531
FXUS65 KMSO 240803
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
203 AM MDT FRI JUL 24 2026
DISCUSSION
KEY MESSAGES:
- ELEVATED FIRE WEATHER CONDITIONS (HOT, DRY, BREEZY) STARTING
TODAY AND LASTING INTO THE WEEKEND REGION-WIDE.
- WILDFIRE SMOKE DEGRADING AIR QUALITY AND REDUCING VISIBILITY
FOR THE NEXT SEVERAL DAYS AND LIKELY WELL INTO NEXT WEEK.
THE REGION REMAINS ON THE WESTERN PERIPHERY OF A LARGE-SCALE
UPPER-LEVEL RIDGE. PERSISTENT SYNOPTIC SUBSIDENCE WILL MAINTAIN
HOT, DRY, AND SMOKY CONDITIONS THROUGH THE WEEKEND, WITH NO
WIDESPREAD PRECIPITATION EXPECTED.
BREEZY SOUTHWESTERLY WINDS TODAY THROUGH SUNDAY, COMBINED WITH
LOW RELATIVE HUMIDITY AND HOT TEMPERATURES, WILL RESULT IN
ELEVATED FIRE WEATHER CONCERNS. RED FLAG WARNINGS ARE NOT
CURRENTLY PLANNED; MARGINAL WIND SPEEDS AND RELATIVELY MOIST
FUELS/SOIL KEEP CONDITIONS JUST BELOW WARNING THRESHOLDS. HOWEVER,
ELEVATED FIRE WEATHER CONDITIONS AND INCREASED FIRE BEHAVIOR
REMAIN EXPECTED ON EXISTING BURNS OR NEW IGNITIONS.
DEEP SOUTHWESTERLY FLOW WILL CONTINUE TRANSPORTING WILDFIRE SMOKE
FROM WASHINGTON AND OREGON INTO IDAHO AND MONTANA, MAINTAINING
POOR AIR QUALITY AND REDUCED VISIBILITY ACROSS THE REGION. DESPITE
HOT DAYTIME TEMPERATURES, HEAT ADVISORIES ARE NOT ANTICIPATED AT
THIS TIME DUE TO SUFFICIENT OVERNIGHT TEMPERATURE RECOVERY AND
SMOKE COVER LIMITING PEAK AFTERNOON HEATING.
SOUTHWESTERLY FLOW ALOFT WILL PERSIST THROUGH MUCH OF NEXT WEEK,
MAINTAINING HOT AND MOSTLY DRY CONDITIONS ALONGSIDE TYPICAL
AFTERNOON GUSTY WESTERLY WINDS. MONSOONAL MOISTURE WILL REMAIN
PREDOMINANTLY SUPPRESSED TO THE SOUTH, LIMITING THUNDERSTORM
POTENTIAL TO OCCASIONAL, SLIGHT CHANCES ACROSS LEMHI COUNTY AND
SOUTHWEST MONTANA. GIVEN THE HOT AND DRY LOW LEVEL AIR, GUSTY
OUTFLOW WINDS WILL BE A CONCERN NEAR ANY THUNDERSTORMS.
AVIATION
WILDFIRE SMOKE (FU/HZ) REMAINS THE PRIMARY PREVAILING
HAZARD ACROSS THE REGION, CAUSING PERIODIC MVFR SURFACE VISIBILITIES.
VISIBILITY WILL DROP LOWEST OVERNIGHT THROUGH MID- MORNING UNDER
NOCTURNAL INVERSIONS, FOLLOWED BY PARTIAL AFTERNOON CLEARING DUE
TO DEEP BOUNDARY-LAYER MIXING. THE HIGHEST SMOKE CONCENTRATIONS
WILL PERSIST FROM NORTH-CENTRAL IDAHO INTO NORTHWEST MONTANA.
PATCHY VALLEY FOG IS ALSO POSSIBLE THIS MORNING IN AREAS THAT
RECEIVED RAINFALL LAST EVENING.
DEEP DIURNAL MIXING WILL YIELD WIDESPREAD SOUTHWESTERLY WIND
GUSTS OF 20 TO 25 KNOTS DURING PEAK HEATING EACH AFTERNOON (TODAY
AND SATURDAY). OTHERWISE, MOSTLY DRY CONDITIONS WILL PREVAIL, WITH
ONLY ISOLATED AFTERNOON THUNDERSTORMS POSSIBLE ACROSS LEMHI
COUNTY AND SOUTHWEST MONTANA. HIGH DENSITY ALTITUDE WILL IMPACT
AIRCRAFT PERFORMANCE DURING PEAK AFTERNOON HEATING, PARTICULARLY
AT HIGHER-ELEVATION TERMINALS SUCH AS KBTM.
MSO WATCHES/WARNINGS/ADVISORIES
MT...NONE.
ID...NONE.
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