154
FXUS65 KPIH 152337
AFDPIH

Area Forecast Discussion
National Weather Service Pocatello ID
537 PM MDT Sun Jun 15 2025

.KEY MESSAGES...

- Weak low pressure will bring a threat of precipitation and
  thunderstorms to areas from Sun Valley north to the Montana
  border on Monday.

- Breezy over Craters of the Moon and the Arco Desert.

- Windy on Friday, then turning much cooler for the upcoming
  weekend.

&&

.SHORT TERM /THROUGH MONDAY NIGHT/...
Issued at 1234 PM MDT Sun Jun 15 2025

While tonight is expected to be quiet with the thunderstorm and
shower activity staying north in Montana, an approaching upper
level trough will bring a slight chance to chance level threat
to the northern half of the forecast area, as early as Mon
morning. Any showers or thunderstorms should disappear during
the early evening.

This low will have little effect on temperature, bringing
things slightly colder, on the order of 1 to 3 deg F. Wind will
increase, but only the Craters of the Moon NM and the Arco
Desert will see wind exceed even 15 mph, save for mountain
ridges.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 1234 PM MDT Sun Jun 15 2025

Weak shortwave finishes traversing through East Idaho on
Tuesday, with mainly isolated thunderstorms during the afternoon
for the Island Park/Yellowstone region. Tuesday also still
looks to be the "coolest" day of the week with highs generally
around 80 for most lower elevation locations. Temperatures
rebound for Wednesday and Thursday, potentially reaching mid-90s
for some areas Thursday, mainly the Eastern Magic Valley and
Snake River Plain. Gusty winds continue for each afternoon. The
next system approaches the PacNW coast Friday as a deep closed
low just off the coast. Winds increase across the region, and
NBM means are already pushing Wind Advisory for portions of the
Upper Snake Plain Friday afternoon. As the low is projected to
swing across the region for the weekend, temps cool off and we
see increased chances for precipitation. There is still quite a
spread across precipitation chances and temperatures. The
ensemble clusters all agree on a trough for the weekend, varying
in depth and slightly in timing.

&&

.AVIATION /00Z TAFS THROUGH 00Z TUESDAY/...
Issued at 537 PM MDT Sun Jun 15 2025

Upper-level clouds will continue to build into eastern Idaho
out of the southwest overnight and throughout the day Monday as
conditions remain dry. Light winds will return overnight ahead
of a diurnal increase during the daytime hours Monday, with
gusts peaking around 15-25 kts. Best shower and thunderstorm
development for Monday afternoon/evening looks to remain
confined to the Central Mountains and Continental Divide,
however the HREF model probability of thunder does show a 10-20%
chance at KPIH, KIDA, and KSUN and 30-40% chance at KDIJ, but
only less than a 10% chance at KBYI. Given variability in model
guidance on timing and placement of shower and thunderstorm
development with the bulk of model guidance keeping activity
away from terminals, have kept with a dry forecast for now as we
evaluate the latest model guidance for future TAF issuances.

&&

.FIRE WEATHER...
Issued at 200 AM MDT Sun Jun 15 2025

Isolated thunderstorms are possible across the Lemhi region
this afternoon. Areal coverage for isolated thunderstorms
extends further south into the central mountains and perhaps the
southern highlands Monday afternoon. Peak gusts this afternoon
and Monday afternoon will likely be 20 to 25 mph and minimum
humidities in the teens to low 20s.

&&

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

&&

$$

SHORT TERM...Messick
LONG TERM...DMH
AVIATION...MacKay
FIRE WEATHER...13