487  
ACUS48 KWNS 040848  
SWOD48  
SPC AC 040846  
 
DAY 4-8 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0346 AM CDT THU SEP 04 2025  
 
VALID 071200Z - 121200Z  
   
..DISCUSSION
 
 
A SEASONALLY COOL AND DRY CONTINENTAL AIRMASS WILL BE IN PLACE  
ACROSS MUCH OF THE EASTERN US AT THE START OF THE FORECAST PERIOD,  
RESULTING IN LOW SEVERE POTENTIAL. BY MONDAY/DAY-5, THE SURFACE HIGH  
PRESSURE RESPONSIBLE FOR THIS AIRMASS WILL HAVE BEGUN TO MOVE EAST  
ALLOWING RETURN FLOW TO BECOME ESTABLISHED ACROSS THE PLAINS. AT THE  
SAME TIME, LEE TROUGHING IN RESPONSE TO A WESTERN US LONGWAVE TROUGH  
WILL REINFORCE THE RETURN FLOW REGIME.  
 
AS THE MOISTURE IS DRAWN NORTHWARD INTO THE PLAINS, STEEP LAPSE  
RATES WILL ADVECT OUT INTO THE PLAINS FROM THE HIGHER ELEVATIONS TO  
THE WEST. THIS COMBINATION OF MOISTENING LOW-LEVELS AND STEEP  
MIDLEVEL LAPSE RATES WILL SUPPORT INCREASING BUOYANCY PROFILES  
THROUGH THE WEEK.  
 
ANY SUBTLE SHORTWAVE TROUGH THAT EJECTS OUT OF THE WESTERN TROUGH  
AND EMERGES INTO THE CENTRAL AND NORTHERN PLAINS WILL HAVE AN  
OPPORTUNITY TO TAP INTO THIS MOIST, BUOYANT ATMOSPHERE. THE RESULT  
WOULD BE AT LEAST SOME POTENTIAL FOR THUNDERSTORMS, SOME OF WHICH  
COULD BE SEVERE. HOWEVER PREDICTABILITY OF THESE KINDS OF SUBTLE  
FEATURES IS TOO POOR AT THESE LEAD TIMES TO ATTEMPT TO HIGHLIGHT  
FAVORED DAYS OR CORRIDORS, THUS PREDICTABILITY REMAINS TOO LOW FOR  
UNCONDITIONAL PROBABILITIES.  
 
..MARSH.. 09/04/2025  
 
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