895  
ACUS11 KWNS 140404  
SWOMCD  
SPC MCD 140403  
OHZ000-KYZ000-INZ000-ILZ000-IAZ000-140600-  
 
MESOSCALE DISCUSSION 1974  
NWS STORM PREDICTION CENTER NORMAN OK  
1103 PM CDT THU AUG 13 2026  
 
AREAS AFFECTED...EASTERN IOWA...NORTHERN/CENTRAL ILLINOIS...AND  
CENTRAL INDIANA  
 
CONCERNING...SEVERE POTENTIAL...WATCH POSSIBLE  
 
VALID 140403Z - 140600Z  
 
PROBABILITY OF WATCH ISSUANCE...40 PERCENT  
 
SUMMARY...OCCASIONAL STRONGER STORMS MAY PRODUCE SMALL HAIL AND  
GUSTY WINDS OVERNIGHT.  
 
DISCUSSION...THUNDERSTORM ACTIVITY IS INCREASING WITHIN THE WARM  
ADVECTION REGIME ACROSS PORTIONS OF EASTERN IOWA INTO NORTHERN  
ILLINOIS/INDIANA. THIS ACTIVITY IS ONGOING NORTH OF A SURFACE FRONT  
EXTENDING FROM THE CENTRAL PLAINS ACROSS SOUTHERN ILLINOIS INTO  
SOUTHERN ILLINOIS/NORTHERN KENTUCKY. THE AIR MASS NEAR THE ONGOING  
CONVECTION IS ONLY MARGINALLY UNSTABLE LOCATED ON THE NORTHERN  
FRINGES OF MORE MODERATE TO STRONG INSTABILITY FURTHER SOUTH ACROSS  
SOUTHERN ILLINOIS INTO PORTIONS OF SOUTHERN INDIANA/NORTHERN  
KENTUCKY. FORECAST SOUNDINGS SUGGEST THE PRESENCE OF A FAIRLY STRONG  
CAP AT THE BASE OF THE EML ACROSS MUCH OF THE REGION OF GREATER  
BUOYANCY, WHICH WILL LIKELY INHIBIT SURFACE BASED CONVECTION.  
 
GENERALLY BOUNDARY PARALLEL FLOW WILL LIKELY PRODUCE TRAINING STORMS  
OVERNIGHT, WITH LITTLE ORGANIZED SEVERE POTENTIAL. LATER INTO THE  
OVERNIGHT/EARLY MORNING, THE LOW-LEVEL JET WILL INCREASE INTO  
ILLINOIS/INDIANA. SHOULD A CLUSTER BE ABLE TO DEVELOP AND DROP  
SOUTHWARD, THERE COULD BE SOME DAMAGING WIND POTENTIAL INTO THE  
MORNING. A FEW INSTANCES OF GUSTY WINDS AND SMALL HAIL WILL BE  
POSSIBLE WITH STRONGER CORES. FOR NOW, CONFIDENCE IN A MORE  
ORGANIZED SEVERE RISK REMAINS LOW BUT TRENDS WILL BE MONITORED  
OVERNIGHT.  
 
..THORNTON/HART.. 08/14/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...ILN...LMK...IWX...IND...LOT...ILX...LSX...DVN...  
 
LAT...LON 41788993 41859141 41379201 40489155 40219102 39588904  
38778560 38678459 39108416 39748424 40288456 41248686  
41638908 41788993  
 
MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH  
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page