904
FXUS65 KBOI 130945
AFDBOI
Area Forecast Discussion
National Weather Service Boise ID
345 AM MDT Fri Mar 13 2026
.KEY MESSAGES...
- Light rain and high-elevation snow in northern mountains
through Saturday night.
- High-winds and strong cold front shaping up for Saturday.
- Much colder but less windy Sunday.
- Rapidly warming Monday leading to record high temperatures
area-wide Tuesday through Friday.
&&
.SHORT TERM /Through Sunday Night/...
Breezy and mild again today and tonight, with light rain and high-
elevation snow continuing in northern-most mountains. Pcpn will
increase tonight in Idaho north of the Snake Basin, but other
areas in our CWA should stay dry, although cloudy.
Saturday looks increasingly likely to bring an impactful high-wind
event as models continue to bring an intense impulse inland within
already strong WNW-ly flow aloft over the north Pacific. Latest
models target southern Idaho for strongest winds while decreasing
the winds slightly in eastern Oregon. Our High Wind Watch will
continue as previously issued until we can better determine
exactly where to upgrade to High Wind Warning. The Snake Basin
east of Boise and south to the Nevada are presently of greatest
concern. Strongest winds should occur during and after passage
of a cold front around mid-day Saturday, and through the
afternoon. The overall pattern looks increasingly similar to
the pattern that brought the windstorm of December 17, 2025.
In addition, models continue to increase the thermal contrast
across the cold front, i.e., frontogenesis, with snow level
lowering all the way to valley floors late Saturday night as
pcpn ends. Total pcpn through Saturday night should be .30 to
.80 inch water equivalent in the West Central Idaho Mountains
and Boise Mountains, .10 to .30 inch in Baker County and the
Camas Prairie, and less than .10 inch elsewhere, but all areas
should get wet, even if only briefly, as the cold front passes.
Total snowfall should be 6 to 12 inches above 5500 feet MSL in
the Idaho mountains north of the Snake Basin. McCall will have
rain during most of the event, changing to snow only near the
end, with less than one inch snow accumulation.
Sunday will be clearing and 15 to 20 degrees colder than
Saturday, but the cold weather will be brief as a Pacific upper
ridge will soon build inland, with a warm front and light pcpn
again in northern areas Sunday night, followed by clearing and
rapid warming Monday on the way to record high temperature
Tuesday and beyond.
&&
.LONG TERM /Monday through Friday/...
As an upper level low moves well east of the region, high pressure
building over California rules the rest of the long term. Monday,
a 20-30% chance of precipitation across the north turns to rain
as snow levels rise to 7-8 kft MSL by that evening. Gusts in
the Magic Valley and Upper Snake Plain will be 25-35 mph in the
afternoon. The strong, moist flow driving the precip and gusts
moves north by Tuesday, kicking off our period of near record
temperatures. Monday will be 15 degrees warmer than Sunday, and
about 5-10 degrees above normal for this time of year. Tuesday,
temps rise to about 20 degrees above normal, threatening daily
high temperature records for a toasty St. Paddy`s day. Wednesday
through Friday temps hold steady at 20-25 degrees above normal.
Each day`s daily records will be threatened, monthly max temps
threatened, and we may set the record for our earliest 80 degree
day in Boise on Wednesday. During this warm period, winds
remain mild, afternoon RH values are 20-30% in lowlands and
30-50% in mountains, and skies are partly cloudy. The moist flow
to the north of the area stays close enough to bring a 10-20%
chance of rain showers across northeast Oregon and north-central
Idaho. While cloudy conditions may limit daytime heating in
these areas, temps will still be unseasonably warm.
&&
.AVIATION /06Z Friday through Saturday/...
Issued 1052 PM MDT THU MAR 12 2026
Generally VFR under mid to high clouds. Periods of
precipitation over the central ID mountains through Friday,
resulting in periods of MVFR/IFR conditions and mtn obscuration.
Areas of LLWS overnight, but generally under 30 kt. Snow
Levels: 6-7.5kft MSL. Surface winds: Variable up to 12 kt
overnight, becoming W-NW 10-20 kt with gusts to 20-30 kt Late
Sat/AM. Winds aloft at 10kft MSL: W 40-55 kt.
KBOI...VFR under mid to high clouds. LLWS overnight, although
generally under 30 kt. Surface winds: light and variable,
leaning NE overnight. Then W-NW 10-15 kt Fri/PM.
Weekend Outlook...On Saturday, a cold front will bring heavier
rain and snow to the central Idaho mountains, especially in the
morning, with light precipitation elsewhere. Windy on Saturday
along and behind the front. Precipitation decreasing Saturday
night, drier on Sunday. Areas of MVFR/IFR and mountain
obscuration in precipitation, otherwise VFR. Snow level lowering
to 4-6kft MSL Saturday behind the front. Surface winds: W-NW
20-30 kt with gusts to 45 kt Saturday, W-NW 5-15 kt Sunday.
&&
.BOI WATCHES/WARNINGS/ADVISORIES...
ID...High Wind Watch from Saturday afternoon through Saturday
evening for IDZ014>016-028>030.
OR...High Wind Watch from Saturday afternoon through Saturday
evening for ORZ061>063.
&&
$$
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SHORT TERM...LC
LONG TERM....JM
AVIATION.....NF
