797  
ACUS01 KWNS 030538  
SWODY1  
SPC AC 030536  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1236 AM CDT SUN MAY 03 2026  
 
VALID 031200Z - 041200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF  
NORTHERN/CENTRAL MISSOURI INTO CENTRAL ILLINOIS...  
   
..SUMMARY
 
 
A FEW STRONG THUNDERSTORMS ARE POSSIBLE ACROSS PARTS OF  
NORTHERN/CENTRAL MISSOURI AND CENTRAL ILLINOIS ON SUNDAY.  
   
..SYNOPSIS
 
 
A SHORT-WAVE TROUGH WITH A BELT OF ENHANCED NORTHWESTERLY FLOW  
WITHIN THE BROADER EASTERN US TROUGH WILL OVERSPREAD THE MISSOURI  
VALLEY THROUGH THIS EVENING. A WEAK COLD FRONT WILL EXTEND ACROSS  
PORTIONS OF THE CENTRAL PLAINS INTO THE MISSOURI VALLEY. THIS  
BOUNDARY WILL BE THE FOCUS FOR POTENTIAL ISOLATED THUNDERSTORM  
DEVELOPMENT AS THE SHORT-WAVE MOVES IN ACROSS THE REGION BY THE  
EVENING.  
   
..NORTHERN/CENTRAL MISSOURI INTO CENTRAL ILLINOIS
 
 
MOISTURE QUALITY CONTINUES TO BE A QUESTION WITHIN THE MARGINAL RISK  
AREA AS PREVIOUSLY STATED IN PRIOR OUTLOOKS. SURFACE OBSERVATIONS  
SHOW 50S DEW POINTS HAVE MADE IT AS FAR NORTH AS THE RED RIVER IN  
SOUTHERN OKLAHOMA AS OF LATE SATURDAY EVENING. THERE REMAINS SOME  
QUESTION JUST HOW FAR NORTH (OR DEEP) THIS MOISTURE WILL BE BY LATE  
AFTERNOON ACROSS MISSOURI/ILLINOIS. MOST 00Z GUIDANCE SUGGESTS THAT  
50 F DEW POINTS WILL STEADILY SPREAD INTO MISSOURI THROUGH THE DAY  
TODAY. HOWEVER, AFTERNOON SOUNDING PROFILES SUGGEST THIS MOISTURE TO  
BE THIN AND POTENTIALLY SUBJECT TO MIXING. THROUGH THE AFTERNOON,  
WEAK CONVERGENCE ALONG THE FRONT AND A MID-LEVEL CAPPING INVERSION  
WILL LIKELY PROHIBIT CONVECTIVE DEVELOPMENT. AS THE SHORT-WAVE  
ASCENT ARRIVES IN THE EVENING, 00Z HREF GUIDANCE SUGGEST THAT AT  
LEAST ISOLATED THUNDERSTORMS MAY DEVELOP (AS SEEN IN ENSEMBLE PAINT  
BALLS >40Z DBZ AND IN CALIBRATED THUNDER CHANCES AROUND 40-50%).  
TEMPERATURES ALOFT WILL BE RATHER COLD (AROUND -20 C AT 500 MB).  
EVEN UPPER 40S F DEWPOINTS WILL RESULT IN AROUND 1000 TO PERHAPS  
1500 J/KG MLCAPE BY LATE AFTERNOON/EARLY EVENING. GIVEN STEEPENING  
LAPSE RATE PROFILES AND COLD TEMPERATURES ALOFT, POTENTIAL FOR A FEW  
INSTANCES OF SEVERE HAIL AND STRONG TO SEVERE WINDS WILL BE  
POSSIBLE.  
   
..NORTHERN CALIFORNIA/SOUTHWEST OREGON
 
 
CONVECTION IS POSSIBLE DURING THE AFTERNOON AS MID-LEVEL  
TEMPERATURES COOL IN CLOSE PROXIMITY TO THE UPPER LOW OFF THE COAST.  
FILTERED SURFACE HEATING COULD ALLOW FOR A FEW STRONGER STORMS TO  
DEVELOP. SMALL HAIL AND GUSTY WINDS ARE POSSIBLE. ANVIL-LEVEL FLOW  
WILL BE QUITE WEAK WHICH WILL LIKELY LEAD TO STORMS THAT ARE ONLY  
STRONG BRIEFLY. THE OVERALL SEVERE POTENTIAL APPEARS LOW.  
 
..THORNTON/LYONS.. 05/03/2026  
 

 
 
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