955
FXUS65 KMSO 271802
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
1202 PM MDT THU AUG 27 2026
DISCUSSION
KEY MESSAGES:
- ISOLATED THUNDERSTORMS ACROSS WESTERN MONTANA THROUGH LATE-
AFTERNOON, WITH OUTFLOW WIND GUSTS TO 40 MPH AND LIGHTNING
BEING THE PRIMARY STORM THREATS.
- A COLD FRONT ARRIVES SATURDAY, BRINGING COOLING TEMPERATURES,
GUSTY WESTERLY WINDS, AND PRECIPITATION.
SATELLITE IMAGERY LATE THIS MORNING SHOWS AN UPPER LEVEL WAVE
MOVING ACROSS EASTERN WASHINGTON AND OREGON. SHOWERS AND
THUNDERSTORMS HAVE DEVELOPED THIS MORNING ACROSS MUCH OF WESTERN
MONTANA AND LEMHI COUNTY, ID FUELED BY MID-LEVEL MOISTURE AND
INSTABILITY AS THIS UPPER LEVEL WAVES CONTINUES TO MARCH EASTWARD.
HIGH-RESOLUTION MODELS AND FORECAST SOUNDINGS SUGGEST CONVECTION
WILL IMPACT WESTERN MONTANA THROUGH MID-LATE AFTERNOON BEFORE
SHIFTING EAST OF THE DIVIDE BY EARLY THIS EVENING. SOUTHWEST TO
WESTERLY WIND GUSTS OF 20-30 MPH WILL DEVELOP BY LATE-AFTERNOON
THROUGH THE EARLY EVENING AS THE TROUGH PUSHES THROUGH, ACTING TO
ENHANCE VERTICAL MIXING, WITH WINDS ALOFT MIXING TO THE SURFACE.
LOOKING AHEAD TO FRIDAY AND THE WEEKEND, A LOW REMAINS ON TRACK
TO MOVE ACROSS THE PACIFIC NORTHWEST INTO THE NORTHERN ROCKIES
BY LATE SATURDAY INTO SUNDAY. DAYTIME HIGH TEMPERATURES WILL DROP
15-20F BY SUNDAY. SHOWERS AND THUNDERSTORM COVERAGE INCREASES
SATURDAY AS THE LOW MOVES FURTHER INLAND. AS FAR AS PRECIPITATION
GOES, CHANCES FOR WETTING RAINS (MORE THAN 0.10 IN) REACHES
80-90% FOR WEST-CENTRAL AND SOUTHWEST MONTANA, AS WELL AS LEMHI
COUNTY. CONFIDENCE FOR WETTING RAIN DECREASES ACROSS NORTHWEST
MONTANA, AS PROBABILITIES FOR WETTING RAINS DROP BELOW 30 PERCENT.
TEMPERATURES REBOUND EARLY NEXT WEEK TOWARDS SEASONAL NORMALS,
WHILE ENSEMBLE SOLUTIONS ARE INDICATING MORE UNSETTLED WEATHER
LATER IN THE WEEK.
AVIATION
WEST-SOUTHWEST SURFACE WIND GUSTS THIS AFTERNOON AND
ISOLATED THUNDERSTORMS ARE THE PRIMARY WEATHER CONCERNS. SURFACE
WINDS WILL INCREASE BY 2100-2200Z, GUSTING TO 15-25 KNOTS, LOCALLY
UP TO 40 KNOTS WITH STRONGER THUNDERSTORM OUTFLOWS. ISOLATED
THUNDERSTORMS WILL CONTINUE TO DEVELOP AND MOVE QUICKLY WEST TO
EAST ACROSS WESTERN MONTANA, WITH PROBABILITIES FOR IMPACTS
GENERALLY LESS THAN 20%, WITH THE EXCEPTION OF KBTM. FOR KBTM,
PROBABILITIES FOR TSRA AND OUTFLOW WINDS UP TO 40KTS INCREASE TO
30% BETWEEN 27/2000-2300Z, AS ANOTHER ROUND OF CONVECTION
DEVELOPS ALONG THE DIVIDE AND MOVES TOWARDS THE AIRFIELD THIS
AFTERNOON.
MSO WATCHES/WARNINGS/ADVISORIES
MT...NONE.
ID...NONE.
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