773  
ACUS01 KWNS 120030  
SWODY1  
SPC AC 120028  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0728 PM CDT FRI SEP 11 2026  
 
VALID 120100Z - 121200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER FAR EASTERN  
SOUTH DAKOTA INTO PORTIONS OF MINNESOTA...  
   
..SUMMARY
 
 
WIDELY SCATTERED SEVERE THUNDERSTORMS CAPABLE OF PRODUCING LARGE  
HAIL UP TO TWO INCHES, DAMAGING WINDS, AND A COUPLE OF TORNADOES  
WILL CONTINUE THROUGH THE REMAINDER OF THE EVENING INTO TONIGHT FROM  
FAR EASTERN SOUTH DAKOTA INTO PORTIONS OF MINNESOTA. ISOLATED  
OCCURRENCES OF SEVERE WIND GUSTS AND LARGE HAIL REMAIN POSSIBLE OVER  
PARTS OF THE CENTRAL PLAINS TONIGHT.  
   
..UPPER MISSISSIPPI VALLEY INTO THE CENTRAL PLAINS
 
 
A BROKEN BAND OF THUNDERSTORMS HAS RECENTLY DEVELOPED FROM FAR  
EASTERN SD INTO NORTH-CENTRAL MN WITHIN A RELATIVELY NARROW  
INSTABILITY AXIS PRECEDING A SURFACE COLD FRONT AND DRYLINE. THE  
PRESENCE OF STEEP MID-LEVEL LAPSE RATES (PER 00Z ABR SOUNDING) ATOP  
BOUNDARY-LAYER DEWPOINTS IN THE MID TO UPPER 60S F IS RESULTING IN  
MLCAPE UP TO 1500-2000 J/KG. AS MENTIONED ABOVE, THE CORRIDOR OF  
STRONGER INSTABILITY AND MINIMAL CAPPING IS RATHER NARROW  
LONGITUDINALLY, WHICH SUGGESTS THE SEVERE WEATHER THREAT MAY REMAIN  
SOMEWHAT LIMITED SPATIALLY INTO TONIGHT.  
 
THE KFSD VWP IS LIKELY INDICATIVE OF THE AMBIENT KINEMATIC  
ENVIRONMENT, WHICH FEATURES 35-40 KT OF DEEP-LAYER SHEAR AND  
RELATIVELY STRONG LOW-LEVEL SHEAR, SUPPORTIVE OF A SUPERCELL STORM  
MODE WITH THE PRIMARY HAZARD BEING LARGE HAIL UP TO TWO INCHES.  
TORNADO POTENTIAL WILL BE CONDITIONAL ON THE MAINTENANCE OF  
SEMI-DISCRETE SUPERCELLS RESIDING WITHIN THE NARROW AXIS OF MINIMAL  
CONVECTIVE INHIBITION. DAMAGING WIND POTENTIAL MAY TEND TO INCREASE  
BY LATE EVENING AS THUNDERSTORMS EVOLVE INTO LINE SEGMENTS.  
 
ADDITIONAL STORMS APPEAR POSSIBLE LATE THIS EVENING INTO TONIGHT  
AHEAD OF A SOUTHEASTWARD-MOVING COLD FRONT OVER PORTIONS OF EASTERN  
AND CENTRAL NE. SIMILAR TO LOCATIONS TO THE NORTH, A RELATIVELY  
NARROW ZONE OF MINIMAL CONVECTIVE INHIBITION AND MODERATE  
INSTABILITY EXISTS AHEAD OF THE FRONT, WHICH LEADS TO UNCERTAINTY IN  
THE AREAL COVERAGE AND DURATION OF THE THREAT. SEVERE WIND GUSTS  
WILL BE THE PRIMARY HAZARD WITH ANY SURFACE-BASED STORMS THAT CAN  
BECOME ESTABLISHED, THOUGH ISOLATED OCCURRENCES OF LARGE HAIL ARE  
ALSO POSSIBLE.  
 
..MEAD.. 09/12/2026  
 

 
 
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