331  
FXUS65 KMSO 280930  
AFDMSO  
 
AREA FORECAST DISCUSSION...RESENT  
NATIONAL WEATHER SERVICE MISSOULA MT  
330 AM MDT THU AUG 28 2025  
   
DISCUSSION
 
 
KEY MESSAGES:  
 
- LOCALLY DENSE FOG MAY REDUCE VISIBILITY IN THE VALLEYS OF  
NORTH-CENTRAL IDAHO THIS MORNING.  
 
- WIDESPREAD SHOWERS AND THUNDERSTORMS WILL BE CAPABLE OF RAINFALL  
RATES APPROACHING 0.75 INCH PER HOUR, WITH THE GREATEST  
POTENTIAL IN SOUTHWEST MONTANA THIS AFTERNOON.  
 
- WARMING AND DRYING ANTICIPATED FOR THE WEEKEND.  
 
THIS MORNING: LOCALLY DENSE FOG  
 
LOCALLY DENSE FOG IS POSSIBLE THIS MORNING IN THE VALLEYS OF  
NORTH-CENTRAL IDAHO, WHERE WILDFIRE SMOKE IS COMBINING WITH  
ABUNDANT LOW-LEVEL MOISTURE FROM RECENT RAIN. VISIBILITY MAY DROP  
BELOW A QUARTER-MILE, CREATING HAZARDOUS TRAVEL CONDITIONS. IF YOU  
ENCOUNTER DENSE FOG WHILE DRIVING, SLOW DOWN, USE LOW-BEAM  
HEADLIGHTS, AND INCREASE THE DISTANCE BETWEEN YOUR VEHICLE AND THE  
ONE AHEAD.  
 
TODAY: WIDESPREAD SHOWERS AND LOCALLY HEAVY RAIN  
 
A SLOW-MOVING LOW-PRESSURE SYSTEM WILL BRING WIDESPREAD SHOWERS TO WESTERN  
MONTANA AND NORTH-CENTRAL IDAHO TODAY. THE ATMOSPHERE CONTAINS NEARLY 200%  
OF ITS NORMAL MOISTURE FOR THIS TIME OF YEAR. THIS MEANS ANY STRONGER  
SHOWERS OR THUNDERSTORMS THAT DEVELOP WILL BE CAPABLE OF PRODUCING HEAVY  
RAINFALL, WITH RATES APPROACHING 1.00 INCH PER HOUR. WHILE EXTENSIVE CLOUD  
COVER MAY LIMIT OVERALL THUNDERSTORM DEVELOPMENT, THE HIGHEST POTENTIAL FOR  
THESE HEAVY DOWNPOURS APPEARS TO BE IN A CORRIDOR FROM SOUTHWEST MONTANA  
NORTHWARD TOWARD MISSOULA.  
 
FRIDAY THROUGH THE WEEKEND: DRYING AND WARMING TREND  
 
THE WEATHER PATTERN WILL IMPROVE FOR FRIDAY AND THE WEEKEND AS THE STORM  
SYSTEM DEPARTS AND HIGH PRESSURE BUILDS. THIS WILL BRING A WARMING AND  
DRYING TREND WITH TEMPERATURES RETURNING TO NORMAL. HOWEVER, ENOUGH  
LINGERING MOISTURE WILL REMAIN FOR A CHANCE OF ISOLATED AFTERNOON SHOWERS  
AND THUNDERSTORMS, MAINLY ACROSS NORTHWEST MONTANA ON FRIDAY AND NEAR THE  
CONTINENTAL DIVIDE THROUGH THE WEEKEND.  
 
EARLY NEXT WEEK: UNCERTAIN FORECAST  
 
FORECAST CONFIDENCE DECREASES FOR THE START OF NEXT WEEK. COMPUTER MODELS  
SHOW SIGNIFICANT DISAGREEMENT ON THE TRACK AND TIMING OF THE NEXT  
APPROACHING STORM SYSTEM, LEADING TO AN UNCERTAIN FORECAST FOR MONDAY AND  
BEYOND.  
 

 
   
AVIATION
 
WIDESPREAD SHOWERS EXIST ACROSS MUCH OF WESTERN  
MONTANA AND NORTH CENTRAL IDAHO THIS MORNING, CAUSING WIDESPREAD  
LOWERED CEILINGS AND OBSCURATIONS OF THE HIGHER TERRAIN. LOCALLY  
DENSE FOG IS POSSIBLE IN VALLEYS OF NORTH CENTRAL IDAHO DUE TO  
THE COMBINATION OF SATURATED LOW LEVELS DUE TO ONGOING RAINFALL  
AND SMOKE FROM AREA WILDFIRES. FORECAST MODELS INDICATE  
PRECIPITATION WILL BECOME MORE CONVECTIVE THIS AFTERNOON, WITH  
LIGHTNING AND VERY HEAVY RAINFALL RATES BEING THE MAIN CONCERN.  
THE HIGHEST PROBABILITY FOR LIGHTNING EXISTS FOR KBTM (30 PERCENT  
CHANCE BY 28/2300Z) AND KMSO (20 PERCENT CHANCE BY 28/2300Z).  
 

 
   
MSO WATCHES/WARNINGS/ADVISORIES
 
 
MT...NONE.  
ID...NONE.  

 
 

 
 
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