082  
FXUS63 KMPX 210410  
AFDMPX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN  
1110 PM CDT WED OCT 20 2021  
   
UPDATED FOR 06Z AVIATION DISCUSSION
 
 
ISSUED AT 1107 PM CDT WED OCT 20 2021  
 

 
   
SHORT TERM
 
(THIS EVENING THROUGH THURSDAY NIGHT)  
ISSUED AT 225 PM CDT WED OCT 20 2021  
 
AN ARC OF SHOWERS AND THUNDERSTORMS ACROSS NORTHERN SD INTO  
CENTRAL/EASTERN MN AND WESTERN WI IS BECOMING A DEFORMATION BAND  
WHILE A DRY SLOT ADVANCES NORTH TOWARD ST. CLOUD AND ALEXANDRIA. A  
FEW OF THE STORMS ON THE WARMER SIDE OF THE SYSTEM (EASTERN MN) HAVE  
BEEN STRONG WITH SOME SMALL HAIL, BUT HAVE REMAINED WELL BELOW SEVERE  
LIMITS. THE DRY SLOT WILL FILL IN WITH ADDITIONAL SHOWERS AS THE LOW  
CONTINUES EAST ACROSS SOUTHERN MN. MAINTAINED 80-100% POPS THROUGH  
THE EVENING BEFORE THE SHOWERS ARE EXPECTED TO END FROM WEST TO EAST  
OVERNIGHT.  
 
CLOUDS WILL LINGER BEHIND THE SHOWERS FOR SEVERAL HOURS, BUT MID  
LEVEL RIDGING AND MUCH DRIER AIR WILL BRING THE BACK EDGE OF THE  
LOW CLOUD COVER THROUGH THE REGION THURSDAY MORNING. SCATTERED HIGH  
CLOUDS COULD CONTINUE FOR THE REMAINDER OF THE SHORT TERM PERIOD.  
 
A SURFACE RIDGE AXIS STRETCHING FROM CENTRAL CANADA DOWN INTO THE  
LOWER MISSOURI RIVER VALLEY WILL BUILD IN THURSDAY NIGHT. MOSTLY  
CLEAR SKIES AND LIGHT WINDS SHOULD LEAD TO A WIDESPREAD FREEZE EARLY  
FRIDAY MORNING, WHICH WILL END THE GROWING SEASON.  
   
LONG TERM
 
(FRIDAY THROUGH WEDNESDAY)  
ISSUED AT 225 PM CDT WED OCT 20 2021  
 
THE SURFACE RIDGE WILL REMAIN NEARLY STATIONARY INTO SATURDAY,  
CONTINUING THE COOLER TREND. RAIN CHANCES WILL RETURN SUNDAY WITH A  
SYSTEM PASSING WELL TO THE SOUTH ACROSS MISSOURI. THE ACTIVE PATTERN  
WILL CONTINUE THROUGH NEXT WEEK AS SYSTEM AFTER SYSTEM CRASHES ONTO  
THE WEST COAST. A LONG WAVE TROUGH PASSING ACROSS THE ROCKIES WILL  
SPAWN LOW PRESSURE OVER THE WEST CENTRAL PLAINS TUESDAY NIGHT. THE  
TRACK OF THIS RESULTANT LOW HAS EXHIBITED CONSIDERABLE SPREAD OVER  
THE LAST 24 HOURS. YESTERDAY, MODELS HAD PHASED THE UPPER LOW WITH  
THE NORTHERN STREAM TROUGH, WHICH ALLOWED FOR A WELL-DEVELOPED  
SYNOPTIC SYSTEM TRACKING TO OUR NORTHWEST. THIS PLACED THE REGION IN  
THE WARM SECTOR WITH HIGHS IN THE 70S BY TUESDAY. NOW, THE SYSTEM IS  
MUCH LESS PHASED WITH THE UPPER LOW CUT OFF FROM THE NORTHERN  
STREAM. THE ECMWF TAKES THE SURFACE LOW EAST ACROSS THE MID SOUTH BY  
WEDNESDAY EVENING AND INTO GEORGIA THURSDAY. THIS IS IN STARK  
CONTRAST TO 24 HOURS AGO WHEN IT TOOK THE LOW NORTH ACROSS THE  
EASTERN PLAINS AND TO HUDSON BAY AS A 970 MB LOW. I HAVE NOT SEEN A  
SHIFT LIKE THAT IN QUITE SOME TIME. NEEDLESS TO SAY, CONFIDENCE WITH  
THAT SYSTEM IS VERY LOW AT THIS TIME.  
 

 
   
AVIATION
 
(FOR THE 06Z TAFS THROUGH 06Z THURSDAY NIGHT)  
ISSUED AT 1107 PM CDT WED OCT 20 2021  
 
NO SIGNIFICANT CHANGES FROM THE PREVIOUS DISCUSSION. EXPECT MVFR/IFR  
CONDITIONS TO CONTINUE OVERNIGHT AS A LOW PRESSURE SYSTEM BRINGS  
STRATUS AND PERIODS OF RAIN SHOWERS. WINDS WILL BE EASTERLY AHEAD OF  
THE LOW, AND THEN TURN NORTHWESTERLY BEHIND IT. GUIDANCE CONTINUES TO  
SHOW CLOUDS MOVING OUT RATHER QUICKLY THIS MORNING, SO SHOULD HAVE  
VFR CONDITIONS FOR MOST OF THURSDAY THROUGH THE END OF THE TAF  
PERIOD.  
 
KMSP...  
NO SIGNIFICANT CHANGES FROM THE PREVIOUS DISCUSSION. EXPECT MVFR/IFR  
CONDITIONS TO CONTINUE OVERNIGHT AS A LOW PRESSURE SYSTEM BRINGS  
STRATUS AND PERIODS OF RAIN SHOWERS. WINDS WILL BE EASTERLY AHEAD OF  
THE LOW, AND THEN TURN NORTHWESTERLY BEHIND IT.VFR CONDITIONS SHOULD  
RETURN BY MID-MORNING AS DRIER AIR MOVES ACROSS THE REGION.  
 
/OUTLOOK FOR KMSP/  
SAT...VFR. WIND E 5-10 KTS.  
SUN...CHC MVFR/SHRA. WIND E 10-15 KTS.  
MON...VFR WITH MVFR/-RA POSSIBLE EARLY. WIND E AT 10G20 KTS.  
 

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

 
 

 
 
SHORT TERM...BORGHOFF  
LONG TERM...BORGHOFF  
AVIATION...JRB  
 
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