099  
ACUS01 KWNS 221627  
SWODY1  
SPC AC 221626  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1126 AM CDT WED MAY 22 2019  
 
VALID 221630Z - 231200Z  
 
...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON  
AND EVENING OVER PARTS OF NORTHEAST OKLAHOMA...SOUTHEAST  
KANSAS...AND WESTERN AND CENTRAL MISSOURI...  
   
..SUMMARY
 
 
SEVERE THUNDERSTORMS ARE FORECAST THIS AFTERNOON INTO EVENING FROM  
CENTRAL AND NORTHEAST OKLAHOMA INTO MISSOURI AND CENTRAL ILLINOIS.  
TORNADOES, LARGE/DAMAGING HAIL AND SEVERE GUSTS ALL ARE POSSIBLE.  
   
..OK TO IL
 
 
GIVEN LATEST MODEL GUIDANCE AND OBSERVATIONAL TRENDS, HAVE OPTED TO  
UPGRADE TO MDT RISK ALONG A NARROW CORRIDOR FROM NORTHEAST OK INTO  
CENTRAL MO. CONSENSUS CONTINUES TO GROW IN MODEL GUIDANCE THAT  
SEVERAL DISCRETE SUPERCELLS WILL DEVELOP ALONG THIS CORRIDOR THIS  
AFTERNOON AND EVENING, AS LOW-LEVEL MOISTURE STREAMS NORTHWARD AND  
SHEAR PROFILES RAPIDLY STRENGTHEN. THE PRIMARY NEGATIVE INDICATOR  
OF A MORE SIGNIFICANT SEVERE WEATHER EVENT INVOLVES THE LARGE SCALE  
PATTERN, AND THE LARGE MIDLEVEL HEIGHT RISES THAT ARE OCCURRING  
THROUGHOUT THE PLAINS. HOWEVER, LATEST WATER VAPOR LOOP AND MODEL  
GUIDANCE SUGGEST VERY SUBTLE SHORTWAVE TROUGHS EMBEDDED IN THE UPPER  
FLOW, WITH ONE CURRENTLY OVER SOUTHWEST OK. THIS FEATURE WOULD  
ARRIVE INTO THE RISK AREA AROUND PEAK HEATING, POTENTIALLY HELPING  
INITIATION. FORECAST SOUNDINGS SUGGEST AN ENVIRONMENT FAVORABLE FOR  
STRONG TORNADOES AND VERY LARGE HAIL AND IF DISCRETE SUPERCELLS CAN  
FORM.  
 
IT IS UNCLEAR HOW FAR SOUTHWEST THE DEVELOPMENT WILL OCCUR INTO  
CENTRAL OK. SEVERAL 12Z CAM SOLUTIONS SUGGEST 1-2 STORMS NEAR OKC  
THAT COULD BE SEVERE IF THEY DEVELOP, WITH A CONDITIONAL RISK OF  
SIGNIFICANT TORNADOES AND HAIL. HOWEVER, CONFIDENCE IN PERSISTENT  
THUNDERSTORMS THAT FAR SOUTHWEST IS LOWER THAN FARTHER NORTHEAST.  
 
STORMS THAT FORM OVER CENTRAL MO WILL SPREAD EASTWARD INTO  
CENTRAL/NORTHERN IL DURING THE EVENING, WITH THE CONTINUED RISK OF  
SUPERCELLS CAPABLE OF LARGE HAIL, DAMAGING WINDS, AND A FEW  
TORNADOES. IT IS UNCLEAR HOW RICH THE LOW-LEVEL MOISTURE WILL BE  
AHEAD OF THE STORMS, BUT SHEAR PROFILES WILL BE QUITE FAVORABLE IN  
THIS AREA.  
 
..HART/KARSTENS.. 05/22/2019  
 

 
 
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