999  
ACUS48 KWNS 210900  
SWOD48  
SPC AC 210859  
 
DAY 4-8 CONVECTIVE OUTLOOK RESENT 1  
NWS STORM PREDICTION CENTER NORMAN OK  
0359 AM CDT SAT MAY 21 2022  
 
VALID 241200Z - 291200Z  
   
..DISCUSSION
 
   
..TUESDAY/DAY 4 TO THURSDAY/DAY 6
 
 
AN UPPER-LEVEL TROUGH IS FORECAST TO MOVE INTO THE SOUTHERN HIGH  
PLAINS ON TUESDAY. AHEAD OF THE TROUGH, A MOIST AIRMASS WILL BE  
LOCATED ACROSS PARTS OF CENTRAL AND EAST TEXAS, WHERE MODERATE  
INSTABILITY IS EXPECTED TO DEVELOP BY AFTERNOON. THUNDERSTORM  
FORMATION WILL BE POSSIBLE OVER A LARGE PART OF THE SOUTHERN PLAINS  
EASTWARD INTO THE LOWER MISSISSIPPI VALLEY. AN MCS MAY ORGANIZE  
ALONG THE NORTHERN EDGE OF THE STRONGER INSTABILITY AND POSE A  
SEVERE THREAT DURING THE AFTERNOON AND EVENING. AT THIS TIME, THERE  
IS A LARGE SPREAD IN THE MODEL SOLUTIONS CONCERNING WHERE THIS MCS  
COULD POTENTIALLY FORM. THIS COMBINED WITH THE FACT THAT MESOSCALE  
INFLUENCES WILL BE A STRONG CONTRIBUTOR TO ANY SEVERE THREAT, MAKES  
FOR A LOT OF UNCERTAINTY. THERE WILL LIKELY BE NEED FOR A SEVERE  
THREAT AREA ONCE THE MODEL SOLUTIONS KEY IN ON A SPECIFIC AREA WITH  
GREATER POTENTIAL.  
 
ON WEDNESDAY, THE UPPER-LEVEL TROUGH IS FORECAST TO MOVE SLOWLY  
EASTWARD ACROSS THE SOUTHERN PLAINS. A MOIST AND UNSTABLE AIRMASS  
SHOULD BE IN PLACE FROM THE TEXAS COASTAL PLAINS EASTWARD INTO THE  
CENTRAL GULF COAST STATES. MOISTURE ADVECTION WILL ALSO TAKE PLACE  
ACROSS THE OHIO AND TENNESSEE VALLEYS. A POTENTIAL FOR STRONG  
THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE ALONG THE NORTHERN EDGE OF  
THE STRONGER INSTABILITY, SOMEWHERE FROM EAST TEXAS EASTWARD INTO  
LOWER MISSISSIPPI VALLEY. OTHER STRONG THUNDERSTORMS COULD FORM  
AHEAD OF A COLD FRONT FROM THE MID MISSISSIPPI VALLEY NORTHEASTWARD  
INTO THE OHIO VALLEY. MESOSCALE INFLUENCES AND THE DISTRIBUTION OF  
INSTABILITY WILL AGAIN HAVE A STRONG IMPACT ANY SEVERE THREAT THAT  
DEVELOPS WEDNESDAY AFTERNOON.  
 
THE UPPER-LEVEL TROUGH IS FORECAST TO MOVE INTO THE LOWER TO MID  
MISSISSIPPI VALLEY ON THURSDAY, AS A MOIST AIRMASS REMAINS TO THE  
EAST OF THE SYSTEM. THUNDERSTORM DEVELOPMENT WILL BE POSSIBLE OVER A  
LARGE AREA FROM THE CENTRAL GULF COAST STATES NORTHWARD INTO THE  
OHIO VALLEY. ISOLATED STRONG THUNDERSTORMS WILL AGAIN BE POSSIBLE  
ALONG THIS CORRIDOR IN AREAS THAT HEAT UP THE MOST, AND IN AREAS  
WHERE MESOSCALE FACTORS ARE FAVORABLE.  
 
FROM TUESDAY TO THURSDAY, PREDICTABILITY IS TOO LOW TO ADD A THREAT  
AREA, DUE TO THE UNCERTAINTIES PREVIOUSLY MENTIONED.  
   
..FRIDAY/DAY 7 AND SATURDAY/DAY 8
 
 
ON FRIDAY AND SATURDAY, THE UPPER-LEVEL SYSTEM IS FORECAST TO MOVE  
SLOWLY EASTWARD TOWARD THE EAST COAST. THUNDERSTORMS WILL AGAIN BE  
POSSIBLE EACH DAY ACROSS A BROAD AREA AHEAD OF THE SYSTEM. ALTHOUGH  
STRONG THUNDERSTORMS WILL BE POSSIBLE IN SOME AREAS OF THE EASTERN  
U.S. EACH AFTERNOON AND EVENING, THE RANGE IN THE FORECAST IS TOO  
FAR OUT TO MAKE ANY SOLID CONCLUSIONS CONCERNING SPECIFIC THREAT  
AREAS.  
 
..BROYLES.. 05/21/2022  
 
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