Ammon, Idaho 7 Day Weather Forecast

Wx Forecast - Wx Discussion - Wx Aviation

339
FXUS65 KPIH 152310
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
510 PM MDT Fri May 15 2026

.KEY MESSAGES...

- Another Drastic Temperature Swing Coming: Afternoon highs
  have plummeted 20+ degrees since Wednesday, and another sharp
  drop is expected Sunday as temperatures struggle to reach the
  mid-40s to lower 50s.

- Breezy Conditions and Lake Wind Impacts: Lake Wind Advisory
  for the American Falls Reservoir due to sustained west winds
  up to 25 mph and gusts to 35 mph and Wind Advisory for the
  Upper Snake and Arco Desert

- Frost and Freeze Risk: Winter-like conditions return late
  this weekend, with frost or freeze products likely needed for
  growing zones Sunday through Tuesday morning.

&&

.DISCUSSION...
Issued at 115 PM MDT Fri May 15 2026

Afternoon satellite imagery is once again void of much appreciable
cloud cover. Only a few mid/high level clouds can be seen and
these are pretty isolated. Nearly seasonal temps continue this
afternoon despite the clearer skies with breezy west-to-
southwest winds of 1525 mph continuing along with higher gusts
which will remain in place through the evening. Lake Wind/Wind
Advisories continue accordingly because of the winds with
another likely needed for Saturday as winds look very similar to
today.

A significant pattern shift arrives this weekend as a potent
trough digs into the Pacific Northwest. While cloud cover
increases overnight tonight and into Saturday, the bulk of the
precipitation should hold off until Sunday or Monday. Sunday
will mark the coldest point of the transition, with highs in the
mid-40s to lower 50s  a shocking change from just a few days
ago. This system will likely bring light snow to the central
mountains and eastern highlands, and while a few flakes could
drift into the Snake Plain, significant impacts there are
unlikely. Some light accumulations across the higher terrain
certainly seems likely. Temperatures will stay below seasonal
averages until mid-to-late next week as the trough slowly exits
the area with temps not likely to return to seasonal levels
until Wednesday at the earliest. Late next week and into next
weekend looks like an opportunity for temps to climb to above
normal levels once again but this is still far out in time.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 505 PM MDT Fri May 15 2026

Stronger winds should begin to diminish by mid evening. We will
start seeing an increase in clouds in the next 24 hours, but
even at this point nothing is expected to drop below VFR at any
TAF site. Most of the precipitation remains north of even SUN
and DIJ based on the latest trends. Winds do increase again mid
to late morning for all TAF sites. Gusts of 15-30kts are
forecast. Of note, we may see a shorter wind of southerly winds
at SUN tomorrow afternoon. This pattern tends to favor a switch
to a westerly wind with some gusts, and an earlier switch to
northwest. At this point, when the wind switches to northwest,
expect a decent headwind trying to land.

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
Wind Advisory until 9 PM MDT this evening for IDZ052-053.

&&

$$

DISCUSSION...McKaughan
AVIATION...Keyes