387
FXUS65 KBOI 121548
AFDBOI

Area Forecast Discussion
National Weather Service Boise ID
948 AM MDT Sat Jul 12 2025

.DISCUSSION...Current satellite imagery shows smoke aloft over
southeastern Oregon, originating from fires in northern
California. This smoke is expected to linger throughout the day.
Otherwise, clear skies are expected with temperatures warming
to the mid-90s across lower elevations as high pressure aloft
builds in over our area. Monday and Tuesday are looking to be
the hottest days of the week with temperatures around 100
degrees throughout the Snake Plain. Current forecast looks to be
on track, no updates needed.

&&

.AVIATION...VFR. Clear sky. Localized smoke near wildfires in
central ID and near OR/NV border. Surface winds: variable less than
10 kt, becoming W-NW 5-15 kt this afternoon, with gusts 15-25 kt
from KBOI eastward through the Magic Valley. Winds aloft at 10kft
MSL: NW 5-15 kt.

KBOI...VFR. Surface winds: light and variable this morning, then
W-NW 8-12 kt with 15-20 kt gusts this afternoon.

Sunday Outlook...VFR. Localized smoke near wildfires. High
density altitude due to hot temperatures. Surface winds: NW 5-15
kt, with 15-25 kt afternoon gusts.


&&

.PREV DISCUSSION...
SHORT TERM...Today through Monday night...The building heat
will be the main impact through Monday as the heat dome over the
Desert SW expands northward. Highs today will run about 5
degrees warmer than normal (mid-upper 80s mtn valleys to mid-
upper 90s lower elevations). Another 3-5 degrees of warming
into Sunday will place lowest elevations above 100. Have gone
with a Heat Advisory for Sun/Mon for the Lower Treasure Valley
given high temps generally in the 101-104 range each day and
relatively warm ~70 degree overnight lows Sunday night. Most, if
not all areas remain dry through the period, but will be keeping
an eye on mid-level moisture under the building high. It doesn`t
look overly impressive but a handful of the high resolution
models are showing potential for afternoon shower and
thunderstorm development across s-central Oregon and the higher
terrain in the central ID mtns on Sunday. For now have kept
ghost pops (sub 10% chance) over southern Harney County and
eastern Valley County and the eastern Boise Mtns. For Monday,
the low chance of showers and thunderstorms spreads out along
the northern NV border while potential in the central Idaho mtns
shifts eastward ahead of an advancing trough. Lightning, gusty
winds and little rain would be main concern from storms that
develop.

LONG TERM...Tuesday through Saturday...An upper level trough
will move south from Canada into the Northern Rockies on
Tuesday. However, there is still significant model disagreement.
Most of the GEFS members keep the trough further north
resulting in continued hot temperatures in our area, while the
EC and Canadian ensembles continue to bring it further south,
sending a mostly dry cold front across our area with
temperatures cooling to closer to normal and breezy winds
developing. Breezy winds with low humidity may result in
elevated fire weather conditions. Uncertainty carries through to
Wednesday as the trough moves east. The trough will bring
around a 10% chance of showers and thunderstorms to the central
Idaho mountains Tuesday with lower chances elsewhere. The upper
level pattern remains somewhat uncertain after Wednesday, but
favors temperatures around 5 degrees above normal as a zonal to
southwest flow aloft sets up over the area. Some models continue
to hint at limited moisture moving into our area resulting in
shower and thunderstorm potential, but most keep the moisture to
our east. For now, will keep shower and thunderstorm mention
out of the forecast through the extended.

&&

.BOI WATCHES/WARNINGS/ADVISORIES...
ID...Heat Advisory from noon Sunday to 9 PM MDT Monday IDZ012.
OR...Heat Advisory from noon MDT /11 AM PDT/ Sunday to 9 PM MDT /8
     PM PDT/ Monday ORZ064.

&&

$$

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DISCUSSION...NF
AVIATION.....LC
SHORT TERM...DG
LONG TERM....ST