029  
ACUS11 KWNS 270035  
SWOMCD  
SPC MCD 270035  
AZZ000-270230-  
 
MESOSCALE DISCUSSION 2134  
NWS STORM PREDICTION CENTER NORMAN OK  
0735 PM CDT FRI SEP 26 2025  
 
AREAS AFFECTED...SOUTH-CENTRAL ARIZONA  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 621...  
 
VALID 270035Z - 270230Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 621  
CONTINUES.  
 
SUMMARY...ISOLATED STRONG TO SEVERE THUNDERSTORMS WILL REMAIN  
POSSIBLE FOR THE NEXT COUPLE OF HOURS, BUT THE OVERALL SEVERE THREAT  
IS BEGINNING TO WANE ACROSS SOUTH-CENTRAL ARIZONA.  
 
DISCUSSION...OVER THE PAST 30-45 MINUTES, CONVECTION ACROSS  
SOUTH-CENTRAL AZ HAS UNDERGONE STEADY WEAKENING PER MRMS METRICS AND  
CLOUD-TOP TEMPERATURES. THE EXCEPTION TO THIS IS A CLUSTER ACROSS  
PORTIONS OF NORTHEASTERN PINAL COUNTY WHERE RE-DEVELOPMENT ALONG A  
SOUTHWARD PROPAGATING OUTFLOW BOUNDARY CONTINUES TO PERIODICALLY  
INTENSIFY TO SEVERE LIMITS PER MRMS MESH AND KIWA VELOCITY DATA. A  
RECENT 00Z SOUNDING FROM TUS SAMPLED MODEST MID-LEVEL LAPSE RATES,  
BUT ADEQUATE LOW/MID-LEVEL MOISTURE TO SUPPORT AROUND 1000 J/KG  
MLCAPE WHEN ADJUSTED FOR WARMER SURFACE TEMPERATURES FURTHER NORTH  
NEAR THE ONGOING CLUSTER. DESPITE ADEQUATE BUOYANCY FOR DEEP  
CONVECTION, SURFACE OBSERVATIONS SHOW A SPATIALLY LIMITED WARM  
SECTOR REMAINS IN PLACE, LARGELY OVER PORTIONS OF EASTERN PINAL AND  
FAR EASTERN PIMA COUNTIES. WITH REDEVELOPMENT ALONG THE OUTFLOW  
BOUNDARY BECOMING INCREASINGLY SPARSE AND SEVERAL FAILED ATTEMPTS AT  
DEEP CONVECTION NOTED ALONG A WEAK SURFACE TROUGH OVER EASTERN PIMA  
COUNTY, STRONG/SEVERE THUNDERSTORM POTENTIAL APPEARS TO BE WANING.  
THIS TREND SHOULD CONTINUE HEADING INTO THE EVENING HOURS AS  
NOCTURNAL COOLING BEGINS TO INCREASE INHIBITION. NONETHELESS, SOME  
LOCALIZED SEVERE HAIL/WIND THREAT MAY LINGER ACROSS PORTIONS OF  
SOUTH-CENTRAL AZ FOR THE NEAR TERM GIVEN RESIDUAL BUOYANCY AND  
ADEQUATE DEEP-LAYER SHEAR.  
 
..MOORE.. 09/27/2025  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...TWC...FGZ...PSR...  
 
LAT...LON 31981156 32181165 33091163 33341154 33531133 33641103  
33641067 33401043 33211035 32291038 32101052 32041072  
31911132 31901146 31981156  
 
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
CLICK HERE TO GO TO PREVIOUS BULLETINS.
The Nexlab SPC Page
Main Text Page