067
FXUS65 KBOI 280941
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
341 AM MDT Tue May 28 2024

.SHORT TERM...Today through Thursday night...Active weather is
anticipated today as an upper level trough over the eastern
Pacific moves inland today. Southwest flow aloft will strengthen
as this feature approaches southeast Oregon and southwest
Idaho, bringing even warmer temperatures and increasing
moisture. Highs will reach the upper 80s in the lower valleys,
with a 20-40% chance to hit 90 degrees. Instability will
develop this afternoon ahead of the trough, and shower and
scattered thunderstorm development will favor the higher
terrain. However, the approaching trough will provide lift for
storm formation and will aid storm organization and movement
into lower valleys including the Treasure and Magic valleys.
Storms may become strong to severe with wind gusts to 60 mph the
primary hazard, but hail and heavy rain will also be possible.
Showers and thunderstorms will decrease overnight as the trough
and a cold front push through, with most activity limited to the
central Idaho mountains after midnight MDT. The cold front will
move across the area this evening, reaching the Magic Valley
near or shortly after midnight MDT. Gusts to 45 mph are possible
along the front, but could be stronger if thunderstorm outflows
enhance the front. This may result in blowing dust reducing
visibility.

Much cooler and drier air will arrive behind the cold front on
Wednesday. Dry conditions will return with temperatures nearly
20 degrees cooler than today. Winds will be breezy as the trough
passes through, bringing gusts 20-30 mph, except up to 40 mph in
the Magic Valley. Thursday will be very similar to Wednesday as
dry northwest flow aloft sets up behind the trough, keeping
temperatures around 5 degrees below normal. Additionally, winds
will be lighter, but still breezy across the Magic Valley.

.LONG TERM...Friday through Tuesday...Models are in generally good
agreement with regard to the large-scale pattern through early next
week, but there are some differences with respect to short-wave
troughs embedded in a westerly flow aloft. A weak upper trough could
move through over the weekend, but precip chances remain slim (less
than 20 percent) and confined to the far north. A more impressive
trough could arrive early next week, but there are significant
differences in its strength. There is a low (15-30 percent chance)
of rain showers across the northern areas starting Sunday night and
continuing into Tuesday. Near normal temperatures are favored on
Friday, warming to slightly above normal temperatures for the
remainder of the period. There is at least a 60 percent chance that
high temperatures exceed 80F in portions of the Snake Plain from
Saturday until Tuesday, including Boise.

&&

.AVIATION...Mainly VFR. Variable mid-high level clouds increasing
through the day, mainly in the afternoon and evening. Dry through
18Z, then low-moderate confidence (30-60 percent chance) of showers
and thunderstorms after 18Z. Some of the thunderstorms will be
capable of producing MVFR conditions accompanied by +RA, small hail,
and strong gusty outflow winds up to 50 kt. Surface winds: E-SE 5-15
kt becoming mainly SW-W after 18Z, except variable gusty/erratic
winds near thunderstorms. 10k ft MSL winds: SW 15-30 kt.

KBOI...VFR with mostly clear skies in the morning and increasing mid-
high clouds in the afternoon. Winds SE around 12 kt becoming NW
around 10 kt after 18Z. Low chance (20%) of thunderstorms in the
vicinity between 28/22Z and 29/00Z. Higher chances (50%) after
29/00Z with gusty outflow winds to 30 kt.

&&

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

&&

$$

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SHORT TERM...ST
LONG TERM....BW
AVIATION.....BW