871  
FNUS75 KMSO 200219  
FWSMSO  
 
SPOT FORECAST FOR MACALLISTER FIRE  
NATIONAL WEATHER SERVICE MISSOULA MT  
819 PM MDT TUE AUG 19 2025  
 
FORECAST IS BASED ON FORECAST START TIME OF 2200 MDT ON AUGUST 19.  
IF CONDITIONS BECOME UNREPRESENTATIVE...CONTACT THE NATIONAL WEATHER  
SERVICE.  
   
..RED FLAG WARNING IN EFFECT FROM 1 PM TO 10 PM MDT WEDNESDAY  
 
   
DISCUSSION  
SOUTH WINDS CONTINUE OVERNIGHT WITH ONLY MODEST RH  
RECOVERY. WEDNESDAY WILL BE HOT AND DRY ONCE AGAIN, IT WILL BE  
VERY UNSTABLE WITH DEEP MIXING AND GUSTY SOUTHWESTERLY WINDS THUS  
CRITICAL FIRE WEATHER CONDITIONS ARE EXPECTED. THERE IS A SLIGHT  
CHANCE OF SHOWERS AND THUNDERSTORMS ON WEDNESDAY AFTERNOON WITH  
GUSTY, ERRATIC WINDS A CONCERN.  
 
WINDS SHIFT TO NORTHERLY ON WEDNESDAY NIGHT AND CONTINUE FOR  
SEVERAL DAYS. DAYTIME TEMPERATURES COOL ON THURSDAY WITH SOMEWHAT  
IMPROVED MIN RH.  
 
   
REST OF TONIGHT  
 
* SKY/WEATHER.........MOSTLY CLEAR.  
* CWR (> 0.10 INCH)...0 PERCENT.  
* CHANCE LIGHTNING....0 PERCENT.  
* MIN TEMPERATURE.....57-62.  
* MAX HUMIDITY........40-45 PERCENT.  
* WIND (20 FT)........SOUTH TO SOUTHWEST 10-16 MPH.  
* MIXING HEIGHT.......500 FT AGL.  
* MIXING WINDS........SOUTH 15 MPH.  
* PRECIP AMOUNT.......0.00 INCHES.  
   
WEDNESDAY  
 
* SKY/WEATHER.........PARTLY CLOUDY. SLIGHT CHANCE OF SHOWERS AND  
THUNDERSTORMS IN THE AFTERNOON.  
* CWR (> 0.10 INCH)...10 PERCENT.  
* CHANCE LIGHTNING....15 PERCENT.  
* MAX TEMPERATURE.....86-91.  
* MIN HUMIDITY........21-26 PERCENT.  
* WIND (20 FT)........SOUTH 8-13 MPH SHIFTING TO THE SOUTHWEST  
9-15 MPH IN THE AFTERNOON. GUSTS TO 30 MPH IN THE AFTERNOON.  
* MIXING HEIGHT.......2000 FT AGL INCREASING TO 14000 FT AGL IN  
THE AFTERNOON.  
* MIXING WINDS........SOUTHWEST 15 MPH.  
* PRECIP AMOUNT.......0.00-0.15 INCHES.  
   
WEDNESDAY NIGHT  
 
* SKY/WEATHER.........PARTLY CLOUDY.  
* CWR (> 0.10 INCH)...0 PERCENT.  
* CHANCE LIGHTNING....0 PERCENT.  
* MIN TEMPERATURE.....52-57.  
* MAX HUMIDITY........71-76 PERCENT.  
* WIND (20 FT)........NORTH 6-13 MPH.  
* MIXING HEIGHT.......1000 FT AGL DECREASING TO 500 FT AGL IN THE  
LATE EVENING AND OVERNIGHT.  
* MIXING WINDS........NORTH 10 MPH.  
* PRECIP AMOUNT.......0.00 INCHES.  
   
THURSDAY  
 
* SKY/WEATHER.........MOSTLY SUNNY.  
* CWR (> 0.10 INCH)...0 PERCENT.  
* CHANCE LIGHTNING....0 PERCENT.  
* MAX TEMPERATURE.....78-83.  
* MIN HUMIDITY........28-33 PERCENT.  
* WIND (20 FT)........NORTHWEST 6-7 MPH SHIFTING TO THE NORTH  
AROUND 10 MPH IN THE AFTERNOON. GUSTS TO 17 MPH IN THE  
AFTERNOON.  
* MIXING HEIGHT.......3000 FT AGL INCREASING TO 8500 FT AGL IN THE  
AFTERNOON.  
* MIXING WINDS........NORTHWEST 10 MPH.  
* PRECIP AMOUNT.......0.00 INCHES.  
   
FORECAST DAYS 3 THROUGH 5  
   
FRIDAY  
 
MOSTLY CLEAR. LOWS 49-54. HIGHS 76-81. NORTH WINDS 6-15 MPH.    
SATURDAY  
 
MOSTLY CLEAR. LOWS 47-52. HIGHS 78-83. NORTH WINDS 6-15 MPH.    
SUNDAY  
 
PARTLY CLOUDY. LOWS 50-55. HIGHS 79-84. NORTH WINDS 6-13 MPH.  
 
 
FORECASTER...BOOTH  
REQUESTED BY...BOB CULBRETH  
TYPE OF REQUEST...WILDFIRE  
.TAG 2520121.2/MSO  
.DELDT 08/19/25  
.FORMATTERVERSION 2.0.0  
.EMAIL BOB.CULBRETH@MT.GOV  
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