647  
ACUS48 KWNS 240849  
SWOD48  
SPC AC 240847  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0347 AM CDT SUN SEP 24 2023  
 
VALID 271200Z - 021200Z  
   
..DISCUSSION
 
   
..WEDNESDAY/DAY 4 TO FRIDAY/DAY 6
 
 
FROM WEDNESDAY TO FRIDAY, AN UPPER-LEVEL LOW IS FORECAST TO MOVE  
NORTHEASTWARD ACROSS THE GREAT LAKES REGION, AS AN UPPER-LEVEL RIDGE  
MOVES THROUGH THE NORTH-CENTRAL U.S. AT THE SURFACE, HIGH PRESSURE  
WILL LIKELY REMAIN IN PLACE ACROSS THE EASTERN THIRD OF THE NATION.  
WEAK INSTABILITY IS FORECAST TO DEVELOP ALONG AND NEAR AN  
UPPER-LEVEL TROUGH IN THE OHIO AND TENNESSEE VALLEYS ON WEDNESDAY  
AND THURSDAY, WHERE SCATTERED THUNDERSTORM DEVELOPMENT WILL BE  
POSSIBLE.  
 
FURTHER WEST, ACROSS THE NORTHERN PLAINS, SOUTHWEST MID-LEVEL FLOW  
IS FORECAST TO DEVELOP ON THURSDAY AND FRIDAY. IN RESPONSE,  
LOW-LEVEL MOISTURE WILL LIKELY RETURN NORTHWARD INTO THE NORTHERN  
PLAINS, WHERE A POCKET OF MODERATE INSTABILITY COULD POTENTIALLY  
DEVELOP BY FRIDAY AFTERNOON. ISOLATED TO SCATTERED THUNDERSTORMS,  
ALONG WITH A MARGINAL SEVERE THREAT, WOULD BE POSSIBLE FRIDAY OR  
FRIDAY NIGHT AS DESTABILIZATION OCCURS AND LOW-LEVEL FLOW INCREASES.  
   
..SATURDAY/DAY 7 AND SUNDAY/DAY 8
 
 
FROM SATURDAY INTO SUNDAY, AN UPPER-LEVEL TROUGH IS FORECAST TO MOVE  
INTO THE WESTERN U.S. AS MID-LEVEL FLOW BECOMES MORE  
SOUTH-SOUTHWESTERLY ACROSS THE NORTH-CENTRAL U.S. MODEL FORECASTS  
SUGGEST THAT A POCKET OF MODERATE INSTABILITY WILL BE IN PLACE  
ACROSS THE DAKOTAS ON SATURDAY, AND TO A LESSER EXTENT ON SUNDAY AS  
WELL. ALTHOUGH LARGE-SCALE ASCENT WILL PROBABLY BE WEAK ACROSS THE  
REGION OVER THE WEEKEND, ISOLATED TO SCATTERED THUNDERSTORMS COULD  
STILL DEVELOP, ESPECIALLY IF A BOUNDARY MOVES THROUGH THE REGION, AS  
IS SUGGESTED BY SOME SOLUTIONS. A SEVERE THREAT WOULD BE POSSIBLE,  
ESPECIALLY ON SATURDAY AFTERNOON AND EVENING WHEN INSTABILITY IS  
FORECAST TO BE MAXIMIZED. AT THIS TIME, PREDICTABILITY IS LOW  
CONCERNING ANY POTENTIAL SCENARIO.  
 
..BROYLES.. 09/24/2023  
 
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