139  
ACUS48 KWNS 110820  
SWOD48  
SPC AC 110818  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0318 AM CDT MON MAY 11 2026  
 
VALID 141200Z - 191200Z  
   
..DISCUSSION
 
   
..THURSDAY/DAY 4 TO SATURDAY/DAY 6
 
 
AT MID-LEVELS, A SHORTWAVE RIDGE IS FORECAST TO PASS EASTWARD  
THROUGH THE NORTH-CENTRAL U.S. ON THURSDAY. A SHORTWAVE TROUGH IS  
FORECAST TO MOVE INTO THE GREAT PLAINS, WITH MOISTURE AND  
INSTABILITY LOCATED IN THE CENTRAL PLAINS. ALTHOUGH MOST OF THE  
AIRMASS IS FORECAST TO BE CAPPED DURING THE DAY, A FEW STORMS WITH  
AN ISOLATED SEVERE THREAT WILL BE POSSIBLE IN AREAS THAT HEAT UP THE  
MOST.  
 
ON FRIDAY, A MID-LEVEL RIDGE IS FORECAST TO MOVE EASTWARD ACROSS THE  
GREAT PLAINS, AS A MOISTURE AND INSTABILITY ADVECTS NORTHEASTWARD  
INTO THE LOWER TO MID MISSOURI VALLEY. ISOLATED TO SCATTERED  
THUNDERSTORMS WILL BE POSSIBLE WITHIN THIS AIRMASS IN THE AFTERNOON  
AND EVENING. HAIL AND ISOLATED SEVERE GUSTS WOULD BE THE PRIMARY  
THREATS.  
 
BY SATURDAY, A WIDE CORRIDOR OF MODERATE INSTABILITY IS FORECAST TO  
BE IN PLACE OVER THE GREAT PLAINS. A SHORTWAVE TROUGH IS FORECAST TO  
MOVE INTO THE CENTRAL U.S. DURING THE AFTERNOON. AHEAD OF THE  
SHORTWAVE, SCATTERED THUNDERSTORMS WILL BE POSSIBLE FROM NORTH TEXAS  
NORTHWARD INTO NEBRASKA. ALONG THE WESTERN EDGE OF THE INSTABILITY  
CORRIDOR, STEEP MID-LEVEL LAPSE RATES AND MODERATE DEEP-LAYER SHEAR  
ARE FORECAST. THE ENVIRONMENT COULD SUPPORT LARGE HAIL, DAMAGING  
WIND GUSTS AND AN ISOLATED TORNADO THREAT IN THE SOUTHERN AND  
CENTRAL PLAINS WHERE INSTABILITY, SHEAR AND LIFT ARE FORECAST TO  
BECOME MAXIMIZED.  
   
..SUNDAY/DAY 7 AND MONDAY/DAY 8
 
 
ON SUNDAY, MID-LEVEL FLOW IS FORECAST TO BE SOUTHWESTERLY OVER THE  
CENTRAL U.S., AS A SHORTWAVE TROUGH MOVES INTO THE GREAT LAKES.  
ANOTHER SHORTWAVE TROUGH IS FORECAST TO MOVE INTO THE NORTHERN HIGH  
PLAINS. FURTHER SOUTH IN THE SOUTHERN AND CENTRAL PLAINS, MODERATE  
TO STRONG INSTABILITY IS FORECAST TO BE IN PLACE BY MIDDAY.  
THUNDERSTORM DEVELOPMENT IS EXPECTED OVER PARTS OF THIS UNSTABLE  
AIRMASS IN THE AFTERNOON AND EVENING. ALTHOUGH UNCERTAINTY EXISTS  
CONCERNING THE LOCATION OF THE GREATEST SEVERE THREAT, SOME  
SOLUTIONS SUGGEST POTENTIAL FOR A LARGE COMPLEX OF STORMS FROM  
EASTERN KANSAS INTO MISSOURI. AT THIS TIME, TOO MUCH UNCERTAINTY  
EXISTS FOR THE ADDITION OF A SEVERE THREAT AREA.  
 
ON MONDAY, A FRONT IS FORECAST TO ADVANCE SOUTHEASTWARD ACROSS THE  
CENTRAL U.S. AHEAD OF THIS FRONT, ISOLATED SEVERE STORMS WILL BE  
POSSIBLE NEAR AN AXIS OF INSTABILITY IN THE AFTERNOON AND EVENING.  
HOWEVER, MODEL SPREAD IS RELATIVELY LARGE CONCERNING THE TIMING OF  
FEATURES AT THIS EXTENDED RANGE.  
 
..BROYLES.. 05/11/2026  
 
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