216  
FXUS65 KTFX 070944  
AFDTFX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE GREAT FALLS MT  
344 AM MDT MON SEP 7 2026  
   
KEY MESSAGES  
 
- MODERATE TO HEAVY RAIN WILL CONTINUE TO AFFECT MAINLY NORTH  
CENTRAL MONTANA THROUGH TUESDAY MORNING.  
- WARMER AND DRIER CONDITIONS ARRIVE FOR WEDNESDAY AND THURSDAY.  
- ANOTHER COOLER WETTER PERIOD IS EXPECTED FOR FRIDAY AND INTO  
THE WEEKEND.  
 
 
   
DISCUSSION  
 
- METEOROLOGICAL OVERVIEW:  
 
DEEP AND SLOW MOVING UPPER LEVEL LOW PRESSURE WILL CONTINUE TO  
SLOWLY DRIFT EASTWARD OVER THE TREASURE STATE OVER THE NEXT 36-48  
HOURS, BRINGING A PROLONGED PERIOD OF COOL AND WET WEATHER.  
OVERNIGHT SHOWERS AND THUNDERSTORMS THAT MOVED THROUGH THE AREA  
WILL GRADUALLY COALESCE ACROSS NORTH CENTRAL MONTANA AND ALONG THE  
ROCKY MOUNTAIN FRONT, WHERE THEY WILL MORE OR LESS PERSIST  
THROUGH THE DAY TODAY AND INTO EARLY TUESDAY.  
 
A BRIEF PERIOD OF RESPITE FROM THE WET WEATHER WILL ARRIVE  
WEDNESDAY AND THURSDAY AS WEAK UPPER LEVEL RIDGING TRANSITS THE  
AREA. AS THE RIDGE MOVES OVERHEAD, TEMPERATURES WILL BE A BIT  
CLOSER TO AVERAGE, WITH HIGHS GENERALLY IN THE 70S TO LOW 80S  
ACROSS THE LOWER ELEVATIONS. THIS WARMER AND DRIER PERIOD WILL NOT  
LAST LONG, HOWEVER, AS OUR NEXT UPPER LEVEL LOW WILL PUSH IN  
FRIDAY AND SATURDAY, BRINGING ANOTHER PROLONGED PERIOD OF COOLER  
AND WETTER WEATHER.  
 
- FORECAST CONFIDENCE & SCENARIOS:  
 
RAIN THROUGH TUESDAY: MODELS REMAIN IN OVERALL GOOD AGREEMENT  
THAT THE HEAVIEST RAINFALL WILL GENERALLY REMAIN CONFINED TO THE  
ROCKY MOUNTAIN FRONT AND ALONG THE HI-LINE, WHERE AMOUNTS OF 1.5  
TO 3 INCHES OF ADDITIONAL RAINFALL REMAIN POSSIBLE. AREAS THAT  
RECEIVED HEAVY RAINFALL FROM THE STRONG TO SEVERE THUNDERSTORMS  
THAT ROLLED THROUGH THE AREA SUNDAY NIGHT WILL NEED TO BE WATCHED  
EXTRA CLOSELY, AS THIS EXTRA MOISTURE MAY PROVIDE THE ANTECEDENT  
CONDITIONS NEEDED FOR THE RAINFALL TO OVER SATURATE SOME OF THE  
SOILS LOCALLY AND RESULT IN SOME LOCALIZED FLOODING. LUDWIG  
 
 
   
AVIATION  
 
07/00Z TAF PERIOD  
 
MAIN CONCERN THIS AFTERNOON IS STRONG THUNDERSTORMS MOVING ACROSS  
THE REGION FROM THE SOUTHWEST TO THE NORTHEAST WITH SOME BEING  
SEVERE AND CAPABLE OF PRODUCING LARGE HAIL AND WIND GUSTS OF 50  
KT. THESE STORMS WILL PRIMARILY IMPACT KGTF, KHLN, AND KLWT  
HOWEVER KHVR COULD BE IMPACTED IF CONVECTION PERSISTS INTO THE  
NIGHT. MVFR CONDITIONS FOR NORTHERN AND CENTRAL MT WILL CONTINUE  
WITH CHANCES FOR IFR OVERNIGHT AS THE STORM MODE TRANSITIONS TO A  
MORE WIDESPREAD MODERATE TO HEAVY RAIN SYSTEM.  
 
FOR KGTF: SEVERE THUNDERSTORM POTENTIAL WILL BE FROM 01Z TO 02Z  
THIS EVENING. THE PRIMARY HAZARDS EXPECTED WILL BE STRONG GUSTS  
AND A POTENTIAL FOR LARGE HAIL. MVFR CEILINGS WILL RETURN  
OVERNIGHT INTO TOMORROW MORNING ALONG WITH RESTRICTIONS TO  
VISIBILITY DUE TO MODERATE RAIN AND MIST UNTIL LATE TOMORROW  
MORNING. - AKINS  
 
 
   
HYDROLOGY  
 
WHILE AREAS ALONG THE ROCKY MOUNTAIN FRONT HAVE RECEIVED 0.75" TO  
1.5" OF RAINFALL OVER THE PAST DAY OR TWO, THERE HASN'T BEEN MUCH  
OF A RESPONSE IN CREEKS/STREAMS YET DUE TO THE DRIER GROUNDING  
SOAKING ALL THE RAIN UP. THE MAIN CONCERN IS ANOTHER ADDITIONAL  
WIDESPREAD 1 TO 3 INCHES AND ISOLATED 4 INCHES THROUGH TUESDAY  
MORNING ON A MORE SATURATED GROUND. AREAS THAT GET THE HIGHER END  
3 TO 4 INCH TOTALS MAY SEE MINOR OVERFLOW IN CREEKS/STREAMS ALONG  
WITH MUDDIED RURAL ROADS. THE WET CONDITIONS CAN ALSO CAUSE  
ROCK/DEBRIS SLIDES IN THE HIGHER TERRAIN. THEREFORE, A FLOOD WATCH  
WAS ISSUED THROUGH TUESDAY. FARTHER EAST ACROSS NORTH-CENTRAL MT  
WILL SEE WETTING RAIN, BUT CONFIDENCE FOR THOSE HIGHER END TOTALS  
REMAIN LOW. TWO THINGS TO WATCH FOR IS ANY EASTERN SHIFT OF THESE  
AMOUNTS FARTHER EAST ALONG US HIGHWAY 2 TOWARDS HILL COUNTY, AND  
ANY HEAVIER SHOWERS THAT AFFECT AREAS THAT SAW HEAVY RAIN SUNDAY  
NIGHT COULD SEE SOME INCREASED RISK FOR MINOR FLOODING.  
-WILSON/LUDWIG  
 
 
   
PRELIMINARY POINT TEMPS/POPS  
 
GTF 63 46 64 43 / 100 40 70 10  
CTB 56 43 60 43 / 100 90 90 10  
HLN 65 43 68 44 / 100 20 10 0  
BZN 67 39 70 39 / 90 0 0 0  
WYS 60 30 63 30 / 30 0 0 0  
DLN 66 36 70 37 / 40 0 0 0  
HVR 67 46 63 43 / 100 90 100 50  
LWT 67 43 64 41 / 90 20 30 20  
 
 
   
TFX WATCHES/WARNINGS/ADVISORIES  
 
FLOOD WATCH THROUGH TUESDAY MORNING FOR EAST GLACIER PARK REGION-  
EASTERN GLACIER, WESTERN TOOLE, AND CENTRAL PONDERA-EASTERN  
PONDERA AND EASTERN TETON-EASTERN TOOLE AND LIBERTY-NORTHERN  
HIGH PLAINS-SOUTHERN HIGH PLAINS-SOUTHERN ROCKY MOUNTAIN FRONT.  
 
 
 
 
HTTP://WWW.WEATHER.GOV/GREATFALLS  
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