665  
ACUS01 KWNS 091942  
SWODY1  
SPC AC 091940  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0240 PM CDT TUE SEP 09 2025  
 
VALID 092000Z - 101200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
EASTERN COLORADO...WESTERN KANSAS...AND THE OKLAHOMA/TEXAS  
PANHANDLES...  
   
..SUMMARY
 
 
WIDELY SCATTERED SEVERE STORMS ARE POSSIBLE OVER THE CENTRAL AND  
SOUTHERN HIGH PLAINS LATE THIS AFTERNOON AND EVENING.  
   
..20Z UPDATE - CENTRAL/SOUTHERN HIGH PLAINS
 
 
THE SLIGHT RISK (LEVEL 2 OF 5) HAS BEEN EXPANDED SOUTHWARD TO  
INCLUDE SOUTHWEST KS AND PORTIONS OF THE OK/TX PANHANDLES. THIS  
CHANGE IS BASED ON LATEST MODIFIED RAP/NAM/HRRR/RRFS FORECAST  
SOUNDINGS, CAMS TRENDS, AS WELL AS OBSERVATION TRENDS.  
 
TEMPERATURES HAVE WARMED INTO THE UPPER 80S TO LOW 90S F ACROSS THE  
REGION, NEARING CONVECTIVE TEMPERATURES. VISIBLE SATELLITE IMAGERY  
SHOWS CUMULUS DEVELOPING IN SOUTHEAST CO WITHIN MODEST LOW-LEVEL  
UPSLOPE FLOW, WITH MINOR CONVERGENCE ALONG THE THETA-E GRADIENT AND  
SURFACE TROUGH FROM THE NORTHEAST TX PANHANDLE TOWARD THE CO/KS  
BORDER. ISOLATED TO WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO  
DEVELOP BY LATE AFTERNOON AND SPREAD EAST/SOUTHEAST INTO THIS  
EVENING.  
 
VERTICALLY VEERING WIND PROFILES, WITH FORECAST HODOGRAPHS BECOMING  
ELONGATED/STRAIGHT ABOVE 1-2 KM, WILL SUPPORT SUPERCELLS. STEEP LOW  
AND MIDLEVEL LAPSE RATES AND 1000-2500 J/KG MLCAPE VALUES AMID  
FAVORABLE SHEAR WILL FAVOR LARGE HAIL, WITH SOME POTENTIAL FOR  
STONES GREATER THAN 2 INCH DIAMETER POSSIBLE. STRONG GUSTS MAY ALSO  
ACCOMPANY STRONGER CONVECTION.  
 
..LEITMAN.. 09/09/2025  
   
PREV DISCUSSION
 
/ISSUED 1121 AM CDT TUE SEP 09 2025/  
   
..CENTRAL AND SOUTHERN HIGH PLAINS
 
 
THE UPPER RIDGE AXIS WILL REMAIN OVER THE ROCKIES TODAY, WITH  
NORTHWEST FLOW ALOFT ACROSS THE PLAINS STATES. HIGH-BASED  
THUNDERSTORMS ARE EXPECTED TO DEVELOP OFF THE HIGH TERRAIN OF  
CENTRAL CO AND NORTHERN NM BY MID-AFTERNOON, WHILE ISOLATED CELLS  
FORM OVER A REMNANT BOUNDARY OVER EASTERN CO/WESTERN KS. BACKED  
LOW-LEVEL WINDS, STEEP LOW AND MID-LEVEL LAPSE RATES, AND CAPE  
VALUES RANGING FROM 1000-2500 J/KG WILL PROMOTE A RISK OF A FEW  
SEVERE STORMS THROUGH THE AFTERNOON. LARGE HAIL APPEARS TO BE THE  
MAIN CONCERN, WITH GUSTY/DAMAGING WINDS ALSO POSSIBLE IN THE  
STRONGEST CELLS. ACTIVITY MAY PERSIST THROUGH MUCH OF THE EVENING  
AS IT PROGRESSES EASTWARD INTO AN INCREASINGLY MOIST BOUNDARY LAYER  
AIR MASS. 12Z CAMS SHOW A CONSISTENT SIGNAL OF MULTIPLE ROUNDS OF  
STORMS AFFECTING PARTS OF EASTERN CO/WESTERN KS, SO HAVE ADDED A  
SMALL SLGT RISK FOR THIS REGION.  
 

 
 
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