810  
ACUS01 KWNS 020557  
SWODY1  
SPC AC 020555  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1255 AM CDT THU JUL 02 2026  
 
VALID 021200Z - 031200Z  
 
...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS  
OF THE NORTHERN PLAINS INTO THE UPPER MIDWEST...  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THE NORTHERN  
PLAINS INTO PARTS OF THE UPPER GREAT LAKES AND MIDWEST AND OVER THE  
SOUTHERN APPALACHIANS...  
   
..SUMMARY  
 
STRONG TO SEVERE STORMS WILL BE POSSIBLE FROM THE NORTHERN PLAINS  
INTO THE MIDWEST AND GREAT LAKES REGIONS, AS WELL AS ACROSS THE  
SOUTHERN APPALACHIANS ON THURSDAY. ISOLATED STRONG TO SEVERE STORMS  
MAY ALSO OCCUR IN THE TENNESSEE VALLEY, CENTRAL HIGH PLAINS, AND  
PARTS OF THE NORTHEAST.  
   
..SYNOPSIS  
 
THE UPPER LEVEL PATTERN ACROSS THE US WILL BE CHARACTERIZED BY  
TROUGHING ACROSS THE WESTERN US WITH A HIGH AMPLITUDE RIDGE ACROSS  
THE EASTERN US. BETWEEN THESE FEATURES, SEVERAL SHORTWAVE TROUGHS  
WILL ROTATE THROUGH THE FLOW ACROSS THE CENTRAL/NORTHERN PLAINS INTO  
THE MIDWEST. A SURFACE LOW WILL BE LOCATED ACROSS EASTERN MONTANA  
INTO THE WESTERN DAKOTAS, WITH A SURFACE BOUNDARY EXTENDING FROM THE  
NORTHERN PLAINS INTO THE UPPER MIDWEST.  
   
..NORTHERN HIGH PLAINS INTO THE GREAT LAKES AND MIDWEST  
 
EARLY MORNING CONVECTION IS LIKELY ACROSS SOME PORTION OF NORTH  
DAKOTA IN ASSOCIATION WITH A VORT MAX MOVING OUT OF MONTANA. THE  
EVOLUTION OF THIS ACTIVITY WILL LIKELY HAVE IMPLICATIONS ON THE  
EXACT PLACEMENT OF THE SURFACE BOUNDARY BY THIS AFTERNOON ACROSS THE  
DAKOTAS. AFTERNOON THUNDERSTORM DEVELOPMENT IS EXPECTED NEAR THE  
SURFACE LOW AND IN THE VICINITY OF THE SURFACE BOUNDARY/RESIDUAL  
OUTFLOW ACROSS THE DAKOTAS BY THE AFTERNOON. COVERAGE SHOULD  
INCREASE AS A SHORTWAVE MOVES OUT OF MONTANA INTO THE  
AFTERNOON/EVENING WITH INCREASING FORCING FOR ASCENT. ACROSS THE  
NORTHERN HIGH PLAINS, STRONG DAYTIME HEATING AMID STEEP LOW TO  
MID-LEVEL LAPSE RATES WILL SUPPORT MODERATE TO STRONG INSTABILITY.  
THIS IN COMBINATION WITH DEEP-LAYER SHEAR AROUND 40-45 KTS WILL  
SUPPORT INITIAL SUPERCELLS CAPABLE OF LARGE TO VERY LARGE HAIL AND  
DAMAGING WIND. THROUGH TIME, BOUNDARY PARALLEL SHEAR AND LARGE DEW  
POINT SPREADS PROMOTING OUTFLOW DOMINATE STORMS WILL LIKELY SUPPORT  
ONE OR MORE CLUSTERS/BOWING SEGMENTS MOVING SOUTH AND EAST WITH  
TIME, RESULTING IN AN INCREASE IN THE DAMAGING WIND THREAT AND  
POTENTIAL FOR A FEW SIGNIFICANT GUST 75+ MPH.  
   
..SOUTHERN APPALACHIANS INTO THE TENNESSEE VALLEY  
 
A VERY MOIST AND UNSTABLE AIR MASS IS EXPECTED TO BE IN PLACE ACROSS  
THE SOUTHERN APPALACHIANS INTO THE TENNESSEE VALLEY THIS AFTERNOON.  
WIDELY SCATTERED THUNDERSTORMS ARE EXPECTED TO DEVELOP ACROSS THE  
HIGH TERRAIN, WITH TENDENCY TO CLUSTER ALONG OUTFLOWS. CONSENSUS IS  
HIGHEST ACROSS THE APPALACHIANS INTO THE TENNESSEE VALLEY FOR A MORE  
FOCUSED CORRIDOR OF DAMAGING WIND POTENTIAL.  
   
..CENTRAL HIGH PLAINS  
 
ISOLATED THUNDERSTORMS ARE EXPECTED TO DEVELOP WITHIN THE LEE TROUGH  
ACROSS THE CENTRAL HIGH PLAINS THIS AFTERNOON. MODERATE INSTABILITY  
OVERLAPPING WITH AROUND 25-30 KTS OF DEEP-LAYER SHEAR WILL SUPPORT  
POTENTIAL FOR A MIX OF SUPERCELLS AND MULTI-CELL CLUSTERS. STEEP  
LOW- TO MID-LEVEL LAPSE RATES AND LARGE TEMPERATURE/DEW POINT  
SPREADS WILL SUPPORT POTENTIAL FOR SEVERE GUSTS. INITIAL SUPERCELLS  
WILL POSE POTENTIAL FOR LARGE HAIL.  
   
..NORTHEAST  
 
NORTHEASTERLY FLOW WITHIN THE NORTHERN PERIPHERY OF THE EASTERN  
RIDGE WILL ALLOW FOR THUNDERSTORM ACTIVITY TO TRACK SOUTHWARD OUT OF  
QUEBEC/ONTARIO ACROSS PORTIONS OF THE NORTHEAST THIS AFTERNOON. THE  
PRESENCE OF MODERATE TO STRONG INSTABILITY AND 30-40 KT  
OF DEEP-LAYER SHEAR WILL BE SUPPORTIVE OF ORGANIZED STORM MODES WITH  
THE PREDOMINANT HAZARD BEING DAMAGING WINDS. HIGHER WIND  
PROBABILITIES AND A LEVEL 2/SLIGHT RISK MAY BE NEEDED WITH  
ADDITIONAL OUTLOOK UPDATES IF A MORE FAVORABLE CORRIDOR OF WIND  
POTENTIAL BECOME CLEARER.  
 
..THORNTON/CHALMERS.. 07/02/2026  
 
 
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