224  
FXUS63 KMPX 132346  
AFDMPX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN  
646 PM CDT SUN SEP 13 2026  
   
KEY MESSAGES  
 
- WIDESPREAD RAIN ARRIVES MONDAY WITH ADDITIONAL CHANCES LATER  
IN THE WEEK.  
 
- A COOLER PATTERN HAS ARRIVED WITH HIGHS IN THE 60S TO LOW 70S  
THROUGH NEXT WEEK.  
 
 
   
DISCUSSION  
 
ISSUED AT 215 PM CDT SUN SEP 13 2026  
 
NOW THAT THE CLOUDS ARE CLEARING, WE'VE GET A SPECTACULAR FALL  
WEATHER DAY WITH HIGH PRESSURE THAT CAME OUT OF THE CANADIAN ROCKIES  
MOVING OVERHEAD. HOWEVER, ALL ONE NEEDS TO DO IS LOOK AT THE H5 LOW  
OVER THE NORTHWEST CONUS TO SEE WHAT WILL BRING THIS PLEASANT  
WEATHER TO AN END ON MONDAY.  
 
TONIGHT, WE'LL BE UNDER THE INFLUENCE OF THE SURFACE HIGH. CLOUD  
COVER WILL MOVE INTO WESTERN MN, BUT SKIES WILL REMAIN CLEAR IN  
WESTERN WI, WHICH WILL SETUP A DECENT GRADIENT IN LOWS TONIGHT, WITH  
CLOUDS KEEPING TEMPERATURES UP IN THE 50S IN WESTERN MN, BUT THE  
CLEAR SKIES AND LIGHT WINDS ALLOWING FOR SOME PLACES OUT AROUND  
MORA, RICE LAKE, AND LADYSMITH TO DROP INTO THE UPPER 30S. GIVEN  
CURRENT FORECAST LOWS WITH ISOLATED UPPER 30S, THERE'S NO NEED FOR  
ANY FROST HEADLINES IN THE MPX AREA AT THIS TIME.  
 
FOR MONDAY, THE H5 LOW CURRENTLY OUT AROUND IDAHO WILL DEEPEN WHILE  
MOVING TO ALONG THE NODAK/CANADA BORDER. A LEAD SHORTWAVE AHEAD OF  
THIS LOW WILL TAKE ON A NEGATIVE TILT, WITH H85 WINDS RESPONDING  
ACCORDINGLY, GETTING UP OVER 50 KTS AS THE LLJ MOVES ACROSS THE  
UPPER MS VALLEY. PWATS WILL INCREASE TO AROUND 1.8", WHICH IS  
PUSHING NEAR THE TOP OF CLIMATOLOGY FOR THIS POINT IN SEPTEMBER.  
WITH THAT KIND OF MOISTURE AND THE STRONG LLJ ALREADY NOTED, IVT  
VALUES ARE NEAR CLIMATOLOGY MAX AS WELL. THIS WILL SUPPORT SOME  
EFFICIENT RAIN PRODUCERS, BUT THAT LACK OF INSTABILITY WILL REALLY  
LIMIT THE HEAVY RAIN THREAT ON MONDAY. THE MAIN UNCERTAINTY FOR  
TOMORROW DEALS WITH WHERE THE HEAVIEST RAIN FALLS, MOST OF THE  
GUIDANCE SHOWS A LARGE BAND OF 1-1.5" INCHES OF RAIN FALLING WITH  
THIS LLJ FORCED RAINFALL, BUT PLACEMENT OF THAT BAND RANGES FROM  
WEST CENTRAL THROUGH CENTRAL MN AND SOUTH CENTRAL MN THROUGH WESTERN  
WI. WITH THE UNCERTAINTY IN PLACEMENT OF THE HEAVIEST RAIN, WE STUCK  
WITH THE NBM FOR NOW, WHICH FAVORS THE NORTHERN SOLUTION. WHAT WE  
DID CHANGE FROM THE NBM WERE THE HIGHS MONDAY. WE TOOK A GOOD 5-10  
DEGREES OFF OF NBM HIGHS FOR MONDAY, WITH CLOUD COVER AND RAIN  
HOLDING HIGHS BACK IN THE 60S FOR MOST OF THE MPX AREA.  
 
GOING INTO MONDAY NIGHT, THE LLJ AND PLUME OF HIGH PWATS WILL  
CONTINUE SHIFTING EAST, LARGELY MOVING EAST OF THE MPX AREA. EVEN  
THOUGH THE SURFACE COLD FRONT WILL BE LAGGING TO THE WEST OF THE  
DEEPER MOISTURE PLUME, THE FACT THAT THE LLJ AND PLUME OF HIGH PWAT  
AIR MOVES EAST OF THE MPX AREA MEANS THAT THE NEXT ROUND OF HEAVY  
RAIN AND STORMS THAT DEVELOPS MONDAY EVENING THROUGH MONDAY NIGHT  
WILL BE LARGELY EAST OF THE MPX AREA, FALLING ALONG AND EAST OF A  
LINE FROM ROUGHLY OMAHA NEBRASKA TO WAUSAU, WI.  
 
NEXT WEEK, THIS FRONT WILL RUN INTO AN UNSEASONABLY STRONG BLOCKING  
HIGH OVER THE SOUTHEAST CONUS. THIS WILL CAUSE THE FRONT TO STALL  
OUT FROM LOWER MO RIVER VALLEY TO BETWEEN THE GREAT LAKES AND OHIO  
VALLEY. WE'LL SEE MULTIPLE WAVE RIPPLE ACROSS THIS FRONT THROUGH THE  
WEEK. THE FIRST ONE COMES TUESDAY NIGHT THROUGH WEDNESDAY NIGHT.  
THIS LOOKS TO LARGELY IMPACT NORTHEAST KS TO SOUTHERN LAKE MICHIGAN,  
THOUGH THE NORTHERN FRINGE OF THIS RAIN SHIELD DOES LOOK TO GET UP  
INTO AT LEAST SOUTHERN MN, WHICH DRIVES THE POPS WEDNESDAY AFTERNOON  
THROUGH WEDNESDAY NIGHT THAT ARE HIGHEST ACROSS SOUTH CENTRAL AND  
SOUTHEAST MN. THE NEXT WAVE ARRIVES FOR FRIDAY INTO SATURDAY AND  
THIS ONE LOOKS TO TAKE A MORE NORTHERLY TRACK, BRINGING BETTER  
PRECIPITATION CHANCES TO THE MPX AREA. WE'RE AGAIN SEEING MODELS  
PUMPING OUT ANOTHER 1+" RAIN EVENT WITH THIS SYSTEM, SO THERE'S  
POTENTIAL FOR SOME BENEFICIAL RAINS TO BOTH BEGIN AND END THE WORK  
WEEK.  
 
NEXT WEEKEND, CONFIDENCE IN THE FORECAST, AT LEAST FOR PRECIPITATION  
CHANCES, DROPS OFF. THE INTENSE SOUTHERN RIDGE WILL FINALLY START TO  
BREAK DOWN AS A SLOW MOVING LONG WAVE TROUGH MOVES ACROSS THE NORTH  
CENTRAL CONUS. THE NBM POPS ARE UNDER 20%, BUT THE CANADIAN AND  
ECMWF ARE STARTING TO COME AROUND ON THE IDEA OF A STRONGER WAVE  
EMBEDDED WITHIN THIS TROUGH DRIVING ANOTHER CHANCE OF RAIN ACROSS  
THE REGION SUNDAY/SUNDAY NIGHT, SO IT'S LIKELY THAT WE'LL START  
SEEING POPS INCREASE FOR THE END OF NEXT WEEKEND AS THE NBM STARTS  
PICKING UP ON THIS NEWER DEVELOPMENT IN THE MODELS.  
 
 
   
AVIATION /00Z TAFS THROUGH 06Z TUESDAY/  
 
ISSUED AT 627 PM CDT SUN SEP 13 2026  
 
VFR CONDITIONS CONTINUE THROUGH THE EVENING AND OVERNIGHT WITH  
LIGHT AND VRB WINDS. WINDS WILL BECOMING SOUTHEASTERLY DURING  
THE EARLY MORNING HOURS AS THE NEXT STORM SYSTEM MOVES ACROSS  
THE AREA ON MONDAY. A BAND OF PRECIPITATION WILL MOVE SW TO NE  
ACROSS THE FORECAST DURING THE MORNING AND AFTERNOON HOURS, WITH  
PRECIPITATION STARTING ACROSS WEST/SOUTHWEST MN BETWEEN 12-14Z  
BEFORE TRACKING EAST/NORTHEAST THROUGH THE MORNING. PRECIP  
COVERAGE WILL BE WIDESPREAD WITH MODERATE RAINFALL RATES AT  
TIMES. MVFR CIGS CAN BE EXPECTED AS WELL DURING THE DURATION OF  
PRECIPITATION, WITH ISOLATED INSTANCE OF IFR. WINDS WILL BE  
GUSTY AS, WITH GUSTS UP TO 30 KNOTS POSSIBLE.  
 
KMSP...ONLY CONCERN IS THE ARRIVAL OF PRECIP DURING THE MORNING  
ON MONDAY AS WELL AS GUSTY SE'LY WINDS. PREVAILING LIGHT RAIN  
TO START AS EARLY AS 15Z WITH MODERATE RAINFALL FALLING BETWEEN  
16-20Z. LIGHT RAIN SHOWERS WILL LINGER BEYOND THE MODERATE RAIN  
RATE WINDOW THROUGH 00Z. CIGS FALL TO MVFR HEIGHTS BY TOMORROW  
EVENING. WINDS WILL BE OUT OF THE NW FOR THE REMAINDER OF TODAY  
AND BECOMING LIGHT AND VARIABLE OVERNIGHT. WINDS SHIFT SE'LY  
TOMORROW MORNING WITH SPEEDS INCREASING TO 25-30KTS AS EARLY AS  
16Z.  
 
/OUTLOOK FOR KMSP/  
TUE...VFR. WIND NW 10-15KTS.  
WED...VFR. CHC MVFR/-SHRA PM. WIND E 5-10KTS.  
THU...VFR. CHC MVFR/-SHRA AM. WIND E 5-10KTS.  
 
 
   
MPX WATCHES/WARNINGS/ADVISORIES  
 
MN...NONE.  
WI...NONE.  
 
 
 
 
 
DISCUSSION...MPG  
AVIATION...LPR  
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