666  
ACUS11 KWNS 220721  
SWOMCD  
SPC MCD 220721  
AZZ000-220915-  
 
MESOSCALE DISCUSSION 2395  
NWS STORM PREDICTION CENTER NORMAN OK  
0221 AM CDT THU OCT 22 2026  
 
AREAS AFFECTED...PARTS OF CENTRAL ARIZONA  
 
CONCERNING...SEVERE THUNDERSTORM WATCH 690...  
 
VALID 220721Z - 220915Z  
 
THE SEVERE WEATHER THREAT FOR SEVERE THUNDERSTORM WATCH 690  
CONTINUES.  
 
SUMMARY...SCATTERED STRONG THUNDERSTORM DEVELOPMENT REMAINS POSSIBLE  
OVERNIGHT. ALTHOUGH THE POTENTIAL FOR SEVERE WEATHER MAY CURRENTLY  
BE AT A RELATIVE MINIMUM, IT APPEARS THAT THIS MAY INCREASE AGAIN BY  
4-6 AM MST. A NEW SEVERE WEATHER WATCH MAY BE NEEDED, BUT IT IS NOT  
CERTAIN WHETHER THIS WILL BE BEFORE WW 690 EXPIRES AT 09Z, OR A BIT  
LATER TONIGHT.  
 
DISCUSSION...THERE HAS BEEN LITTLE CHANGE IN THE LARGE-SCALE  
ENVIRONMENT THROUGH THE EVENING INTO THE OVERNIGHT HOURS, DOWNSTREAM  
OF A NOTABLE MID-LEVEL TROUGH AND EMBEDDED LOW SLOWLY MIGRATING  
INLAND OF THE SOUTHERN CALIFORNIA COAST. SOUTHERLY LOW-LEVEL FLOW  
IS MAINTAINING A SEASONABLY MOIST BOUNDARY-LAYER ACROSS THE LOWER  
DESERTS INTO MOGOLLON RIM VICINITY, WHICH HAS BEEN SUFFICIENT TO  
CONTRIBUTE TO CAPE ON THE ORDER OF 500-1000+ J/KG BENEATH MODESTLY  
COOL MID-LEVEL AIR. BENEATH STRONG SOUTH TO SOUTHWESTERLY FLOW IN  
THE 500-300 MB LAYER, DEEP-LAYER SHEAR REMAINS CONDUCIVE TO  
SUPERCELL DEVELOPMENT.  
 
FORCING FOR ASCENT NEAR AND NORTH OF THE GREATER PHOENIX AREA  
CONTINUES TO SUPPORT RENEWED THUNDERSTORM INITIATION, LARGELY AIDED  
BY LOW-LEVEL WARM ADVECTION AND UPSLOPE FLOW INTO AND ACROSS THE  
MOGOLLON RIM INTO COLORADO PLATEAU. THIS IS LIKELY TO CONTINUE  
THROUGH THE REMAINDER OF THE NIGHT.  
 
WITH THE CONTINUED APPROACH OF THE UPSTREAM TROUGH AXIS AND MORE  
SUBSTANTIVE MID-LEVEL HEIGHT FALLS, ALONG WITH PERHAPS SOME FURTHER  
STRENGTHENING OF LOW-LEVEL FLOW/SHEAR, LATEST MODEL OUTPUT  
(INCLUDING CONVECTION-ALLOWING AND RELATED MACHINE LEARNING  
GUIDANCE) SUGGESTS THAT THE ENVIRONMENT MAY ONCE AGAIN BECOME  
INCREASINGLY CONDUCIVE TO SUPERCELLS WITH POTENTIAL TO PRODUCE A  
TORNADO OR TWO, IN ADDITION TO LARGE HAIL, BY 11-13Z, IF NOT  
EARLIER.  
 
..KERR.. 10/22/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
 
 
ATTN...WFO...FGZ...PSR...  
 
LAT...LON 35361229 34911088 34031052 33191132 33351201 34431249  
35361229  
 
MOST PROBABLE PEAK TORNADO INTENSITY...85-110 MPH  
MOST PROBABLE PEAK WIND GUST...55-70 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
 
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