775  
ACUS01 KWNS 221642  
SWODY1  
SPC AC 221641  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1141 AM CDT THU OCT 22 2026  
 
VALID 221630Z - 231200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS  
ARIZONA/WESTERN NEW MEXICO AND FOUR CORNERS...  
   
..SUMMARY  
 
SCATTERED SEVERE THUNDERSTORMS ARE EXPECTED ACROSS THE SOUTHWEST,  
WITH THE MOST INTENSE CELLS EXPECTED ACROSS PARTS OF ARIZONA AND  
WESTERN NEW MEXICO THIS AFTERNOON AND EVENING. LARGE HAIL, DAMAGING  
WINDS, AND A FEW TORNADOES ARE ALL POSSIBLE.  
   
..ARIZONA/FOUR CORNERS AND GREAT BASIN  
 
ANOTHER ACTIVE AND RELATIVELY RARE SETUP FROM A CLIMATOLOGICAL  
PERSPECTIVE CONTINUES REGIONALLY, AND WILL TEND TO SHIFT  
EAST-NORTHEASTWARD THROUGH THE AFTERNOON AND EVENING. THIS WILL BE  
AS THE UPPER LOW IN VICINITY OF THE SOCAL COAST CONTINUES TO BECOME  
MORE NORTHEASTWARD PROGRESSIVE TODAY, REACHING PORTIONS OF THE GREAT  
BASIN AND LOWER COLORADO RIVER VALLEY BY THIS EVENING.  
 
SCENARIO WILL CONTINUE TO FAVOR SUPERCELLS, PARTICULARLY FOR EASTERN  
ARIZONA AND WESTERN NEW MEXICO FROM A LONGER-DURATION AND TORNADO  
PERSPECTIVE, AS LOW-LEVEL WINDS OTHERWISE WILL TEND TO TAKE ON MORE  
OF A WESTERLY COMPONENT OVER TIME FARTHER WEST ACROSS ARIZONA AS THE  
UPPER TROUGH APPROACHES. SEVERE PROBABILITIES HAVE BEEN  
INCREASED/EXPANDED NORTHWARD TOWARD THE FOUR CORNERS/COLORADO  
PLATEAU VICINITY, WHERE AN ATYPICALLY RARE SETUP OF  
DEEP-LAYER/LOW-LEVEL SHEAR COINCIDENT WITH MODEST BUT ADEQUATE  
SEVERE-CONDUCIVE DEGREE OF DESTABILIZATION IS EXPECTED.  
 
AS COMPARED TO YESTERDAY, A GREATER COVERAGE OF STORMS WILL LIKELY  
EXIST BY LATER TODAY/AFTERNOON, WHICH MAY MEAN A LESS-DISCRETE  
NATURE OF THE SUPERCELLS, BUT WITH MORE NUMEROUS  
SEVERE-CALIBER/SUPERCELL STORMS CAPABLE OF LARGE HAIL, DAMAGING  
WINDS AND A TORNADO RISK. RECENT TUCSON WSR-88D VWP DATA STILL  
REFLECTS STRONG LOW-LEVEL SHEAR/SRH AND (SPLITTING)  
SUPERCELL-FAVORABLE DEEP-LAYER WIND PROFILES, WITH THE PROBABILITY  
THAT TORNADO POTENTIAL WILL PROBABLY MAXIMIZE ACROSS EASTERN  
ARIZONA/FAR WESTERN NEW MEXICO THIS AFTERNOON INTO EVENING,  
ESPECIALLY WHERE TOPOGRAPHY INFLUENCES A LOW-LEVEL EASTERLY WIND  
COMPONENT. LARGE HAIL WILL BE ASSOCIATED WITH BOTH LEFT-MOVING AND  
RIGHT-MOVING SUPERCELLS.  
 
FARTHER NORTH-NORTHWEST INTO THE GREAT BASIN, BOTH LOW-LEVEL  
MOISTURE AND RELATED MLCAPE ARE GENERALLY MORE LIMITED. EVEN SO,  
MULTIPLE CORRIDORS OF ISOLATED SEVERE HAIL/WIND AND BRIEF TORNADO  
POTENTIAL WILL EXIST THIS AFTERNOON. THIS WILL BE AS SEMI-LOW-TOPPED  
CONVECTION DEVELOPS AHEAD OF THE EASTWARD-TRANSLATING UPPER  
TROUGH/LOW AMID STRONG SOUTHERLY FLOW/SHEAR THROUGH MUCH OF THE  
TROPOSPHERE.  
 
..GUYER/WEINMAN.. 10/22/2026  
 
 
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