191  
ACUS02 KWNS 110457  
SWODY2  
SPC AC 110455  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1155 PM CDT SAT OCT 10 2026  
 
VALID 121200Z - 131200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST
 
 
   
..SUMMARY
 
 
NO SEVERE WEATHER IS EXPECTED MONDAY THROUGH MONDAY NIGHT.  
   
..SYNOPSIS
 
 
AN UPPER LOW INITIALLY OVER THE COLUMBIA BASIN WILL DEVELOP SOUTH TO  
THE SIERRA NEVADA, WHILE AN EMBEDDED VORTICITY MAXIMUM PROGRESSES  
THROUGH THE BASAL PORTION THAT FEATURE FROM CENTRAL/SOUTHERN CA  
THROUGH THE LOWER-CO VALLEY INTO THE GREAT BASIN. DOWNSTREAM FROM  
THOSE DEVELOPMENTS, A LOW-AMPLITUDE SHORT-WAVE TROUGH IS FORECAST TO  
TRANSLATE FROM THE NORTHERN OR CENTRAL HIGH PLAINS INTO THE UPPER  
MIDWEST AND NEIGHBORING UPPER GREAT LAKES REGIONS BY MONDAY NIGHT.  
AT THE SURFACE, AN AREA OF LOW PRESSURE INITIALLY OVER CENTRAL NE  
WILL DEVELOP ALONG A BOUNDARY INTO SOUTHERN MN BY LATE AFTERNOON OR  
EARLY EVENING BEFORE REACHING CENTRAL WI MONDAY NIGHT.  
 
   
..UPPER MIDWEST
 
 
A PLUME OF STEEP MIDLEVEL LAPSE RATES WILL OVERSPREAD THE REGION ON  
MONDAY, ATOP A MOISTENING BOUNDARY LAYER, YIELDING A MODERATELY  
UNSTABLE BUT CAPPED AIR MASS BY AFTERNOON ALONG AND SOUTH OF THE  
SURFACE BOUNDARY AND APPROACHING CYCLONE. ELEVATED THUNDERSTORMS ARE  
EXPECTED TO DEVELOP TO THE NORTH OF THE SURFACE WARM SECTOR OVER THE  
NORTHERN PLAINS MONDAY MORNING WITHIN A ZONE OF FORCING FOR ASCENT  
PRECEDING THE SHORT-WAVE TROUGH. THAT CONVECTIVE REGIME IS EXPECTED  
TO SPREAD INTO PORTIONS OF MN AND WI LATE MONDAY AFTERNOON INTO  
NIGHT, AMIDST A THERMODYNAMIC ENVIRONMENT FEATURING MUCAPE GENERALLY  
LESS THAN 1000 J/KG. WHILE A FEW INSTANCES OF HAIL APPROACHING ONE  
INCH APPEAR POSSIBLE, LARGER SIZES ARE EXPECTED TO BE LIMITED BY THE  
MARGINAL INSTABILITY AND GENERALLY LESS THAN 30-35 KT OF EFFECTIVE  
BULK SHEAR.  
 
   
..LOWER COLORADO VALLEY INTO THE GREAT BASIN
 
 
INCREASED FORCING FOR ASCENT AHEAD OF THE VORTICITY MAXIMUM IS  
EXPECTED TO FOSTER AN AREAL INCREASE IN LOW-TOPPED THUNDERSTORMS  
MONDAY AFTERNOON, WHICH ARE LIKELY TO CONTINUE INTO MONDAY NIGHT.  
GENERALLY WEAK INSTABILITY SHOULD LIMIT SEVERE WEATHER POTENTIAL;  
HOWEVER, IN AREAS WHERE LOW-LEVEL LAPSE RATES CAN SUFFICIENTLY  
STEEPEN, THE DOWNWARD TRANSFER OF STRONGER WINDS ALOFT COULD YIELD A  
FEW GUSTS APPROACHING 58 MPH. SOME SMALL HAIL MAY ALSO ACCOMPANY THE  
STRONGEST UPDRAFTS.  
 
..MEAD.. 10/11/2026  
 

 
 
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