSAGES...
- Light showers in the southeast highlands this morning.
- Clouds and wind shift end warming trend. Warming returns
  Saturday.
- Showers and thunderstorms return to the south half Sunday
  morning, afternoon.
&&
.SHORT TERM /THROUGH SUNDAY NIGHT/...
Issued at 1252 AM MDT Fri Sep 26 2025
A weak upper level low brought mainly clouds, along with some
very light precipitation to the southeast highlands of eastern
Idaho. The showers will end this morning, then clearing as
northwest wind develops behind this weak low. This is very
temporary as an stronger upper level low/trough slowly moves in
Sun morning and remains to the end of the period. This will
bring only light showers and thunderstorms to limited areas in
the south during the morning, but will slowly spread northward
during the afternoon, reaching the MT-ID border Sun evening.
The northwest air flow will mean cooler temperatures for today.
Warming returns for most locations under the clear skies on
Sat, although not to the warmth of Thu. The incoming trough will
bring clouds and cooler temperatures aloft to some locations on
Sun.
The upper level wind is stronger as the overall weather pattern
shifts southward, and so wind should be stronger than it has
been lately. As the trough approaches Sat night and Sun, wind
will shift back to south to southwest.
&&
.LONG TERM /MONDAY THROUGH THURSDAY/...
Issued at 1252 AM MDT Fri Sep 26 2025
The upper level trough lingers over the forecast area in nearly
all clusters through Wed afternoon. The clusters bring back
either flat zonal flow or some upper level ridging to the east
that allows for some southwest flow aloft. Precipitation and
thunderstorm threat decreases considerably Wed night with drier
conditions for Thu.
Temperatures cool strongly for Mon, by 8 to 12 deg F, then
another 3 to 8 deg F behind this low as it passes to the east on
Tue/Wed. This puts Snake River plain temperatures in the 60s for
highs, but the cloud cover keeps overnight lows mild and away
from Frost or Freeze threat until Wed night.
Despite the trough, wind does not get significantly higher with
gusts maybe into the 20s, maybe slightly higher on high
elevation ridges.
&&
.AVIATION /12Z TAFS THROUGH 12Z SATURDAY/...
Issued at 433 AM MDT Fri Sep 26 2025
The southeast corner of the state wound up receiving
measureable rainfall at KPIH, but this should clear out during
the morning hours. CIGs are BKN-OVC100-110 at KPIH and KDIJ,
but by 26/16Z to 26/18Z should be SKC-SCT with all airdromes
going to SKC by 26/20Z. KSUN is already SKC. Wind is stronger
than it has been in a week, with 15KT already going on or
developing later this morning everywhere. Even KSUN should get
this strong by late morning. Wind should decrease strongly in
the early evening, around 27/01Z or so. VSBY should remain P6SM
everywhere.
&&
.FIRE WEATHER...
Issued at 1252 AM MDT Fri Sep 26 2025
Cooler temperatures today behind the weak trough that did
actually bring some light rain to portions of the Caribou NF and
nearby BLM lands. The cooling northwest flow will shift back to
south and southwest flow by Sat, and so warming and drying
returns for a day. The shift in wind is caused by an approaching
low, that starts to bring showers and thunderstorms during the
morning in the south on Sun, spreading to the MT border region
by Sun night. Humidity should spike upward with this event, and
temperatures will cool by Tue some 15 to 20 degrees compared to
the high temperatures observed last Thu. Some gusty wind but
nothing reaching significant levels, and humidity will stay
high, away from critical levels.
&&
.PIH WATCHES/WARNINGS/ADVISORIES...
None.
&&
$$
SHORT TERM...Messick
LONG TERM...Messick
AVIATION...Messick
FIRE WEATHER...Messick

NWS PIH Office Area Forecast Discussion