348
FXUS65 KMSO 201943
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
143 PM MDT FRI MAR 20 2026
DISCUSSION
KEY MESSAGES:
- UNSEASONABLY WARM, DRY, AND WINDY CONDITIONS TODAY WILL CREATE
ELEVATED FIRE WEATHER CONCERNS, PRIMARILY ACROSS SOUTHWEST
MONTANA.
- LIGHT RAIN WILL PERSIST TODAY ACROSS NORTHWEST MONTANA BEFORE
A COLD FRONT ON SATURDAY BRINGS A RETURN TO SEASONAL
TEMPERATURES, GUSTY WINDS, AND SCATTERED SHOWERS.
- A BRIEF COOL DOWN THIS WEEKEND WILL BE FOLLOWED BY WELL-
ABOVE- AVERAGE TEMPERATURES MONDAY THROUGH WEDNESDAY, BEFORE A
POTENTIALLY WET, MOISTURE-RICH COLD FRONT ARRIVES LATE NEXT
WEEK.
THE REGION REMAINS SPLIT TODAY. A LINGERING PLUME OF MOISTURE
WILL KEEP LIGHT RAIN FALLING ACROSS NORTHWEST MONTANA, WITH SNOW
LEVELS HOLDING HIGH ABOVE 7,000 FEET. MEANWHILE, AREAS SOUTH OF
INTERSTATE 90 WILL EXPERIENCE NEAR-RECORD WARMTH, WITH AFTERNOON
HIGHS SOARING INTO THE UPPER 60S AND 70S. A TIGHTENING PRESSURE
GRADIENT WILL PRODUCE GUSTY SOUTHWEST WINDS OF 25 TO 35 MPH THIS
AFTERNOON. COMBINED WITH THE UNUSUAL WARMTH AND LOW HUMIDITY, THIS
WILL ELEVATE FIRE WEATHER CONCERNS ACROSS SOUTHWEST MONTANA AND
LEMHI COUNTY.
A PACIFIC COLD FRONT WILL SWEEP ACROSS THE NORTHERN ROCKIES ON
SATURDAY. THIS BOUNDARY WILL TRIGGER A PERIOD OF LIGHT TO MODERATE
CONVECTIVE SHOWERS. EXPECT A DROP IN TEMPERATURES BACK TO
SEASONAL NORMALS AND A BURST OF GUSTY WINDS AS THE FRONT PASSES
THROUGH. SNOW LEVELS WILL DROP BEHIND THE WEEKEND FRONT, BRINGING
MOUNTAIN SNOW BACK INTO THE FORECAST, WHICH IS UNLIKELY TO AMOUNT
TO MUCH FOR ACCUMULATIONS.
BEHIND SATURDAY'S FRONT, COOLER AND MORE UNSETTLED WEATHER WILL
LINGER THROUGH SUNDAY. HOWEVER, FORECAST MODELS ARE IN FAIR
AGREEMENT THAT THE WEATHER PATTERN WILL SHIFT QUICKLY, BRINGING A
RETURN TO WELL ABOVE AVERAGE TEMPERATURES FOR MONDAY, TUESDAY,
AND LIKELY WEDNESDAY.
BY WEDNESDAY OR EARLY THURSDAY, THE PATTERN SHIFTS AGAIN AS
ANOTHER COLD FRONT APPROACHES THE NORTHERN ROCKIES. THIS SYSTEM
WILL BE ASSOCIATED WITH ANOTHER ATMOSPHERIC RIVER, BRINGING THE
POTENTIAL FOR WIDESPREAD PRECIPITATION WITH HIGHEST AMOUNTS AGAIN
FOCUSED TO NORTH-CENTRAL IDAHO AND NORTHWEST MONTANA.
AVIATION
AN ACTIVE SOUTHWESTERLY FLOW REGIME WILL MAINTAIN VFR
CONDITIONS FOR MOST TERMINALS TODAY, THOUGH LOCALIZED MVFR
CEILINGS AND VISIBILITY REMAIN POSSIBLE ACROSS NORTHWEST MONTANA
DUE TO PERSISTENT LIGHT RAIN AND LOW-LEVEL MOISTURE. THE PRIMARY
AVIATION CONCERN FOCUSES ON A TIGHTENING SURFACE PRESSURE GRADIENT
AND DEEP MIXING, WHICH WILL GENERATE WIDESPREAD WEST-TO-SOUTHWEST
SURFACE GUSTS OF 25 TO 35 KT THIS AFTERNOON, PARTICULARLY FOR
KMSO, KBTM, AND KSMN. STRENGTHENING FLOW ALOFT INTERACTING WITH
COMPLEX TERRAIN WILL ALSO INCREASE THE RISK FOR MECHANICAL
TURBULENCE AND LOCALIZED MOUNTAIN WAVE ACTIVITY, ESPECIALLY IN
NORTHWEST MONTANA, ALONG THE DIVIDE AND DOWNWIND OF THE BITTERROOT
AND SAPPHIRE RANGES. WHILE SNOW LEVELS REMAIN ABOVE 7,000 FEET,
OBSCURATION OF HIGHER TERRAIN WILL CONTINUE ACROSS NORTHWEST
MONTANA THROUGH THE EVENING. A COLD FRONT WILL PASS ON SATURDAY,
BRINGING A WIND SHIFT, SHOWERS, AND PERIODS OF REDUCED VISIBILITY
AND LOWERED CEILINGS.
MSO WATCHES/WARNINGS/ADVISORIES
MT...NONE.
ID...NONE.
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