124  
ACUS01 KWNS 051244  
SWODY1  
SPC AC 051242  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0742 AM CDT TUE AUG 05 2025  
 
VALID 051300Z - 061200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF  
NORTH AND SOUTH DAKOTA...  
   
..SUMMARY  
 
THUNDERSTORMS ASSOCIATED WITH A THREAT FOR SEVERE GUSTS AND LARGE  
HAIL WILL BE POSSIBLE ACROSS PARTS OF THE DAKOTAS TODAY INTO THIS  
EVENING.  
   
..NORTHERN PLAINS  
 
WARM-AIR ADVECTION SHOWERS AND THUNDERSTORMS ARE ONGOING THIS  
MORNING ACROSS THE WESTERN DAKOTAS, WHERE THE WESTERN EDGE OF THE  
LOW-LEVEL JET OVERLAPS THE EASTERN EDGE OF THE STEEP MID-LEVEL LAPSE  
RATES. THESE STORMS WILL LIKELY CONTINUE NORTHEASTWARD THIS MORNING,  
PERHAPS EVEN EXPANDING IN COVERAGE, AS THE LOW-LEVEL JET PERSISTS  
AND LARGE-SCALE ASCENT ATTENDANT TO AN APPROACHING SHORTWAVE TROUGH  
STRENGTHENS. OCCASIONALLY STRONG UPDRAFTS COULD PRODUCE HAIL AND A  
DAMAGING GUST OR TWO.  
 
CLOUD COVER AND OUTFLOW ASSOCIATED WITH THESE STORMS COULD RESULT IN  
AN EFFECTIVE WARM FRONT EXTENDING FROM A WEAK LOW OVER WESTERN SD  
EASTWARD ACROSS CENTRAL AND EASTERN SD. THE EXACT LOCATION AND  
SHARPNESS OF THIS FRONT REMAIN UNCERTAIN. GIVEN THAT THE SHORTWAVE  
TROUGH WILL LIKELY REMAIN WELL WEST OF THE REGION, LOW-LEVEL  
CONVERGENCE NEAR THIS BOUNDARY AS WELL AS THE SURFACE LOW SHOULD  
BOTH BE AREAS WHERE CONVECTIVE INITIATION IS MOST LIKELY THIS  
AFTERNOON. AMPLE BUOYANCY AND VERTICAL SHEAR WILL BE IN PLACE FOR  
SUPERCELLS WITH THE INITIAL DEVELOPMENT, WITH LARGE HAIL AND  
DAMAGING GUSTS AS THE PRIMARY RISKS. STRONGER LOW TO MID-LEVEL FLOW  
MAY BE IN PLACE ACROSS EASTERN SD, CONTRIBUTING TO GREATER LOW-LEVEL  
SHEAR AND RELATIVELY HIGHER TORNADO POTENTIAL. PRIMARY CONCERN  
ACROSS EASTERN SD IS WHETHER OR NOT THE WARMER LOW TO MID-LEVEL  
TEMPERATURES INHIBIT THE DEVELOPMENT OF MATURE UPDRAFTS.  
 
ONE OTHER SCENARIO THAT SEEMS PLAUSIBLE IS FOR STORMS ON SOUTHERN  
PERIPHERY THE ONGOING CLUSTER TO BECOME INCREASINGLY SURFACE BASED  
AS THEY MOVE EASTWARD/NORTHEASTWARD WITH TIME. GIVEN CURRENT TRENDS  
AND RECENT GUIDANCE, THIS WOULD MOST LIKELY OCCUR ALONG THE EASTERN  
ND/SD BORDER AFTER 20Z. AS PREVIOUSLY MENTIONED, HAIL IS POSSIBLE  
WITHIN THIS CLUSTER THROUGHOUT THE DAY, BUT THE TRANSITION TO A MORE  
SURFACE-BASED CHARACTER COULD INTRODUCE THE THREAT FOR STRONGER  
GUSTS AS WELL.  
 
A STRENGTHENING LOW-LEVEL JET COUPLED WITH PERSISTENT MID-LEVEL  
WESTERLIES SUPPORT THE POTENTIAL FOR UPSCALE GROWTH IN A  
EAST-SOUTHEASTWARD PROGRESSING MCS. DAMAGING GUSTS WILL BE POSSIBLE  
WITH THIS MCS, PARTICULARLY OVER SD, BUT INCREASING LOW-LEVEL  
STABILITY SHOULD RESULT IN A GRADUALLY DIMINISHING SEVERE POTENTIAL  
WITH EASTWARD/SOUTHEASTWARD EXTEND INTO NORTHEAST NE, NORTHWEST IA,  
AND SOUTHWEST MN.  
 
..MOSIER/BENTLEY.. 08/05/2025  
 
 
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