210
FXUS65 KMSO 111820
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
1220 PM MDT SAT JUL 11 2026
DISCUSSION
KEY MESSAGES:
- WARMEST TEMPERATURES OF THE SUMMER THIS WEEKEND THROUGH EARLY
NEXT WEEK. ELEVATED HEAT RISK FOR THOSE SENSITIVE TO HEAT,
ESPECIALLY THOSE WITHOUT COOLING OR HYDRATION.
- LOW RELATIVE HUMIDITY AND INCREASED WEST WINDS WILL RESULT IN
ELEVATED FIRE WEATHER CONCERNS TODAY AND CRITICAL FIRE WEATHER
CONCERNS SUNDAY IN SOUTHWEST MONTANA.
- A SURGE OF SUMMER MOISTURE WILL BRING CLOUDS, SHOWERS, AND
THUNDERSTORMS BY LATE MONDAY AND INTO TUESDAY.
HOT AFTERNOON TEMPERATURES WILL PREVAIL ACROSS THE NORTHERN
ROCKIES TODAY, AND AGAIN ON SUNDAY, EXTENDING INTO MONDAY FOR
SOME. WE ARE NOT EXPECTING RECORD TEMPERATURES ACROSS THE REGION,
THOUGH THEY WILL BE RUNNING 10 TO 15 DEGREES ABOVE NORMAL. AMONG
MAJOR POPULATION AREAS, BUTTE MAY COME CLOSEST WITH A FORECAST
HIGH OF 92 TODAY AND 93 ON SUNDAY, BOTH DAYS WITHIN 5 DEGREES OF A
RECORD. HEAT ADVISORIES REMAIN IN EFFECT FOR THE HELLS CANYON
AREA AND THE LOWER SALMON RIVER VALLEYS IN LEMHI COUNTY TODAY
THROUGH SUNDAY EVENING. MODERATE HEAT IMPACTS ARE EXPECTED FOR
VALLEYS ALONG AND EAST OF HIGHWAY 93, MEANING INDIVIDUALS
SENSITIVE TO HEAT MAY BE AFFECTED.
IN ADDITION TO THE HEAT, STRONG WINDS ABOVE THE SURFACE COMBINED
WITH LOW DAYTIME HUMIDITY WILL CREATE NEAR-CRITICAL FIRE WEATHER
CONDITIONS IN SOUTHWEST MONTANA TODAY, WHICH WILL BECOME CRITICAL
FOR SUNDAY. MINIMUM RELATIVE HUMIDITY VALUES WILL RANGE BETWEEN 8
AND 15% ALONG WITH WESTERLY WIND GUSTS BETWEEN 30 AND 40 MPH
STARTING AFTER NOON ON SUNDAY. AS SUCH, THE FIRE WEATHER WATCH FOR
THE EAST BEAVERHEAD NATIONAL FOREST HAS BEEN UPGRADED TO A RED
FLAG WARNING FOR SUNDAY AFTERNOON. THIS INCLUDES AREAS ALONG AND
EAST OF I-15 IN SOUTHWEST MONTANA. WE WILL CONTINUE TO MONITOR
WEATHER CONDITIONS AND COORDINATE WITH OUR NATIONAL FOREST
PARTNERS ON POTENTIAL UPGRADES TO THE WATCH FOR THE DEERLODGE/WEST
BEAVERHEAD NATIONAL FOREST.
FOR THOSE RECREATING OUTDOORS THIS WEEKEND, PLEASE PRIORITIZE
SAFETY: STAY CONSISTENTLY HYDRATED, TAKE FREQUENT BREAKS IN THE
SHADE, AVOID STRENUOUS ACTIVITIES DURING PEAK AFTERNOON HEATING,
AND PRACTICE EXTREME CAUTION TO PREVENT ANY SPARKS OR FIRE STARTS
IN THESE DRY, WINDY CONDITIONS.
A SURGE OF MOISTURE IS STILL EXPECTED TO MOVE INTO THE REGION FROM
THE SOUTH, ELEVATING THE RISK FOR SHOWERS AND THUNDERSTORMS ACROSS
WESTERN MONTANA AND NORTH-CENTRAL IDAHO ON MONDAY, BRINGING RELIEF
FROM THE HOT AND DRY WEEKEND CONDITIONS. THE INITIAL SHOWER AND
THUNDERSTORM ACTIVITY WILL BRING MOSTLY CLOUDY SKIES AND ERRATIC,
GUSTY WINDS DUE TO THE VERY DRY AIR AT THE SURFACE. BY TUESDAY
EVENING, THE ATMOSPHERE WILL MOISTEN ENOUGH FOR RAIN TO REACH THE
GROUND.
ATMOSPHERIC CONDITIONS ARE BECOMING MORE FAVORABLE FOR THE
POTENTIAL OF A FEW SEVERE THUNDERSTORMS BY WEDNESDAY AND INTO
THURSDAY. IF YOU HAVE OUTDOOR PLANS THROUGH MID-WEEK, PLEASE PLAN
ACCORDINGLY.
AVIATION
VFR CONDITIONS WILL PREVAIL ACROSS WESTERN MONTANA AND
NORTH-CENTRAL IDAHO THROUGH THE FORECAST PERIOD. THE PRIMARY
OPERATIONAL CONCERNS THIS AFTERNOON ARE INCREASED WINDS AND HIGH
DENSITY ALTITUDES ACROSS ALL TERMINALS (KMSO, KGPI, KHRF, KBTM,
KSMN). STRONG SOLAR HEATING IS MAXIMIZING ATMOSPHERIC MIXING.
ANTICIPATE SUSTAINED WESTERLY TO SOUTHWESTERLY SURFACE WINDS
INCREASING TO 15-20 KNOTS ACROSS REGIONAL TERMINALS THROUGH 03Z,
WITH LOCALIZED GUSTS UP TO 25 KNOTS.
MSO WATCHES/WARNINGS/ADVISORIES
MT... RED FLAG WARNING FROM NOON TO 9 PM MDT SUNDAY FOR EAST
BEAVERHEAD.
FIRE WEATHER WATCH FROM SUNDAY AFTERNOON THROUGH SUNDAY EVENING
FOR DEERLODGE/WEST BEAVERHEAD.
ID...HEAT ADVISORY UNTIL 9 PM MDT /8 PM PDT/ SUNDAY FOR EASTERN LEMHI
COUNTY...SOUTHERN CLEARWATER MOUNTAINS...WESTERN LEMHI
COUNTY.
HEAT ADVISORY UNTIL 8 PM PDT SUNDAY FOR LOWER HELLS
CANYON/SALMON RIVER REGION.
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