915  
ACUS01 KWNS 040602  
SWODY1  
SPC AC 040600  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0100 AM CDT SAT JUL 04 2026  
 
VALID 041200Z - 051200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE  
MID-ATLANTIC...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF  
THE CENTRAL/SOUTHERN PLAINS...  
   
..SUMMARY
 
 
CLUSTERS OF STORMS WILL MOVE ACROSS PARTS OF THE ALLEGHENY PLATEAU  
INTO MID ATLANTIC, WITH POTENTIAL FOR WIDESPREAD DAMAGING WIND.  
ADDITIONAL THUNDERSTORMS ARE EXPECTED ACROSS THE GREAT PLAINS  
SATURDAY AFTERNOON AND EVENING, POSING A RISK FOR DAMAGING WIND  
GUSTS. LARGE HAIL IS ALSO POSSIBLE ACROSS THE GREAT PLAINS.  
   
..SYNOPSIS
 
 
HEIGHT RISES WILL CONTINUE ACROSS THE WESTERN US, WITH MORE ZONAL  
FLOW ACROSS THE CENTRAL US AND UPPER-LEVEL TROUGHING ACROSS THE  
NORTHEAST AND QUEBEC/ONTARIO. A MODEST BELT OF WESTERLY FLOW AROUND  
30-40 KTS WILL MOVE THROUGH THE TROUGH IN THE  
NORTHEAST/MID-ATLANTIC. A COMPACT SHORTWAVE TROUGH WITH ENHANCED  
WESTERLY FLOW WILL MOVE THROUGH THE FLOW ACROSS THE CENTRAL PLAINS.  
   
..EASTERN OHIO VALLEY INTO THE MID-ATLANTIC
 
 
ACTIVITY WILL LIKELY BE ONGOING ACROSS SOME PORTION OF NORTHERN PA  
INTO NORTHERN NJ THIS MORNING. THIS WILL LIKELY CONTRIBUTE TO  
LINGERING CLOUD COVER AND MORE MUTED DAYTIME HEATING/RECOVERY WITH  
NORTHERN EXTENT. SOUTH OF THE MORNING PRECIPITATION, STRONG DAYTIME  
HEATING AND WARMING IS EXPECTED, WITH TEMPERATURES CLIMBING INTO THE  
90S TO 100S F. A PLUME OF STEEP MID-LEVEL LAPSE RATES IS ALREADY IN  
PLACE ACROSS THE REGION FROM WV INTO VA/MD/NJ. WITH DAYTIME HEATING,  
LOW-LEVEL LAPSE RATES ARE EXPECTED TO INCREASE WITH MODERATE TO  
STRONG INSTABILITY BY THE AFTERNOON. DEEP LAYER SHEAR PROFILES WILL  
BE GENERALLY WEAK, WITH BETTER SHEAR TO THE NORTH. NONETHELESS,  
SEVERAL THUNDERSTORM CLUSTERS ARE EXPECTED TO DEVELOP ACROSS THE  
BLUE RIDGE MOUNTAINS/SHENANDOAH VALLEY MOVING NORTH AND EASTWARD  
THOUGH THE AFTERNOON. THESE WILL HAVE THE POTENTIAL TO PRODUCE  
WIDESPREAD DAMAGING WIND, ESPECIALLY IF CLUSTERS CAN GROW UPSCALE  
AND DEVELOP STRONG COLD POOLS.  
 
ADDITIONAL CLUSTERS ARE LIKELY IN THE WAKE OF MORNING CONVECTION  
FURTHER NORTH. INSTABILITY WILL BE LESS, BUT SUFFICIENT DEEP LAYER  
SHEAR MAY SUPPORT ONE OR MORE CLUSTERS CAPABLE OF DAMAGING WIND.  
   
..CENTRAL/SOUTHERN PLAINS
 
 
EVOLUTION OF THUNDERSTORMS ACROSS THE CENTRAL/SOUTHERN PLAINS WILL  
BE DEPENDENT ON EVOLUTION OF MORNING CONVECTION ACROSS NORTHERN  
KANSAS. ONE OR MORE MCVS MAY DEVELOP AND DRIFT SOUTH AND EASTWARD,  
WHICH WILL HAVE IMPACTS ON THE EXACT REGION THAT THUNDERSTORMS  
REDEVELOP BY THE AFTERNOON. GUIDANCE SUGGESTS THAT THE CORRIDOR OF  
HIGHEST PROBABILITY OF DEVELOPMENT WILL BE ACROSS SOUTHERN KANSAS  
INTO NORTHERN OKLAHOMA. WITHIN THIS REGION, WIDELY SCATTERED  
THUNDERSTORM ACTIVITY IS EXPECTED TO DEVELOP BY THE AFTERNOON, WITH  
INITIAL SUPERCELLS CAPABLE OF LARGE TO VERY LARGE HAIL AND PERHAPS A  
TORNADO. THESE WILL EVENTUALLY CLUSTER AND GROW UPSCALE, WITH A  
LIKELY MCS MOVING SOUTH INTO OKLAHOMA BY THE EVENING AND AN INCREASE  
IN DAMAGING WIND POTENTIAL.  
 
MORE ISOLATED SUPERCELL DEVELOPMENT IS EXPECTED FROM THE OK/TX  
PANHANDLES NORTHWARD INTO EASTERN CO/WESTERN KS/WESTERN NE. DEEPLY  
MIXED PROFILES AND SUFFICIENT DEEP LAYER SHEAR SHOULD SUPPORT  
POTENTIAL FOR BOTH LARGE HAIL AND DAMAGING WIND.  
 
...MIDWEST INTO THE LOWER MISSOURI VALLEY AND WESTERN/CENTRAL OHIO  
VALLEY...  
THERE IS LESS CONFIDENCE IN EVOLUTION OF AFTERNOON THUNDERSTORMS  
INTO THE MISSOURI VALLEY AND WESTERN/CENTRAL OHIO VALLEY. MODERATE  
TO STRONG INSTABILITY WILL BE IN PLACE WITH GENERALLY WEAK FLOW/DEEP  
LAYER SHEAR. GUIDANCE SUGGESTS THAT SEVERAL CLUSTERS OF  
THUNDERSTORMS MAY DEVELOP AND SPREAD EASTWARD WITH DAMAGING  
WIND/DOWNBURST POTENTIAL. THIS WILL LIKELY BE FOCUSED IN MORE  
MESOSCALE CORRIDORS WHERE RESIDUAL OUTFLOW RESIDES.  
 
..THORNTON/MOORE.. 07/04/2026  
 

 
 
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