429
FXUS65 KMSO 270851
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
251 AM MDT MON OCT 27 2025
DISCUSSION
KEY MESSAGES:
- UNSETTLED WEATHER CONTINUES TODAY AS A RIDGE STARTS BUILDING
OVER THE REGION.
- MODELS WAIVER ON THE IMPACTS OF A SHORT WAVE MOVING THROUGH THE
RIDGE ON WEDNESDAY.
- THE NEXT SYSTEM ARRIVES THIS WEEKEND WITH MORE RAIN AND HIGHER
SNOW LEVELS.
THIS MORNING STARTS OUT WITH THE NORTHERN ROCKIES UNDER THE BASE
OF A TROUGH OVER THE REGION. THAT IS RESULTING IN SNOW SHOWERS
THIS MORNING, AND SOME MAY EVEN REACH THE VALLEY FLOORS OF WESTERN
MONTANA. BUT THESE SHOWERS WILL PEAK IN INTENSITY AND COVERAGE
THIS MORNING AS A RIDGE STARTS TO BUILD INTO THE REGION TODAY.
THAT RIDGE WILL BE FIRMLY IN PLACE BY TUESDAY MORNING.
MODELS HAVE TRENDED WETTER AGAIN WITH A SHORTWAVE MOVING THROUGH
THE RIDGE ON WEDNESDAY. AS A RESULT, IT LOOKS MORE LIKELY THAT
NORTHWEST AND WEST CENTRAL MONTANA WILL PICK UP SOME SHOWERS,
ESPECIALLY IN THE MOUNTAINS ON WEDNESDAY. THIS WILL BE A QUICK
MOVING SHORTWAVE, SO LITTLE TO NO IMPACTS ARE EXPECTED FROM THE
SHOWERS AT THIS TIME.
THE NEXT WEATHER SYSTEM ARRIVES LATE FRIDAY OR EARLY SATURDAY.
ONCE AGAIN, IT WILL BE AN ATMOSPHERIC RIVER BRINGING QUITE A LOT
OF MOISTURE IN FROM THE PACIFIC. AT THIS TIME, THE MOISTURE
AMOUNTS DO LOOK LOWER THAN THE LAST 2 ATMOSPHERIC RIVER EVENTS
WE'VE HAD RECENTLY, AND THE SNOW LEVELS ALSO LOOK TO REMAIN NEAR
OR ABOVE 5,000 FT FOR THE DURATION OF THE EVENT.
AVIATION
WE START THE DAY OUT TODAY UNDER THE BASE OF A COLD
TROUGH WITH SOME SHOWERS AND LOW SNOW LEVELS. ACCUMULATING SNOW AT
AREA TERMINALS IS UNLIKELY DUE TO WARM GROUND TEMPERATURES, EXCEPT
AT KBTM WHICH IS AT AN ELEVATION NEAR 5,000 FT. EXPECT SHOWER
ACTIVITY TO PEAK EARLY IN THE DAY AS A RIDGE STARTS BUILDING OVER
THE REGION. ANY IMPACTS TO CEILING AND VISIBILITY AT AREA
TERMINALS IS EXPECTED TO BE MVFR AND LAST LESS THAN AN HOUR IF IT
OCCURS AT ALL.
MSO WATCHES/WARNINGS/ADVISORIES
MT...WINTER WEATHER ADVISORY UNTIL NOON MDT TODAY FOR
BITTERROOT/SAPPHIRE MOUNTAINS...BUTTE/BLACKFOOT REGION...
KOOTENAI/CABINET REGION...LOWER CLARK FORK REGION...
POTOMAC/SEELEY LAKE REGION...WEST GLACIER REGION.
ID...WINTER WEATHER ADVISORY UNTIL NOON MDT /11 AM PDT/ TODAY FOR
LOWER HELLS CANYON/SALMON RIVER REGION...NORTHERN
CLEARWATER MOUNTAINS...SOUTHERN CLEARWATER MOUNTAINS...
WESTERN LEMHI COUNTY.
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