981
FXUS65 KPIH 052239
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
439 PM MDT Tue May 5 2026

.KEY MESSAGES...

- Breezy Post-Frontal Winds: Gusty down-valley winds in the
  2535 mph range continue behind a backdoor cold front
  necessitating a Lake Wind Advisory for the American Falls
  Reservoir through this evening.

- Frost and Freeze Concerns: A Freeze Warning and Frost
  Advisory remain in effect for early Wednesday

- Dramatic Warming Trend: After a seasonal start in the short
  term, temperatures will soar into the 80s by early next week
  roughly 20 degrees above seasonal normals.

&&

.DISCUSSION...
Issued at 133 PM MDT Tue May 5 2026

Afternoon satellite imagery reveals skies beginning to clear
across the region, with only a few lingering fair-weather
cumulus clouds over the eastern highlands. In the wake of a
recent backdoor cold front, breezy down-valley winds continue to
funnel through the Snake Plain, with observed gusts frequently
reaching the 2535 mph range. These elevated winds will persist
long enough to require the continuation of the Lake Wind
Advisory for the American Falls Reservoir through the short
term. Aside from some isolated shower chances focused near the
Utah border this evening, dry conditions will prevail for the
remainder of the day.

The primary immediate concern is the cold overnight
temperatures expected tonight. A Freeze Warning continues for
the Snake Plain and into the Arco Desert, where a light freeze
is anticipated. Additionally, a Frost Advisory remains in place;
while a widespread freeze is not expected within the advisory
area, more rural sections could briefly flirt with the freezing
mark before sunrise.

Following this cool start, daytime temperatures on Wednesday
will stay near seasonal norms in the 60s. A transition to a much
warmer pattern begins Thursday and Friday as a ridge of high
pressure builds. This trend will be briefly interrupted Friday
night into Saturday by a potent, fast-moving system passing to
our north. While this feature will likely increase cloud cover
and wind speeds across Eastern Idaho, it is not expected to
produce significant precipitation.

In the wake of that passing disturbance, strong high pressure
will anchor itself over the Intermountain West for the weekend
and into early next week. This will result in mostly sunny and
dry conditions with temperatures climbing well above average.
Current forecast models suggest lower valleys will reach the 80s
to start next week, with some mid-to-upper 80s possible. These
values would be approximately 20 degrees above normal for early
May. While some long-range details regarding the exact magnitude
of the heat still need to be refined, the overall outlook for
the week ahead remains warm and predominantly dry.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 433 PM MDT Tue May 5 2026

Expect VFR conditions throughout the period. In the meantime,
have kept PROB30s at KPIH, KIDA, and KBYI to account for some
residual showers working through later this afternoon into the
early evening. Winds will remain breezy, with gusts around 15 to
25 kts, through early this evening. Then expect variable winds
at 6kts for all sites by around midnight with clear skies. Winds
becoming slightly breezy by tomorrow afternoon, 10 to 15kts.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Frost Advisory from 3 AM to 9 AM MDT Wednesday for IDZ051-055.
Freeze Warning from 3 AM to 9 AM MDT Wednesday for IDZ052>054.

&&

$$

DISCUSSION...McKaughan
AVIATION...TW