923  
ACUS01 KWNS 201956  
SWODY1  
SPC AC 201955  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0255 PM CDT TUE OCT 20 2026  
 
VALID 202000Z - 211200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
ORGANIZED SEVERE THUNDERSTORMS ARE NOT EXPECTED THROUGH TONIGHT.  
   
..20Z UPDATE  
 
ISOLATED THUNDERSTORM DEVELOPMENT IS ONGOING ACROSS PORTIONS OF  
SOUTHEASTERN AZ AND SOUTHWESTERN NM WHERE LATEST OBJECTIVE ANALYSIS  
SUGGESTS MLCAPE HAS INCREASED TO AROUND 500 J/KG AMID DIURNAL  
HEATING AND MID-50S F SURFACE DEWPOINTS. WHILE TRANSIENT STORM  
ORGANIZATION AND A LOW-PROBABILITY RISK FOR MARGINALLY SEVERE HAIL  
AND/OR LOCALLY STRONG GUSTS REMAIN POSSIBLE, THE EXISTING OUTLOOK  
HAS BEEN MAINTAINED OWING TO THE EXPECTATION FOR ANY SEVERE RISK TO  
REMAIN LIMITED IN MAGNITUDE AND COVERAGE. SEE THE DISCUSSION BELOW  
FOR ADDITIONAL INFORMATION.  
 
..CHALMERS.. 10/20/2026  
   
PREV DISCUSSION  
/ISSUED 1125 AM CDT TUE OCT 20 2026/  
   
..SOUTHWEST  
 
BENEATH A BELT OF 30-40-KT SOUTHWESTERLY FLOW ALOFT, ISOLATED TO  
WIDELY SCATTERED THUNDERSTORM DEVELOPMENT IS EXPECTED ALONG THE  
HIGHER TERRAIN ACROSS PARTS OF SOUTHEASTERN AZ INTO WESTERN NM THIS  
AFTERNOON. DIURNAL HEATING AMID MIDDLE/UPPER 50S DEWPOINTS WILL  
YIELD WEAK SURFACE-BASED BUOYANCY, WHICH COMBINED WITH AROUND 35 KT  
OF EFFECTIVE SHEAR, MAY PROMOTE TRANSIENT STORM ORGANIZATION. WHILE  
AN ISOLATED INSTANCE OF MARGINALLY SEVERE HAIL (AROUND 1 INCH IN  
DIAMETER) AND/OR LOCALLY STRONG GUSTS CANNOT BE RULED OUT, THE  
OVERALL SEVERE THREAT IS EXPECTED TO REMAIN ISOLATED/LIMITED TODAY.  
 
AN INCREASE IN THUNDERSTORM COVERAGE IS EXPECTED LATE IN THE PERIOD  
ACROSS CENTRAL/NORTHERN AZ AS FORCING FOR ASCENT STRENGTHENS WITHIN  
THE EXIT REGION OF A ROBUST MIDLEVEL JET. WHILE DEEP-LAYER SHEAR  
WILL BE INCREASING, MOST OF THIS ACTIVITY SHOULD REMAIN ELEVATED  
AMID WEAK BUOYANCY -- LIMITING THE OVERALL SEVERE RISK.  
 
 
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