970
FXUS65 KPIH 111122
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
522 AM MDT Mon May 11 2026

.KEY MESSAGES...

- Record or near record highs possible through Wednesday with
  afternoon temperatures 20-25 degrees ABOVE AVERAGE

- A few showers possible near Island Park today, otherwise dry
  until Wednesday afternoon

- Breezy conditions expected today and Wednesday

&&

.DISCUSSION...
Issued at 254 AM MDT Mon May 11 2026

The main story for the first half of the this week will be well-
above normal warmth with the potential to break record highs by
Wednesday. With climatological norms running mid- to upper-60s for
our valley locations, temperatures over the next several days will
run 20 or more degrees above normal. A weak wave will pass to our
north today, flattening the ridge of high pressure that is
dominating our weather pattern. Even still, daytime temperatures
will warm by several degrees as compared to yesterday. HREF members
show isolated to scattered showers north of Rexburg late this
afternoon through late evening. Isolated thunderstorms are also
possible during this timeframe, with HREF probability of thunder up
to 20 percent in the aforementioned region. Winds will increase this
afternoon, with sustained winds across much of the Snake River Plain
and Arco Desert reaching around 25 mph. There is a marginal chance
for Lake Wind Advisory conditions on American Falls Reservoir later
this afternoon/evening, during which time southwest winds could
briefly reach low-end criteria at 20 mph, especially across the
northern extent of the reservoir. The National Blend indicates a 25-
50% chance of reaching that criteria across the reservoir between 4
and 8 PM today.

The ridge of high pressure will quickly rebound tomorrow, allowing
temperatures to continue to warm. Many low elevations areas will
warm to around 90 degrees Tuesday and/or Wednesday. By mid-week, we
will begin to feel the influence of a Pacific closed low which will
move onshore and inland Wednesday, shifting the area of high
pressure further east. Winds will increase again Wednesday
afternoon, with gusts ranging 30 to 45 mph across Southeast Idaho.
Chances for showers and thunderstorms will become increasingly more
widespread as the next low pressure system shifts east and
temperatures will run relatively much cooler the latter half of the
week.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 521 AM MDT Mon May 11 2026

VFR conditions forecast areawide. Shortwave working through to our
north will bring high clouds and breezy winds today. 20 to 30 kt
gusts are forecast at all terminals. Have retained VCSH at KDIJ this
afternoon with confidence in a direct shower and/or thunderstorm too
low to include in the forecast (less than 20% chance).

&&

.PIH WATCHES/WARNINGS/ADVISORIES...
None.

&&

$$

DISCUSSION...Cropp
AVIATION...Cropp