143  
ACUS11 KWNS 121642  
SWOMCD  
SPC MCD 121642  
OHZ000-KYZ000-INZ000-ILZ000-MOZ000-121915-  
 
MESOSCALE DISCUSSION 1655  
NWS STORM PREDICTION CENTER NORMAN OK  
1142 AM CDT SAT JUL 12 2025  
 
AREAS AFFECTED...IN...WESTERN/CENTRAL OH...NORTHERN/WESTERN  
KY...SOUTHERN IL...SOUTHEAST MO  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 121642Z - 121915Z  
 
PROBABILITY OF WATCH ISSUANCE...40 PERCENT  
 
SUMMARY...STORMS CAPABLE OF ISOLATED TO SCATTERED DAMAGING WINDS ARE  
POSSIBLE THIS AFTERNOON.  
 
DISCUSSION...A DIFFUSE COLD FRONT IS CURRENTLY MOVING ACROSS PARTS  
OF IL/IN, WITH EVIDENCE OF A GRAVITY WAVE PRECEDING THE FRONT FROM  
NORTHWEST OH INTO EAST/CENTRAL IN. CUMULUS IS GRADUALLY BUILDING IN  
THE VICINITY OF THIS PREFRONTAL FEATURE, WITH RECENT STORM  
INITIATION NOTED ACROSS FAR NORTHWEST OH. WITH WEAK MIDLEVEL LAPSE  
RATES IN PLACE, INITIAL CONVECTION MAY ONLY GRADUALLY INTENSIFY.  
HOWEVER, RICH MOISTURE AND MLCAPE INCREASING INTO THE 1500-2500 J/KG  
RANGE COULD EVENTUALLY SUPPORT MORE ROBUST STORM DEVELOPMENT  
ALONG/AHEAD OF THE COLD FRONT THIS AFTERNOON. DEEP-LAYER SHEAR IS  
GENERALLY WEAK, BUT STEEPENING LOW-LEVEL LAPSE RATES AND 20-30 KT OF  
SOUTHWESTERLY FLOW IN THE 850-700 MB LAYER MAY ALLOW FOR A FEW  
STRONGER OUTFLOW-DRIVEN CLUSTERS CAPABLE OF ISOLATED TO SCATTERED  
DAMAGING WIND.  
 
FARTHER SOUTHWEST, A WEAK STORM CLUSTER IS ONGOING FROM SOUTHEAST MO  
INTO SOUTHERN IL. HEATING/DESTABILIZATION AHEAD OF THIS CLUSTER MAY  
ALLOW FOR SOME INTENSIFICATION WITH TIME, ACCOMPANIED BY A THREAT  
FOR AT LEAST ISOLATED DAMAGING WINDS AS IT MOVES GENERALLY  
EAST-NORTHEASTWARD. ADDITIONAL STRONG STORMS MAY DEVELOP IN THE WAKE  
OF THIS CLUSTER LATER THIS AFTERNOON, ALONG THE DIFFUSE COLD FRONT  
AND ANY REMNANT OUTFLOW BOUNDARIES.  
 
COVERAGE OF THE ORGANIZED SEVERE THREAT ACROSS THE REGION REMAINS  
UNCERTAIN, BUT WATCH ISSUANCE IS POSSIBLE IF A CORRIDOR OF SOMEWHAT  
GREATER DAMAGING-WIND POTENTIAL BECOMES APPARENT.  
 
..DEAN/MOSIER.. 07/12/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...CLE...ILN...LMK...IWX...IND...PAH...ILX...LSX...  
 
LAT...LON 38048998 39468779 40478619 41658502 41718318 41348203  
39998306 38628486 37958616 37208804 36768958 37028995  
38048998  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
 
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