237  
FXUS63 KMPX 171117  
AFDMPX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN  
617 AM CDT SUN AUG 17 2025  
   
KEY MESSAGES
 
 
- ONGOING LINE OF THUNDERSTORMS WILL LEAD TO LOCALIZED AND/OR FLASH  
FLOODING THROUGH SUNRISE.  
 
- SHOWERS AND THUNDERSTORMS POSSIBLE THIS AFTERNOON AND EVENING,  
WITH STRONG WIND GUSTS THE PRIMARY CONCERN.  
 
- QUIET WEATHER RETURNS AFTER MONDAY.  
 

 
   
DISCUSSION
 
 
ISSUED AT 239 AM CDT SUN AUG 17 2025  
 
AN ONGOING LINE OF SHOWERS AND THUNDERSTORMS OVER PORTIONS OF  
SOUTHERN MINNESOTA HAS ALREADY LED TO A FEW FLASH FLOOD WARNINGS,  
WITH RAINFALL RATES EXCEEDING 1 INCH PER HOUR IN SPOTS WITH UP TO 3  
INCHES ALREADY ON THE GROUND AND ANOTHER 1 TO 3 INCHES POSSIBLE  
THROUGH THE NEXT 4 TO 5 HOURS. HIGH RESOLUTION GUIDANCE THIS MORNING  
FAVORS VERY SLOW NORTHWARDS MOVEMENT OF THE LINE OF SHOWERS AND  
STORMS WHICH IS MOST EVIDENT IN THE WESTERN CLUSTER, WITH SHOWERS  
AND STORMS WEAKENING AS THE THERMAL GRADIENT LOOSENS BY SUNRISE.  
PWATS PER RAP/SPC MESOANALYSIS AROUND 2 INCHES ARE PRESENT WHICH  
WILL CONTINUE TO FUEL THE ONGOING ACTIVITY AND ALSO KEEP ANY SEVERE  
WEATHER CONCERNS SUCH AS HAIL ON THE LOWER END OF PROBABILITY.  
MUCAPE CONTINUES TO SIT AROUND 2000-2500 J/KG WITH WEAK DEEP LAYER  
SHEAR, POINTING TOWARDS CONTINUED SLOW MOVING STORMS WITH A  
RELATIVELY LOW RISK OF SEVERE LEVEL THREATS. OTHER THAN A FEW STRONG  
WIND GUSTS, LOCALIZED AND FLASH FLOODING ARE THE MOST LIKELY  
OUTCOMES FROM THIS LINE OF STORMS ALONGSIDE THE FREQUENT LIGHTNING.  
REDEVELOPMENT OF SHOWERS AND STORMS IS POSSIBLE BY MIDDAY AS DAYTIME  
HEATING REPLENISHES INSTABILITY AND SHEAR INCREASES DUE TO THE  
POSITIONING OF THE SURFACE FRONTAL BOUNDARIES AHEAD OF THE SURFACE  
LOW WHICH LOOKS TO MOVE THROUGH OVERNIGHT INTO MONDAY. FORCING LOOKS  
TO BE RELATIVELY WEAK DESPITE THE PRESENT OF A FRONTAL BOUNDARY,  
MAINLY DUE TO THE DE-COUPLING OF THE SHORTWAVE TROUGH WITH THE UPPER  
LEVEL JET, WITH A STRENGTHENING LOW LEVEL JET BEING THE PRIMARY  
FORCING MECHANISM OVERNIGHT.  
 
THE WARM FRONT IS EXPECTED TO LIFT NORTHWARDS AS THE SURFACE LOW  
TRACKS NORTHEAST TOWARDS CENTRAL TO NORTHERN MINNESOTA BY MONDAY  
MORNING, WITH THE COLD FRONT STALLING OVER WESTERN MINNESOTA AROUND  
12Z MONDAY BEFORE MOVING THROUGH DURING THE DAY. THE COLD FRONT WILL  
PRESENT THE FINAL CHANCE FOR SHOWERS AND STORMS FOR THE PERIOD WITH  
BETTER SHEAR ALLOWING FOR THE POTENTIAL FOR ROTATING UPDRAFTS UNLIKE  
THE WEAKER SHEARED ENVIRONMENT THAT PRECEDED IT. BY MONDAY EVENING,  
THE COLD FRONT WILL BE PUSHING THROUGH SOUTHEASTERN MINNESOTA WITH  
THE SURFACE LOW OVER WESTERN WI, ENDING OUR SHOWER AND STORM CHANCES  
BY THAT POINT. TUESDAY AND THE DAYS THAT FOLLOW WILL SEE  
NORTHWESTERLY FLOW ALOFT ALONGSIDE SURFACE HIGH PRESSURE AND  
SUBSIDENCE, WHICH SHOULD KEEP CONDITIONS MUCH QUIETER COMPARED TO  
THE PREVIOUS FEW DAYS. TEMPERATURES WILL REMAIN SEASONAL IN THE  
UPPER 70S TO LOW 80S WITH SUNSHINE RETURNING, WITH THE TRAJECTORY OF  
UPPER LEVEL WINDS LOOKING TO AVOID THE WORST OF THE CANADIAN  
WILDFIRES WHICH HAVE TARNISHED SOME OF THE POTENTIAL BETTER WEATHER  
DAYS OVER THE LAST MONTH.  
 

 
   
AVIATION /12Z TAFS THROUGH 12Z MONDAY/
 
 
ISSUED AT 614 AM CDT SUN AUG 17 2025  
 
ONGOING -RA/-TSRA OVER RWF/MKT WILL GRADUALLY WEAKEN AND MOVE  
OUT AROUND 15-16Z WITH REDEVELOPMENT FOR ALL LOCATIONS GENERALLY  
AFTER 21Z. CAMS HAVE STRUGGLED TO MAINTAIN TIMING THIS MORNING  
WITH THE MOST RECENT RUNS TRENDING LATER WITH -TSRA TIMING LATER  
TODAY. MVFR/IFR CONTINUES DUE TO CIGS AS WE WILL NOT SCATTER OUT  
UNTIL AFTER THE -SHRA/-TSRA IS DONE AFTER THE END OF THE PERIOD.  
WINDS WILL BE BLUSTERY EARLY BEFORE WEAKENING, WITH -TSRA WIND  
GUSTS POTENTIALLY REQUIRED WITHIN THE TEMPO GROUPS WITH FUTURE  
TAF ISSUANCE.  
 
KMSP...LOW MVFR SHOULD GRADUALLY IMPROVE WITH A SLIGHT RISE IN  
CLOUD LEVELS THROUGH THE AFTERNOON, RETURNING TO LOWER MVFR AS  
-RA/-TSRA ARRIVES AFTER 00Z. THE TIMING IS STILL UNCERTAIN BUT  
THE TEMPO GROUP FROM 03 TO 07Z IS THE CURRENT WINDOW FOR THE  
GREATEST -TSRA IMPACTS.  
 
/OUTLOOK FOR KMSP/  
MON...VFR, CHC MVFR/-TSRA. WIND S TO NW 5-15KTS.  
TUE...VFR. WIND NE 5-10KTS.  
WED...VFR. WIND NE 5KTS.  
 

 
   
MPX WATCHES/WARNINGS/ADVISORIES
 
 
MN...NONE.  
WI...NONE.  
 

 
 

 
 
DISCUSSION...TDH  
AVIATION...TDH  
 
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