Emmett Weather

563
FXUS65 KBOI 161700
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
1000 AM MST Tue Dec 16 2025

.DISCUSSION...Main forecast is still on track expecting a very
strong Pacific cold front early Wednesday morning with high
winds and moderate to heavy pcpn Wednesday, then rapid clearing,
calming, and cooling Wednesday night. Latest models warrant
upgrading our Wind Advisory to High Wind Warning in Idaho east
of Boise and south to the NV border. Heavy pcpn with the cold
front may cause rock slides in steep terrain in Idaho north of
the Snake Basin. Avoid the Banks-Lowman road and other roads
below steep terrain, if possible. The next Pacific warm front
will bring moderate to heavy pcpn again Thursday and Thursday
night due to another atmospheric river. Heavy snow may fall in
northern mountains Thursday night before changing to rain Friday
up to 6000 feet MSL north to 8000 feet south.

&&

.AVIATION...Patchy fog/mist around KONO to KMAN this morning.
Some mtn obscuration from low clouds. Otherwise, VFR through
afternoon. Rain arriving from SW after sunset. Snow for
elevations above 7-8 kft MSL. Low VFR/MVFR in heavier rain,
IFR/LIFR in snow. LLWS threat becoming area-wide late tonight.
Surface winds: SW-SE 5-15 kt, afternoon gusts to 20-30 kt for
SE Oregon and near ID/NV border. Gradually increasing
tonight/early Wed to SW-S 15-30 kt with to 30- 50 kt gusts,
locally higher on mtn tops. Winds aloft at 10kft: W-SW 25-40
kt, increasing to 45-70 kt overnight.

KBOI...Mainly VFR. A 60% chance of rain beginning around Wed/
02Z-03Z, increasing to 90% chance overnight. Brief MVFR
possible at precip onset prior to increasing wind speeds. Low
level wind shear threat ramping up overnight. Surface winds:
SE 5-15 kt, increasing to SE 15-20 kt overnight, with 25-30 kt
gusts. Then W-NW 15-25 kt with 35-45 kt gusts beginning approx
Wed/15Z with cold front.

&&

.PREV DISCUSSION...
SHORT TERM...Today through Thursday night...Zonal flow expected
over the short term with Pacific moisture moving inland late
this afternoon and evening. Models struggled with the moisture
overnight, predicting precipitation much of the area earlier
this morning, but nothing happened overnight. Expect dry
conditions through this afternoon before moisture streams inland
from the Pacific. Precipitation will become widespread as a
warm front moves in late this evening. Snow levels rise from
6500-7500` MSL this evening to 8000-9000` early Wednesday
morning. Then, a potent cold front moves through with heavy
showers along the front. Wind gusts of 50 to 60 mph possible
along the cold front on Wednesday morning as it moves through.
The timing is not as favorable as central and eastern ID to
realize the fullest potential of the winds. The strongest winds
will occur during the afternoon, as the front tracks east, where
a high wind warning is in effect for the Camas Prairie.
Precipitation quickly ends behind the front and the winds slowly
subside by Wednesday evening. After a brief lull, the next warm
front moves inland on Thursday morning. This will bring snow to
much of the area in the morning, before changing to rain below
8000` MSL by Thursday afternoon. Snow levels will remain lower
around the Wallowas, Hells Canyon, and around McCall until the
late evening before rising to around 6000-7000` MSL as cooler
air will hold on longer than the rest of the area. Snow amounts
of 6 to 12 inches possible on Thursday above 6500` MSL before
snow levels rise. The Snake Basin including the Treasure Valley
may see snow, but no accumulations expected.

LONG TERM...Friday through Tuesday...Moisture will persist
over the forecast area on Friday ahead of and along a cold
front expected by Friday evening. The strong mid-level jet in
place will support upslope precipitation across west-central
and central Idaho terrain, and will aid in valley shadowing
effects. Snow levels will still be on the higher side ahead of
the front, around 5000 feet MSL for the north and 7500 feet
for the south. A sharp gradient in snow levels will develop
with the arrival of the cold front, with 2500 feet for the
north and 6500 feet for the south by early Saturday. The lower
snow levels will result in moderate to heavy snow accumulations
for those higher elevations of central ID Friday into Saturday,
with liquid equivalent potentially exceeding an additional 1".
This period of precip over saturated, steep terrain will also
introduce rockslide concerns below the snow line. In addition
to precip, strong surface winds are anticipated across much of
the area Friday ahead of/along the cold front. Gusts will be
strongest across southeast Oregon and the mountains of southwest
Idaho. Meanwhile, temperatures are forecast to stay above
normal Friday, with the coldest air expected across west-
central/central Idaho and northeast Oregon. Temperatures should
lower by several degrees Saturday for all areas behind the cold
front, but above normal temperatures will still persist for
most.

As the aforementioned system exits, another windy and very wet
elongated trough will impact the area beginning early Sunday.
The accompanying plume of subtropical moisture will help to
amplify a ridge over the west as it brings in warmer air. Cool,
but above normal, temperatures on Sunday will jump up to 10-20
degrees above normal on Monday. Snow levels will be 3500 feet
to the north and 7000 feet to the south, then quickly rise to
6000-8000 feet by early Monday. Though precip chances are
forecast area-wide, the west-central/central Idaho terrain will
be favored once again. Periods of precip will continue Tuesday,
with the coldest air remaining to the northwest of the area.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Wind Advisory from 5 AM to 5 PM MST Wednesday
     IDZ011-013>016-029-030.
     High Wind Warning from 8 AM to 5 PM MST Wednesday IDZ028.
OR...Wind Advisory from 5 AM MST /4 AM PST/ to 11 AM MST /10 AM
     PST/ Wednesday ORZ061>063.

&&

$$

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DISCUSSION...LC
AVIATION.....ST
SHORT TERM...KA
LONG TERM....SH