320
FXUS65 KMSO 161012
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
412 AM MDT TUE JUN 16 2026
DISCUSSION
KEY MESSAGES:
- STRONG WINDS GUSTING 40 TO 50 MPH TODAY ACROSS MUCH OF WESTERN
MONTANA AND NORTH-CENTRAL IDAHO.
- 70 PERCENT CHANCE FOR WINDS BRIEFLY EXCEEDING 50 MPH IN THE
PINESDALE AREA OF THE WESTERN BITTERROOT VALLEY, 85 PERCENT
CHANCE IN ANACONDA LATER TODAY. ISOLATED TREE DAMAGE POSSIBLE.
- MODERATE HEAT RISK IN THE LOWER VALLEYS OF NORTH-CENTRAL IDAHO
AS HIGHS COULD REACH UPPER 90S TO LOW 100S FRIDAY.
- SURGE OF MONSOON MOISTURE COULD BRING SHOWERS AND THUNDERSTORMS
CAPABLE OF HEAVY RAIN FRIDAY NIGHT INTO SATURDAY LEMHI COUNTY
TO SOUTHWEST MONTANA.
NO SIGNIFICANT CHANGES EXPECTED TODAY. STRONG WESTERLY WINDS
GUSTING 30 TO 45 MPH WITH ISOLATED HIGHER GUSTS ARE STILL ON TAP
ACROSS WESTERN MONTANA AND LEMHI COUNTY. ANTICIPATED IMPACTS
INCLUDE HAZARDOUS BOATING CONDITIONS ON AREA LAKES, CROSSWINDS
AFFECTING HIGH- PROFILE VEHICLES, AND POTENTIAL TREE DAMAGE
LEADING TO LOCALIZED POWER OUTAGES. FURTHERMORE, THE HOT, DRY, AND
WINDY ENVIRONMENT WILL GENERATE ELEVATED FIRE WEATHER CONCERNS
ACROSS SOUTHWEST MONTANA.
A WEAK, DRY COLD FRONT WILL ADVANCE FROM NORTH TO SOUTH ACROSS THE
REGION THIS EVENING, ACCOMPANIED BY BROAD, MODEST SURFACE
PRESSURE RISES AFTER 6 PM MDT. COLD AIR ADVECTION ALOFT WILL
INTENSIFY MID- LEVEL, RIDGE-TOP WINDS TO NEAR 60 MPH ACROSS WEST-
CENTRAL MONTANA, INDUCING ELEVATED MOUNTAIN WAVES. HIGH-RESOLUTION
GUIDANCE SUGGESTS THE STRONGEST DOWNWARD MOMENTUM WILL LIKELY
REMAIN ABOVE THE VALLEY FLOORS, HINDERED BY A DEVELOPING STABLE
NOCTURNAL LAYER AND A LACK OF PRECIPITATION OR VIRGA TO FACILITATE
DOWNWARD MOMENTUM TRANSPORT. HOWEVER, LOCALIZED SEVERE GUSTS
REMAIN POSSIBLE. CONCURRENTLY, ISOLATED SHOWERS AND THUNDERSTORMS
MAY INITIATE OVER THE CONTINENTAL DIVIDE IN GLACIER NATIONAL
PARK, POSING LOCALIZED THREATS OF LIGHTNING, SMALL HAIL, AND GUSTY
OUTFLOW WINDS.
WEDNESDAY WILL BRING TEMPERATURES 5 TO 10 DEGREES COOLER, RETURNING
THE REGION TO NEAR-SEASONAL NORMALS. THE DEPARTING SHORTWAVE WILL
FOCUS SCATTERED SHOWERS AND THUNDERSTORMS ACROSS NORTHWEST
MONTANA ALONG THE CONTINENTAL DIVIDE, WHILE THE REMAINDER OF THE
REGION STAYS DRY. UPPER LEVEL RIDGING WILL AMPLIFY THURSDAY AND
FRIDAY, DRIVING TEMPERATURES BACK TO OR SLIGHTLY ABOVE TUESDAY'S
VALUES. LOWER VALLEYS IN NORTH-CENTRAL IDAHO ARE FORECAST TO REACH
THE LOW 100S BY FRIDAY, CARRYING AN 80 PERCENT PROBABILITY OF
REACHING MODERATE HEATRISK AND POSING A THREAT TO VULNERABLE
POPULATIONS LACKING ADEQUATE COOLING OR HYDRATION.
ANOTHER UPPER-LEVEL DISTURBANCE WILL APPROACH LATE FRIDAY INTO
SATURDAY, REINTRODUCING WIND AND PRECIPITATION CHANCES.
THUNDERSTORM PROBABILITIES WILL INCREASE BY SATURDAY, PARTICULARLY
ALONG AND SOUTH OF THE INTERSTATE 90 CORRIDOR.
AVIATION
STRONG WESTERLY WINDS ARE EXPECTED TO DEVELOP AFTER
16/1800Z/1200MDT TODAY. SUSTAINED WINDS OF 15 TO 25 KTS AND GUSTS
REACHING 40KTS WILL BE POSSIBLE IN THE AFTERNOON, THROUGH
17/0000Z/1800MDT. ISOLATED SHOWERS AND THUNDERSTORMS WILL BE
POSSIBLE IN THE TERRAIN ALONG THE CONTINENTAL DIVIDE FROM
16/2200Z/1500MDT TO 17/0300Z/2100MDT. THE CONVECTION WILL BE
CAPABLE OF MIXING DOWN STRONG AND ERRATIC WINDS, AND SMALL HAIL.
MSO WATCHES/WARNINGS/ADVISORIES
MT...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM MDT THIS EVENING
FOR FLATHEAD/MISSION VALLEYS...KOOTENAI/CABINET REGION...
LOWER CLARK FORK REGION...MISSOULA/BITTERROOT VALLEYS...
POTOMAC/SEELEY LAKE REGION...WEST GLACIER REGION.
WIND ADVISORY FROM 1 PM THIS AFTERNOON TO MIDNIGHT MDT TONIGHT
FOR BITTERROOT/SAPPHIRE MOUNTAINS...BUTTE/BLACKFOOT REGION.
ID...WIND ADVISORY FROM 1 PM THIS AFTERNOON TO 10 PM MDT THIS EVENING
FOR EASTERN LEMHI COUNTY...WESTERN LEMHI COUNTY.
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