925  
ACUS11 KWNS 211715  
SWOMCD  
SPC MCD 211715  
KYZ000-INZ000-TNZ000-ILZ000-MOZ000-ARZ000-211845-  
 
MESOSCALE DISCUSSION 1689  
NWS STORM PREDICTION CENTER NORMAN OK  
1215 PM CDT TUE JUL 21 2026  
 
AREAS AFFECTED...PORTIONS OF THE LOWER AND MIDDLE OHIO RIVER VALLEY  
 
CONCERNING...SEVERE POTENTIAL...WATCH LIKELY  
 
VALID 211715Z - 211845Z  
 
PROBABILITY OF WATCH ISSUANCE...80 PERCENT  
 
SUMMARY...NUMEROUS STRONG TO SEVERE THUNDERSTORMS ARE EXPECTED TO  
FORM ALONG A COLD FRONT THIS AFTERNOON BEFORE PROGRESSING  
SOUTHEASTWARD. DAMAGING TO SEVERE WIND GUSTS WILL BE THE PRIMARY  
THREAT, WITH BRIEF TORNADOES AND ISOLATED LARGE HAIL ALSO POSSIBLE.  
 
DISCUSSION...LATEST SURFACE ANALYSIS PLACES A COLD FRONT EXTENDING  
SOUTHWESTWARD FROM SOUTHERN LOWER MICHIGAN INTO CENTRAL INDIANA,  
SOUTHERN ILLINOIS, AND SOUTH-CENTRAL MISSOURI. A DEEPENING CUMULUS  
FIELD IS NOTED ALONG AND AHEAD OF THIS COLD FRONT, WITH TEMPERATURES  
APPROACHING THE LOW-90S F AND DEWPOINTS NEAR 80. OBSERVATIONAL  
TRENDS AND LATEST HIGH-RES GUIDANCE SUGGEST THAT ROBUST CONVECTIVE  
INITIATION WILL OCCUR ACROSS THIS REGION OVER THE NEXT 1-2 HOURS.  
STRONG MID-LEVEL FLOW OVERSPREADING THE REGION (~40 KTS SAMPLED  
AROUND 3 KM AGL BY THE LVX/VWX VAD PROFILES) AND STRONG EFFECTIVE  
SHEAR OF 50+ KTS WILL SUPPORT INITIAL SUPERCELLS, BUT LINEAR FORCING  
ALONG THE FRONT, WIDESPREAD INITIATION, AND COLD POOL CONGLOMERATION  
WILL PROMOTE RAPID UPSCALE GROWTH INTO ONE OR MORE LINEAR  
SEGMENTS/CLUSTERS. DAMAGING/SEVERE WIND GUSTS TO AROUND 70 MPH ARE  
EXPECTED TO BE THE MOST COMMON HAZARD, BUT BRIEF TORNADOES AND LARGE  
HAIL TO AROUND GOLF BALL SIZE ARE ALSO POSSIBLE.  
 
CONFIDENCE IS HIGHER IN GREATER STORM COVERAGE OCCURRING FROM  
SOUTHERN INDIANA INTO NORTHERN KENTUCKY, WITH MORE UNCERTAINTY  
SURROUNDING COVERAGE EXISTING FARTHER WEST (WHERE EFFECTIVE SHEAR IS  
ALSO FORECAST TO BE MODESTLY WEAKER). GIVEN THE EXPECTED SEVERE  
RISK, WATCH ISSUANCE IS LIKELY FOR AT LEAST A PORTION OF THE  
DISCUSSION AREA EARLY THIS AFTERNOON.  
 
..CHALMERS/MOSIER.. 07/21/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...LMK...OHX...IND...PAH...ILX...MEG...  
 
LAT...LON 36608692 36168805 35948908 35938997 36029029 36189042  
36539042 37049025 37638953 38468788 38698738 38918669  
39008617 39008586 38908553 38628524 38308505 37958492  
37568500 37228527 36968589 36608692  
 
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH  
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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