Area Forecast Discussion
Issued by NWS Boise, ID

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877
FXUS65 KBOI 041549
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
949 AM MDT Sat Oct 4 2025

.DISCUSSION...Breezy winds are already kicking up across most of
the Snake River Plain, with Twin Falls seeing gusts up to 35
mph. Scattered low stratus clouds remain around the area, with a
few rain showers primarily in South Central Idaho. Precipitation
will linger in high terrain today, with light snow above 7500
feet today. Snow levels will fall to 6500-7000 feet tomorrow.
Winds will remain elevated throughout the day, gradually
weakening by the late afternoon. Much cooler temperatures with
mostly dry conditions and lighter winds are still anticipated
tomorrow. No updates necessary to the forecast.

&&

.AVIATION...Mostly VFR. Low cloud ceilings with IFR/MVFR
conditions will continue across the Western Magic Valley until
afternoon. Isolated rain showers will occur across the area,
primarily in high terrain and Magic Valley. Mtns obscured in
low ceilings and precip. Snow levels 7000 ft MSL dropping to
6500 ft MSL tonight. Surface winds: W-NW 10-20 kt gusting up to
30 kt Saturday afternoon, with localized gusts up to 40 kt in
the Snake Plain. Winds calm to N-NW 5-15 kt after Sun/06z.
Winds aloft at 10 kft MSL: N-NW 15-25 kt.

KBOI...VFR. Mostly cloudy with a few low clouds this morning
near foothills. Surface winds: NW 10-20 kt with gusts near 35
kt, decreasing to W-NW 5-15 kt after Sun/03Z.

Sunday Outlook...Patchy AM fog for sheltered mountain valleys and
basins. Isolated to scattered showers continuing over central Idaho
mountains. MVFR/IFR in heavier rain showers, IFR/LIFR in snow. Snow
levels 6500-7000 ft MSL. Mountains obscured in precip. Surface
winds: NW-NE 5-15 kt. KTWF/KJER: SW-NW 5-15 kt.

&&

.PREV DISCUSSION...
SHORT TERM...Today through Monday night...
Areas of precipitation associated with a shortwave trough
were observed this morning over south-central and southeast
Idaho, with the western Magic Valley along the edge of a
broader precipitation swath. Scattered showers are expected to
persist and develop later this morning across the western Magic
Valley into the Camas Prairie, diminishing by sunset. Breezy
winds are also expected through the Snake Plain this afternoon,
with gusts over 40 mph forecast to occur along the I-84 corridor
between Mountain Home and Twin Falls. Precipitation chances
of roughly 20-30% linger into Sunday across the central Idaho
Mountains and western Magic Valley, as a weak disturbance moves
southward out of western Canada. Snow levels fall to around 7000
feet on Sunday, which will lead to light snow accumulation in
the highest mountain peaks.

Additionally, the cooler fall air mass will remain in place
throughout the weekend. Drier low-level air will overspread most
of the region Sunday, and will promote colder overnight
temperatures, especially on Monday morning. Areas of frost are
likely in higher elevation valleys of eastern Oregon and
southwest Idaho as sub-freezing temperatures become more
widespread on Sunday and especially Monday morning.

LONG TERM...Tuesday through Saturday...Brief shortwave ridging
Tuesday will quickly transition into southwesterly flow aloft
Wednesday. The feature of cause for this is a potent, positively
tilted upper-level trough extending off of Canada into the Pacific
Ocean, which will meander around the Pacific Northwest coast through
Friday. This will enable moisture transport into the region, as well
as aligning favorably against topography to introduce precipitation
chances beginning Thursday morning onwards. Chances will be highest
for higher elevations Thursday, however notable chances will begin
for lower elevations from Friday on. All of the long range models
have the upper-level trough/low move in retrograde, however they do
so in varying degrees. This, combined with the ECMWF having a
tropical systems remnant moisture be pulled all the way north into
the Great Basin, paint a picture of a wet end of week/weekend. The
extent of how much precipitation may fall is too uncertain at this
time. A gradual warming trend will be seen through the period, with
temperatures climbing from near normal to 5-10 degrees above normal.

&&

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

&&

$$

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DISCUSSION...SA
AVIATION.....SA
SHORT TERM...JR
LONG TERM....CH