122  
ACUS01 KWNS 210101  
SWODY1  
SPC AC 210100  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0800 PM CDT SUN SEP 20 2026  
 
VALID 210100Z - 211200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CENTRAL HIGH PLAINS....  
   
..SUMMARY  
 
THUNDERSTORMS WITH LARGE HAIL AND SEVERE WIND GUSTS WILL BE POSSIBLE  
THIS EVENING ACROSS PARTS OF THE CENTRAL HIGH PLAINS. A FEW SEVERE  
WIND GUSTS MAY ALSO OCCUR FROM THE OZARKS NORTHEASTWARD INTO THE  
OHIO VALLEY.  
   
..CENTRAL HIGH PLAINS  
 
THE LATEST WATER VAPOR IMAGERY SHOWS A SHORTWAVE MID-LEVEL TROUGH  
OVER EASTERN COLORADO. AN AXIS OF MODERATE INSTABILITY, WITH MLCAPE  
IN THE 1500 TO 2000 J/KG RANGE, IS ANALYZED BY THE RAP JUST AHEAD OF  
THIS FEATURE FROM NEAR THE COLORADO-KANSAS STATE LINE SOUTHEASTWARD  
INTO THE OKLAHOMA PANHANDLE. AN ISOLATED SUPERCELL IS CURRENTLY  
ONGOING NEAR THE INSTABILITY AXIS NEAR LAMAR, COLORADO. RAP FORECAST  
SOUNDINGS AHEAD OF THIS CELL ACROSS FAR SOUTHWEST KANSAS EARLY THIS  
EVENING HAVE MLCAPE IN THE 1500 TO 2000 J/KG RANGE, 0-6 KM SHEAR  
NEAR 40 KNOTS AND 700-500 MB LAPSE RATES AROUND 7 C/KM. THIS  
ENVIRONMENT WILL CONTINUE TO SUPPORT SUPERCELLS CAPABLE OF LARGE  
HAIL AND WIND DAMAGE. THE THREAT COULD PERSIST INTO THE MID TO LATE  
EVENING WITH PARTS OF SOUTHWEST KANSAS AND THE OKLAHOMA PANHANDLE  
BEING AFFECTED. LATER THIS EVENING, SHORT-TERM MODEL FORECASTS ALSO  
SUGGEST THAT REDEVELOPMENT MAY OCCUR TO THE EAST OF THE DENVER  
METRO, WITH A NEW CLUSTER POTENTIALLY TRACKING SOUTHEASTWARD NEAR  
THE INSTABILITY AXIS. THIS ACTIVITY COULD ALSO POSE A LARGE HAIL AND  
WIND DAMAGE THREAT.  
   
..OZARKS INTO THE OHIO VALLEY  
 
SEVERAL MINOR PERTURBATIONS, EMBEDDED IN WESTERLY FLOW ALOFT, APPEAR  
TO MOVING THROUGH A CORRIDOR FROM THE OZARKS EASTWARD INTO THE OHIO  
VALLEY. THE MOST PRONOUNCED FEATURE APPEARS TO BE LOCATED IN  
SOUTHEASTERN INDIANA, AHEAD OF WHICH A SMALL CLUSTER OF SEVERE  
STORMS IS ONGOING. ALONG THE PROJECTED TRACK OF THESE STORMS, THE  
RAP HAS MLCAPE IN THE 1200 TO 1500 J/KG RANGE WITH 0-6 KM AROUND 35  
KNOTS. THIS SHOULD CONTINUE TO SUPPORT AN ISOLATED WIND-DAMAGE  
THREAT FOR A COUPLE MORE HOURS EARLY THIS EVENING...SEE MCD 2319.  
 
FURTHER SOUTHWEST INTO THE PARTS OF THE OZARKS AND MID MISSISSIPPI  
VALLEY, MODERATE INSTABILITY IS ANALYZED BY THE RAP FROM FAR  
NORTHEAST OKLAHOMA NORTHEASTWARD INTO SOUTH-CENTRAL ILLINOIS.  
ISOLATED TO SCATTERED THUNDERSTORMS ARE ONGOING NEAR THE INSTABILITY  
AXIS. THESE STORMS MAY BE CAPABLE OF PRODUCING ISOLATED SEVERE WIND  
GUSTS FOR ANOTHER HOUR OR TWO THIS EVENING...SEE MCD 2318.  
 
..BROYLES.. 09/21/2026  
 
 
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