466
FXUS65 KBOI 312326
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
526 PM MDT Sun May 31 2026

.UPDATE...Updated aviation discussion.

&&

.KEY MESSAGES...
- Warmer and decreased wind Monday with temperatures rising to
  near normal.

- Temperatures warming to around 5-10 degrees above normal by
  mid week.

- Breezy Wednesday and Thursday with shower and thunderstorm
  potential across the north.

&&

.SHORT TERM /Through Tuesday Night/...
Issued 221 PM MDT SUN MAY 31 2026
An upper level low over Montana will slowly move northeast into
southern Canada by Monday night and Tuesday. The forecast area
will generally remain dry as the low pulls away but on Monday,
a weak trough from the Pacific Northwest will move across our
area and merge with the Montana low. This will introduce a
10-20% chance of showers and thunderstorms to the central Idaho
mountains, mainly over eastern Valley County, and the upper
reaches of the Boise River Basin. Temperatures will increase up
to 5 degrees on Monday with the upward trend in temperatures
continuing on Tuesday as a weak upper level ridge moves over
the forecast area. Winds will be lighter Monday and Tuesday.

&&

.LONG TERM /Wednesday through Sunday/...
Issued 221 PM MDT SUN MAY 31 2026
Daytime temperatures will continue to warm to about 10 degrees
above normal Wednesday as southwest flow develops ahead of a
weak, Pacific trough. The trough and accompanying cold front are
forecast to arrive late Wednesday, introducing shower and
thunderstorm chances across northern Harney and Malheur
Counties, and Baker County, and west-central Idaho Wednesday
into Thursday. Winds will become breezy behind the cold front on
Thursday, with temperatures lowering by several degrees. Dry
and warming conditions will develop once again Friday ahead of
the next Pacific trough expected for the weekend. This system
will support stronger wind gusts for both Saturday and Sunday as
it tracks east through Oregon and Idaho. Models currently
disagree on shower/thunderstorm development, but the arrival of
the cold front late Saturday will ensure much cooler
temperatures by Sunday.

&&

.AVIATION /00Z Monday through Tuesday/...
Issued 522 PM MDT SUN MAY 31 2026
VFR. Mid to high clouds, and some cumulus buildups over central
Idaho during the afternoon Monday. Surface winds WNW 10-20 kt,
becoming less than 10 kt overnight, before shifting to the WNW
after 18Z Monday and increasing to 8-12 kt. Winds aloft at 10kft
west 15-25 kt.

KBOI...VFR with some high clouds. Surface winds WNW 10-20 kt and
gusty through 02Z, then generally WNW less than 8 kt through 18Z
before increasing to 8-12 kt.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...None.

OR...None.

&&

$$

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AVIATION.....MC
SHORT TERM...TL
LONG TERM....TL