313  
FXUS65 KTFX 060002  
AFDTFX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREAT FALLS MT  
602 PM MDT SAT SEP 5 2026  
 
AVIATION SECTION UPDATED.  
   
KEY MESSAGES  
 
- SHOWERS AND THUNDERSTORMS TONIGHT AND SUNDAY, BECOME A MORE  
WIDESPREAD RAINFALL SUNDAY NIGHT INTO MONDAY.  
 
- AN ISOLATED SEVERE STORM POSSIBLE SUNDAY.  
 
- COOL TEMPERATURES TO BEGIN THE WEEK, WITH SOME WARMER AFTERNOON  
TEMPERATURES FOR A FEW DAYS MID WEEK.  
 
 
   
DISCUSSION  
 
/ISSUED 244 PM MDT SAT SEP 5 2026/  
 
- METEOROLOGICAL OVERVIEW:  
A SLOW MOVING UPPER LEVEL LOW WILL REMAIN TO OUR WEST THROUGH  
SUNDAY, BEFORE SLOWLY MOVING EASTWARD SUNDAY NIGHT INTO MONDAY.  
EXPECT WAVES OF SHOWERS/THUNDERSTORMS TO MOVE THROUGH THE CWA FROM  
NOW THROUGH SUNDAY AFTERNOON. THERE IS THE POTENTIAL THAT A FEW  
STORMS COULD BECOME SEVERE ON SUNDAY, THUS MUCH OF THE CWA IS IN A  
MARGINAL RISK FOR SEVERE STORMS. AS THE UPPER LEVEL LOW MOVES  
EASTWARD SUNDAY NIGHT INTO MONDAY, THE SHOWERS WILL CHANGE MORE  
INTO A STRATIFORM RAIN, WITH THE HEAVIEST RAINFALL EXPECTED OVER  
NORTH CENTRAL MT. THERE IS ALSO A MARGINAL RISK FOR EXCESSIVE  
RAINFALL THAT COULD CAUSE FLASH FLOODING SUNDAY NIGHT INTO MON  
OVER NORTH CENTRAL MT.  
 
DRIER AND WARMER CONDITIONS DEVELOP MID WEEK, WITH AFTERNOON  
TEMPERATURES CLOSE TO 10 DEGREES ABOVE NORMAL BY THURSDAY. BY NEXT  
FRIDAY, ANOTHER UPPER LEVEL TROF WILL START TO MOVE SOUTHWARD INTO  
THE PACIFIC NORTHWEST, RESULTING IN A MOIST SOUTHWESTERLY FLOW  
OVER MONTANA. THUS THE CHANCES FOR PRECIPITATION WILL START TO  
INCREASE ONCE AGAIN NEXT FRI/SAT.  
 
- FORECAST CONFIDENCE & SCENARIOS:  
THE MAIN CONCERN ON SUNDAY FOR ANY SEVERE STORMS WILL BE STRONG  
WIND GUSTS. THIS SYSTEM ON SUNDAY WILL NOT BE AS STRONG AS THE  
WEATHER SYSTEM THAT WENT THROUGH THE CWA ON WEDNESDAY, NEVER THE  
LESS, AN ISOLATED SEVERE STORM IS POSSIBLE. ADDITIONALLY, SOME  
STORMS COULD ALSO PRODUCE HEAVY RAINFALL. BY MONDAY NIGHT, THE  
NORTHERN PORTIONS OF NORTH CENTRAL MT COULD HAVE RECEIVED BETWEEN  
1 AND 3 INCHES OF RAINFALL, WITH ISOLATED AMOUNTS NEAR 4 INCHES  
POSSIBLE. OVERALL, FLOODING IS NOT EXPECTED, BUT IN AREAS THAT  
EXCEED 3 INCHES, THE PROBABILITY OF MINOR FLOODING ON SMALL  
STREAMS AND CREAKS STARTS TO INCREASE. BRUSDA  
 
 
   
AVIATION  
 
06/00Z TAF PERIOD  
 
VFR CONDITIONS ARE PREVAILING ACROSS THE REGION CURRENTLY HOWEVER  
LOWER CEILINGS ARE EXPECTED TO DEVELOP TONIGHT AFTER 06/04Z PRIMARILY  
IMPACTING KGTF, KCTB, KHVR, AND KLWT. IFR CONDITIONS WILL OCCUR  
GENERALLY FROM 10Z UNTIL 18Z WITH POTENTIALLY LIFR AT KCTB FROM  
12Z TO 15Z. RAINSHOWERS AND MIST WILL ALSO RESTRICT VISIBILITY  
OVER NORTH AND CENTRAL MT FROM 06Z UNTIL 16Z. SECONDARY HAZARDS  
WILL BE MOUNTAIN OBSCURATION DUE TO CLOUDS, RAIN, AND MIST AS WELL  
AS ICING IN-CLOUD ABOVE FL100 ALONG AND 50 NM EAST OF THE ROCKY  
MTN FRONT.  
 
FOR KGTF: MVFR CONDITIONS FOR LOWER CEILINGS WILL DEVELOP BY 07Z  
AND POTENTIALLY BECOMING IFR TEMPORARILY FROM 11Z TO 14Z. SOME  
UNCERTAINTY IS PRESENT IN THE OVERNIGHT LOW TEMPERATURE AND  
DEWPOINT DEPRESSION WHICH WILL DETERMINE IF CEILINGS BECOME IFR OR  
LIFR FOR THE MORNING. LOW LEVEL NORTHEAST UPSLOPING FLOW WITH  
ADEQUATE MOISTURE IS PRESENT TO PERSIST THESE CONDITIONS UNTIL  
LATE SUNDAY MORNING. - AKINS  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
GTF 50 73 51 64 / 30 10 90 100  
CTB 46 63 46 58 / 90 80 80 90  
HLN 49 77 52 66 / 20 10 70 90  
BZN 46 82 49 70 / 0 0 60 70  
WYS 38 75 40 59 / 0 0 80 60  
DLN 43 80 46 66 / 0 0 70 70  
HVR 51 77 51 69 / 10 50 90 100  
LWT 49 79 50 70 / 0 20 90 90  
 
 
   
TFX WATCHES/WARNINGS/ADVISORIES  
 
 
 
 
HTTP://WWW.WEATHER.GOV/GREATFALLS  
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