060  
ACUS01 KWNS 191631  
SWODY1  
SPC AC 191629  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1129 AM CDT SAT SEP 19 2026  
 
VALID 191630Z - 201200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CENTRAL PLAINS AND CENTRAL HIGH PLAINS...  
   
..SUMMARY
 
 
THUNDERSTORMS WITH SCATTERED SEVERE WIND GUSTS AND LARGE HAIL ARE  
POSSIBLE THIS AFTERNOON AND EVENING ACROSS PARTS OF THE CENTRAL  
PLAINS.  
   
..OHIO VALLEY
 
 
RECENT SURFACE ANALYSIS PLACES A WEAK LOW OVER NORTHERN IN, ALONG  
THE NORTHERN END OF AN OUTFLOW BOUNDARY THAT IS PUSHING  
SOUTHWARD/SOUTH-SOUTHEASTWARD ACROSS CENTRAL IL AND CENTRAL IN.  
AIRMASS SOUTH OF THIS BOUNDARY IS VERY MOIST, WITH DEWPOINTS  
GENERALLY IN THE UPPER 60S TO LOW 70S. FILTERED HEATING IS  
ANTICIPATED ACROSS THIS REGION TODAY, WITH THE RESULTING WARM AND  
MOIST CONDITIONS SUPPORTING MODERATE BUOYANCY. THE STRONGEST  
BUOYANCY IS EXPECTED FROM SOUTHERN IN INTO SOUTHWEST OH AND ADJACENT  
FAR NORTHERN KY. THE SURGING CHARACTER OF THE OUTFLOW COMBINED WITH  
LIMITED DEEP-LAYER VERTICAL SHEAR RESULTS IN UNCERTAINTY REGARDING  
HOW THUNDERSTORMS WILL EVOLVE THIS AFTERNOON, WITH AT LEAST SOME  
POTENTIAL FOR A PREDOMINANCE OF UNDERCUT, POORLY ORGANIZED UPDRAFTS.  
THAT BEING SAID, POTENTIAL ALSO EXISTS FOR JUST ENOUGH  
BUOYANCY/SHEAR BALANCE FOR A FEW STRONGER, MORE PERSISTENT BOWING  
CLUSTERS. STEEP LOW-LEVEL LAPSE RATES WILL PROMOTE STRONG TO SEVERE  
GUSTS WITH ANY MORE PERSISTENT LINE SEGMENTS THAT DEVELOP.  
   
..SOUTHERN APPALACHIANS/SOUTHEAST
 
 
WARM AND MOIST CONDITIONS WILL SUPPORT AIRMASS DESTABILIZATION AND  
THE POTENTIAL OF AFTERNOON/EVENING THUNDERSTORMS ACROSS THE REGION.  
THE REGION IS LARGELY VOID OF COHERENT SURFACE FEATURES, SO ANY  
CONVECTIVE INITIATION WOULD LIKELY BE TIED TO MESOSCALE AREAS OF  
LOW-LEVEL CONFLUENCE. WIDELY SCATTERED TO SCATTERED STORMS ARE  
FORECAST DURING THE AFTERNOON, AND A FEW STRONGER WATER-LOADED  
DOWNDRAFTS CAPABLE OF 50 TO 60 MPH GUSTS ARE POSSIBLE.  
   
..CENTRAL AND SOUTHERN PLAINS/LOWER MISSOURI VALLEY
 
 
RECENT SURFACE ANALYSIS PLACES A LOW OVER SOUTHWEST IA, WITH A COLD  
FRONT EXTENDING BACK SOUTHWESTWARD THROUGH SOUTHWEST KS AND THE  
CENTRAL OK PANHANDLE INTO THE NORTHWEST TX PANHANDLE. THIS FRONT IS  
EXPECTED TO SLOWLY PUSH SOUTH WHILE LARGER-SCALE MID-LEVEL TROUGHING  
OVER THE GREAT BASIN AND CENTRAL ROCKIES GRADUALLY SHIFTS EASTWARD.  
A SEASONABLY MOIST AIRMASS IS IN PLACE AHEAD OF THE COLD FRONT, AND  
MODERATE BUOYANCY IS EXPECTED AS THIS AIRMASS HEATS AND DESTABILIZES  
THIS AFTERNOON.  
 
LOW-LEVEL CONVERGENCE ALONG THE COLD FRONT, AUGMENTED BY MODEST  
LARGE-SCALE FORCING FOR ASCENT, WILL SUPPORT SCATTERED STORM  
DEVELOPMENT DURING THE LATE AFTERNOON AND EARLY EVENING AS  
CONVECTIVE INHIBITION IS LOCALLY ERODED. GIVEN ADEQUATE SPEED AND  
DIRECTIONAL SHEAR, A FEW SHORT-LIVED SUPERCELLS ARE POSSIBLE EARLY  
IN THE CONVECTIVE CYCLE, PARTICULARLY ACROSS KS. LARGE HAIL WILL BE  
POSSIBLE WITH THE STRONGER UPDRAFTS. THEREAFTER, HIGH-BASED STORM  
CHARACTER COUPLED WITH STEEP LOW-LEVEL LAPSE RATES WILL SUPPORT  
STRONG TO SEVERE GUSTS, INCLUDING THE POTENTIAL FOR A FEW GUSTS OF  
60 TO 75 MPH.  
   
..CENTRAL HIGH PLAINS
 
 
LOW-LEVEL EASTERLY FLOW ACROSS THE CENTRAL HIGH PLAINS WILL HELP  
MAINTAIN AT LEAST UPPER 50S/LOW 60S DEWPOINTS ACROSS THE REGION THIS  
AFTERNOON/EVENING. THE LOW-AMPLITUDE SHORTWAVE TROUGH CURRENTLY  
MOVING THROUGH NORTHERN NV/UT IS FORECAST TO CONTINUE EASTWARD,  
INTERACTING WITH THIS MOIST AND UNSTABLE AIRMASS TO SUPPORT  
SCATTERED THUNDERSTORM DEVELOPMENT. WITH TIME, STRENGTHENING  
MID-LEVEL FLOW WILL HELP SUPPORT UPSCALE GROWTH FROM A LOOSELY  
ORGANIZED BAND OF A STORMS (INCLUDING SOME SUPERCELLS) TO A MORE  
ORGANIZED LINEAR CLUSTER. SOME HAIL IS POSSIBLE EARLY WITH THE MORE  
CELLULAR DEVELOPMENT, WITH WIND GUSTS BECOMING MORE LIKELY WITH  
TIME. THERE IS SOME INDICATION THIS ACTIVITY MAY CONTINUE INTO  
WESTERN KS DURING THE LATE EVENING AND EARLY OVERNIGHT.  
 
..MOSIER/CHALMERS.. 09/19/2026  
 

 
 
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