Area Forecast Discussion
Issued by NWS Boise, ID

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000
FXUS65 KBOI 232012
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
212 PM MDT Sat Mar 23 2024

.SHORT TERM...Tonight through Monday night...Rain showers and
gusty winds associated with a cold front are moving east out of
our area, leaving a colder airmass and mostly cloudy skies in
its wake. Snow levels behind the front are 4000-5000 ft MSL.
Instability caused by the colder airmass is already supporting
the development of scattered convective showers in SE Oregon. As
these showers continue to pop up and move eastward, a few may
strengthen and become thunderstorms. Thunderstorm coverage will
be mostly in SE Oregon and W-Central Idaho. Confidence for
lightning in the Lower Snake Plain is low, but a stray bolt or
two is not impossible especially over the foothills. Breezy
winds will continue through Saturday evening before weakening
overnight. Breeziness returns each afternoon, strongest in the
Magic Valley up to Mountain home, gusting to 30 kts Sunday
afternoon/evening.

Scattered light precipitation continues through the rest of the
short term period as the upper low that brought the cold front
through moves overhead, followed by moist northwesterly flow and
a shortwave on Monday. Some mild instability in central Idaho
Sunday afternoon may support a stray thunderstorm or two. Snow
levels drop to 3500-4500 ft MSL on Monday. Mountain snow showers
continue with only light accumulation. Morning lows on Monday
support snow reaching the surface in the Lower Snake Plain,
although chances for precip at this time are <10%, so confidence
is very low. Temps hold steady at about normal through the
short term.

LONG TERM...Tuesday through Saturday...Continued active weather is
anticipated throughout the extended period. Tuesday will maintain a
cold northwesterly flow, fostering showers primarily over elevated
terrain due to sufficient instability. Snow levels are forecasted to
linger between 3500-4500 ft MSL, accompanied by temperatures
slightly below average. Expect breezy northwest winds, particularly
in the afternoon. By Tuesday night into early Wednesday, a trough
will shift eastward as an upper-level ridge moves over the area,
ushering in drier conditions.

Wednesday will witness the approach of the next upper-level low to
the Pacific Northwest coast. This will induce strong southwesterly
flow aloft, leading to gusty winds, particularly in southeast
Oregon. Temperatures will rise, and snow levels are expected to
elevate to around 6000 ft MSL ahead of an approaching cold front.
Precipitation chances will heighten throughout the day, peaking
Wednesday night with the passage of the cold front. Moderate snow
accumulations are likely in mountainous regions, while lower valleys
can anticipate light to moderate rainfall.

On Thursday and Friday, southwesterly flow aloft will persist as the
low center remains southwest of the region. Periods of showers are
possible, influenced by weak embedded shortwaves within the flow.
However, the timing of these waves remains uncertain. The majority
of ensemble solutions indicate that the low center will stay well
south of the region through Saturday, with approximately 83% of
ensemble members favoring this scenario. Nonetheless, about 17% of
the ensembles, particularly the GFS ensembles, suggest a track
inland across Northern Nevada. Both scenarios could prolong the
precipitation threat into the weekend. Notably, a low track across
northern Nevada could bring heavy banded precipitation and lower
snow levels to around 4000 ft MSL across the forecast area.

&&

.AVIATION...Widespread snow showers along a cold front this
afternoon moving across the central mountains of Idaho. T VFR/MVFR
in rain showers, and MVFR/IFR in snow showers. Mountains obscured.
Snow levels 6-7 kft MSL lowering to 5-6kft along and behind the
front. Numerous showers and isolated thunderstorms will continue
through late this evening. Surface winds: SW-Nw 5-15 kt with gusts
to 25 kt. Winds aloft at 10kft MSL: W-SW 20-35 kt.

Sunday Outlook...Scattered to numerous showers will continue into
Sunday with snow levels 4-5 kft MSL. The highest coverage will be in
the afternoon across the mountains. Surface winds W-NW 10-25 kt,
strongest across s-central ID where gusts 30-40 kt are expected.

&&

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

&&

$$

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SHORT TERM...JM
LONG TERM....JDS
AVIATION.....JDS


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