658
FXUS65 KMSO 301835
AFDMSO

Area Forecast Discussion
National Weather Service Missoula MT
1235 PM MDT Thu Jul 30 2026

.DISCUSSION...

KEY MESSAGES:

-  Thunderstorms this afternoon and evening east of US-93 through
   10pm MDT bringing risk of lightning and strong outflow gusts.

-  Critical fire weather this weekend.

-  Cooldown for Sunday and Monday with temperatures rebounding to
   near/above normal by Tuesday and Wednesday of next week.

Hot, dry, and smoky conditions remain entrenched today with high-
based, inverted-V profile, dry thunderstorms developing this
afternoon primarily east of US-93 and along the HWY 200 corridor.
Rain totals will be minimal and isolated, primary hazards from
convection today between 4pm and 10 pm MDT will be lightning (and
any new fire starts that occur) and strong erratic outflow winds
gusting 30 to 45 mph (low chance for an isolated 50+ mph). Friday
will be mostly convection-free, hot, dry, and smoky serving as the
calm (and continuing to pre-condition wildland fuels) before this
weekend`s weather event.

High confidence remains in a critical fire weather pattern this
weekend as a dry Pacific trough pushes a cold front through the
region. Pre-frontal heating peaks on Saturday with temperatures
approaching 100 degrees in valleys south of I-90 and in southwest
Montana. Widespread westerly winds ramp up Saturday afternoon,
gusting 25 to 40 mph (with ridgetops approaching 50 mph) alongside
relative humidities dropping to at least 10-15%. Current Fire
Weather Watches remain active, with Red Flag decisions planned to
be finalized on Friday`s day shift. Post- frontal cold air
advection drops temperatures 10 to 20 degrees for Sunday and
Monday, though strong westerly breezes persist across the Northern
Rockies on Sunday keeping SW Montana in critical fire weather
conditions through Sunday evening.

Northwest flow dominates Monday and Tuesday, keeping highs below
seasonal averages with cool overnight lows. Isolated mountain
showers are possible but moisture will be severely limited. A
thermal ridge begins to rebuild by midweek next week marking the
return of above normal high temperatures.

&&

.AVIATION... Hot temperatures will keep density altitudes elevated
across all regional terminals through Saturday (peaking near
9,000 ft at KBTM). Deep southwesterly flow continues to transport
wildfire smoke across the region, degrading slant-range visibility
and keeping surface visibilities near 6SM. High-based isolated dry
thunderstorms develop 30/2000z through 31/04z along and mostly
east of a straight-line from KHRF to KMSO. 8-12k ft AGL cloud
bases will produce minimal surface rain nor prolonged visibility
reductions, but strong erratic outflow gusts of 25-35 knots
(isolated 45 knots) near KBTM, KSMN, and KHRF remain the main
hazard.

&&

.MSO WATCHES/WARNINGS/ADVISORIES...
MT...Fire Weather Watch from Saturday afternoon through Saturday
     evening for Bitterroot...East Lolo...Flathead Reservation...
     Flathead/Glacier Park...Kootenai...West Lolo.

     Fire Weather Watch from Saturday afternoon through Sunday
     evening for Deerlodge/West Beaverhead...East Beaverhead.

ID...Fire Weather Watch from Saturday morning through Saturday
     evening for Clearwater/Nez Perce...Palouse/Hells Canyon.

&&

$$