647  
ACUS02 KWNS 190547  
SWODY2  
SPC AC 190546  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1246 AM CDT SAT SEP 19 2026  
 
VALID 201200Z - 211200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF  
CENTRAL INTO EASTERN OKLAHOMA AND THE COLORADO FRONT RANGE...  
   
..SUMMARY
 
 
A FEW SEVERE WIND AND HAIL PRODUCING THUNDERSTORMS ARE POSSIBLE OVER  
EASTERN COLORADO, WITH SEVERE GUSTS ALSO LIKELY TO ACCOMPANY STORMS  
OVER PORTIONS OF OKLAHOMA TOMORROW (SUNDAY). ISOLATED SEVERE  
THUNDERSTORMS ARE ALSO POSSIBLE FROM THE OZARK VALLEY TO THE CENTRAL  
APPALACHIANS.  
   
..SYNOPSIS
 
 
MULTIPLE MID-LEVEL IMPULSES WILL PIVOT AROUND A DE-AMPLIFYING UPPER  
RIDGE AND TRAVERSE THE CENTRAL CONUS TOMORROW (SUNDAY). THESE  
IMPULSES WILL ENCOURAGE THE GRADUAL SOUTHWARD PROGRESSION OF A  
SURFACE COLD FRONT, PRECEDED BY A SEASONABLY MOIST AND UNSTABLE  
BOUNDARY LAYER, TO SUPPORT THUNDERSTORM DEVELOPMENT ACROSS MUCH OF  
THE SOUTHERN PLAINS TO THE OH VALLEY. GIVEN STRONGER BUOYANCY IN  
PROXIMITY TO THE COLD FRONT, SEVERE THUNDERSTORMS ARE POSSIBLE,  
ESPECIALLY OVER THE SOUTHERN PLAINS. UPSLOPE FLOW ALONG THE WESTERN  
FLANK OF THE COLD FRONT INTO THE CENTRAL HIGH PLAINS WILL ENCOURAGE  
A SEVERE THREAT IN THIS REGION AS WELL.  
   
..SOUTHERN PLAINS
 
 
SOME CLOUD COVER, ALONG WITH WIDELY SCATTERED SHOWERS AND  
THUNDERSTORMS, MAY BE IN PLACE ACROSS PORTIONS OF THE SOUTHERN  
PLAINS INTO THE OZARKS BY SUNDAY MORNING. AS SUCH, THERE ARE SOME  
UNCERTAINTIES REGARDING HOW THESE INITIAL CONDITIONS WILL IMPACT  
DOWNSTREAM CONVECTIVE EVOLUTION. NONETHELESS, GUIDANCE CONSENSUS  
SUGGESTS THAT SURFACE TEMPERATURES WILL WARM AHEAD OF THE FRONT INTO  
THE 90S F, WITH 70 F DEWPOINTS, YIELDING 2500-3500 J/KG MLCAPE AMID  
WANING INHIBITION. THIS WILL SUPPORT THUNDERSTORM INITIATION BY MID  
TO LATE AFTERNOON. GIVEN MEDIOCRE VERTICAL SHEAR PROFILES, STORMS  
SHOULD QUICKLY MERGE AND BECOME OUTFLOW DOMINANT. HOWEVER, GIVEN THE  
POTENTIAL FOR STRONG BUOYANCY, A SHORT-LIVED COLD-POOL-DRIVEN MCS  
MAY DEVELOP, ACCOMPANIED BY A FOCUSED SEVERE GUST THREAT IN  
CENTRAL/EASTERN OK.  
   
..PORTIONS OF MO INTO THE OH VALLEY AND CENTRAL APPALACHIANS
 
 
ISOLATED TO WIDELY SCATTERED THUNDERSTORM DEVELOPMENT IS LIKELY ALL  
ALONG THE COLD FRONT AND PERIPHERY OF THE DECAYING UPPER RIDGE, FROM  
THE OZARKS TO THE CENTRAL APPALACHIANS, DURING THE AFTERNOON GIVEN  
BOUNDARY-LAYER DESTABILIZATION. THE CONVERGENCE OF UPPER 60S F  
DEWPOINTS ALONG THE FRONT WILL BOOST MLCAPE TO OVER 2000 J/KG. A FEW  
OF THE STRONGER MULTICELLULAR COMPLEXES MAY PRODUCE A COUPLE  
INSTANCES OF SEVERE WIND/HAIL, THOUGH THE SEVERE THREAT SHOULD BE  
LIMITED TO SOME DEGREE GIVEN MAINLY 6 C/KM MID-LEVEL LAPSE RATES AND  
MEDIOCRE VERTICAL WIND SHEAR.  
   
..PORTIONS OF EASTERN COLORADO
 
 
ALONG THE WESTERN FLANK OF THE COLD FRONT, UPSLOPE FLOW INTO EASTERN  
COLORADO DURING THE AFTERNOON, WILL ENCOURAGE SCATTERED THUNDERSTORM  
DEVELOPMENT. NOTABLE VEERING FLOW ABOVE THE BOUNDARY LAYER, ALONG  
WITH INCREASING WESTERLY FLOW THROUGH THE REMAINDER OF THE  
TROPOSPHERE, WILL RESULT IN ELONGATED HODOGRAPHS AND 40-50 KTS OF  
EFFECTIVE BULK SHEAR. A FEW OF THE STRONGER STORMS SHOULD BECOME  
SUPERCELLULAR. GIVEN 7-8 C/KM MID-LEVEL LAPSE RATES, SUPERCELLS MAY  
BE ACCOMPANIED BY BOTH SEVERE WIND AND HAIL.  
 
..SQUITIERI.. 09/19/2026  
 

 
 
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