948  
FXUS65 KMSO 120715  
AFDMSO  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE MISSOULA MT  
115 AM MDT MON OCT 12 2026  
   
DISCUSSION
 
 
KEY MESSAGES:  
 
- HARD FREEZE COMING FOR THE MORNINGS.  
 
- VALLEY FOG AND STRATUS WILL BE COMMON EARLY THIS WEEK.  
 
- A WARMING AND DRYING TREND THIS WEEK.  
 
- ANOTHER COLD AND COLD FRONT ON THE WAY FOR EARLY NEXT WEEK.  
 
THE WINTER STORM IS WINDING DOWN THIS MORNING AS THE UPPER LEVEL  
LOW OVER THE PACIFIC NORTHWEST IS MIGRATING SOUTH TODAY. EXPECT  
COOL, CLOUDY WEATHER TODAY AS BOTH THE MOISTURE SOURCE AND THE  
SOURCE OF THE COLD AIR ARE CUT OFF FROM THE REGION TODAY. THAT  
BEING SAID, THERE'S QUITE A BIT OF COLD AIR ALREADY IN OUR AREA  
FROM THIS STORM.  
 
DUE TO THE COLD AIR MASS IN PLACE, INCREASING STABILITY, AND A  
DRIER AIR MASS ALOFT MOVING, EXPECT SOME VERY COLD, FOGGY MORNINGS  
AHEAD. THE NEXT FEW MORNINGS WILL BE A BATTLE BETWEEN HOW MUCH IT  
CAN COOL OFF AT NIGHT, AND HOW MUCH FOG AND STRATUS CAN FORM IN  
THE VALLEYS TO KEEP THINGS WARMER. IN ANY CASE, THERE'S PLENTY OF  
POTENTIAL FOR A HARD FREEZE THE NEXT FEW MORNINGS WITH  
TEMPERATURES IN THE LOW TO MID 20S FOR MUCH OF WESTERN MONTANA.  
HOWEVER, DUE TO THE RECENT MOISTURE, AS IT GETS COLD AT NIGHT THAT  
WILL BE LIMITED BY FOG FORMATION. IF THE FOG FORMS, TEMPERATURES  
IN THE MID TO UPPER 20S ARE MORE LIKELY IN THE MORNINGS, BUT IF  
THERE ARE BREAKS IN THE FOG, ESPECIALLY IN THE HIGH ELEVATION  
VALLEYS, THEN IT WILL GET QUITE COLD QUICKLY.  
 
THROUGH THE WEEK A RIDGE WILL BUILD BACK IN OVER THE REGION. THIS  
WILL CAUSE MORE STABLE CONDITIONS, LIMITING HOW QUICKLY FOG CAN  
BURN OFF IN WESTERN MONTANA. CENTRAL IDAHO AND FAR NORTHWEST  
MONTANA PICKED UP FAR LESS MOISTURE FROM THIS RECENT STORM, SO  
THAT WILL BE LESS OF AN IMPACT THERE. HOWEVER, THE BUILDING RIDGE  
WILL CAUSE TEMPERATURES TO RISE TO ABOVE AVERAGE FOR THIS TIME OF  
YEAR BY THE END OF THE WEEK.  
 
ENSEMBLES ARE STARTING TO AGREE ON ANOTHER COLD FRONT FOR EARLY  
NEXT WEEK, SO THE WARMER, DRIER WEATHER AT THE END OF THE WEEK  
WILL ONLY LAST A FEW DAYS. SO FAR ENSEMBLES ARE SHOWING LESS  
POTENTIAL FOR MOISTURE WITH THE NEXT FRONT, ESPECIALLY IF IT COMES  
THROUGH AS AN OPEN WAVE VS A CLOSED LOW LIKE THIS LAST ONE. SO IT  
WONT' BE A REPEAT OF THIS SYSTEM, BUT WILL PROBABLY COME WITH MORE  
WESTERLY WINDS, SOME PRECIPITATION, AND A GOOD COOL DOWN.  
 

 
   
AVIATION
 
CEILINGS AND VISIBILITY WILL BE A CHALLENGE TODAY.  
MANY AREAS HAVE RECEIVED A LOT OF MOISTURE RECENTLY, AND AS THE  
UPPER LEVEL LOW OVER THE PACIFIC NORTHWEST MIGRATES SOUTH A RIDGE  
STARTS TO BUILD OVER THE REGION TODAY. SO EARLY TODAY THE REGION  
WILL BATTLE LOW CLOUDS AND FOG FROM ALL THE RECENT MOISTURE, THEN  
WITH THE INCREASING STABILITY OVERNIGHT AND LATENT MOISTURE, FOG  
WILL CONTINUE TO BE A PROBLEM IN MANY AREA VALLEYS FOR THE NEXT  
FEW DAYS.  
 

 
   
MSO WATCHES/WARNINGS/ADVISORIES
 
 
MT...WINTER WEATHER ADVISORY UNTIL 6 AM MDT EARLY THIS MORNING FOR  
BITTERROOT/SAPPHIRE MOUNTAINS...POTOMAC/SEELEY LAKE  
REGION...WEST GLACIER REGION.  
 
LAKE WIND ADVISORY UNTIL 6 AM MDT EARLY THIS MORNING FOR  
FLATHEAD/MISSION VALLEYS.  
 
WINTER STORM WARNING UNTIL 6 AM MDT EARLY THIS MORNING FOR  
BUTTE/BLACKFOOT REGION.  
 
ID...NONE.  

 
 

 
 
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