845
FXUS65 KMSO 110850
AFDMSO
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE MISSOULA MT
150 AM MST SUN JAN 11 2026
DISCUSSION
KEY MESSAGES:
- HIGH PRESSURE TO BRING PROLONGED DRY PATTERN NEXT 7-10 DAYS.
- RISK FOR LIGHT FREEZING RAIN EVENT ACROSS LINCOLN COUNTY LATE
SUNDAY NIGHT INTO MONDAY MORNING.
CONFIDENCE IS HIGH FOR A PROLONGED PERIOD OF RELATIVELY MILD AND
DRY CONDITIONS ACROSS THE NORTHERN ROCKIES FOR THE NEXT 7-10 DAYS.
GLOBAL ENSEMBLES ARE IN STRONG AGREEMENT FOR A HIGH AMPLITUDE
RIDGE OF HIGH PRESSURE TO REMAIN ANCHORED ALONG THE U.S. WEST
COAST, WITH THE STORM TRACK POSITIONED WELL TO THE NORTH. MILD
TEMPERATURES ARE EXPECTED ACROSS THE MIDSLOPES AND MOUNTAIN AREAS,
WHILE VALLEYS CONTINUE TO EXPERIENCE INVERTED CONDITIONS. VALLEY
FOG AND STRATUS HAVE BEEN ISOLATED THUS FAR AND THIS TREND WILL
CONTINUE INTO MONDAY AS WAVES OF MID-UPPER LEVEL CLOUD COVER
STREAM IN FROM THE NORTH-NORTHWEST. THIS CLOUD COVER WILL REDUCE
OVERNIGHT RADIATIONAL COOLING, DISRUPTING THE DEVELOPMENT OF
WIDESPREAD STRATUS AND FOG.
THE MAIN PERIOD TO WATCH FOR NOTABLE WEATHER IMPACTS IS LATE
SUNDAY NIGHT INTO MONDAY MORNING. MODELS SUGGEST LINCOLN AND
FLATHEAD COUNTIES IN NORTHWEST MONTANA WILL BE ON THE SOUTHERN
MOST EXTENT OF A PLUME OF PACIFIC MOISTURE MOVING ACROSS SOUTHERN
CANADA. MODELS HAVE BEEN TRENDING DOWNWARD WITH PRECIPITATION
AMOUNTS THE LAST FEW DAYS WITH THIS FEATURE, WITH FORECAST AMOUNTS
OF A TRACE TO 0.03 INCHES IN THE VALLEYS AND UP TO 0.20 INCHES IN
THE HIGHER TERRAIN. NONETHELESS, WITH INVERSIONS IN PLACE AND
SNOW LEVELS FORECAST TO RISE NEAR 5,000-6,000 FEET, LIGHT FREEZING
RAIN IS A CONCERN, MAINLY FOCUSED FOR AREAS NORTH OF US-2 AND
WEST OF US-93 IN LINCOLN COUNTY.
THE RIDGE AXIS WILL SHIFT FURTHER EASTWARD TUESDAY INTO WEDNESDAY.
STAGNANT CONDITIONS WILL HELP TO STRENGTHEN VALLEY INVERSIONS,
INCREASING THE RISK FOR AREAS OF FOG AND STRATUS.
AVIATION
VALLEY INVERSIONS WILL CONTINUE THROUGH SUNDAY. EXPECT VFR
CONDITIONS FOR MOST LOCATIONS. DRIER SURFACE CONDITIONS AND WAVES
OF MID-UPPER LEVEL CLOUD COVER WILL HELP TO REDUCE THE DEVELOPMENT
OF WIDESPREAD VALLEY FOG AND STRATUS. ISOLATED AREAS OF FOG WILL
DEVELOP NEAR BODIES OF WATER AND RIVERS, WITH A 10-20% CHANCE FOR
PERIODS OF VISIBILITY BELOW 2SM FOR KGPI AND KMSO THROUGH
11/1600Z.
MSO WATCHES/WARNINGS/ADVISORIES
MT...NONE.
ID...NONE.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page