765  
ACUS01 KWNS 051624  
SWODY1  
SPC AC 051622  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1122 AM CDT SAT SEP 05 2026  
 
VALID 051630Z - 061200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF  
THE CENTRAL APPALACHIANS INTO SOUTHERN VIRGINIA AND THE CAROLINAS...  
   
..SUMMARY  
 
STRONG TO SEVERE THUNDERSTORMS CAPABLE OF PRODUCING SCATTERED  
DAMAGING WINDS SHOULD OCCUR THIS AFTERNOON/EVENING ACROSS PARTS OF  
THE CENTRAL APPALACHIANS INTO SOUTHERN VIRGINIA AND THE CAROLINAS.  
ISOLATED LARGE HAIL AND SEVERE WINDS MAY ALSO OCCUR OVER PARTS OF  
THE NORTHERN/CENTRAL PLAINS THROUGH TONIGHT.  
 
...OHIO VALLEY/CENTRAL APPALACHIANS INTO THE MID-ATLANTIC AND  
CAROLINAS...  
AN EARLIER MCS ACROSS THE OH VALLEY HAS WEAKENED AS IT CROSSED/MOVED  
EASTWARD OVER THE CENTRAL APPALACHIANS. THE STRONGEST REMAINING  
CONVECTIVE SEGMENT IS ONGOING LATE THIS MORNING ACROSS PARTS OF  
SOUTHWEST VA/NORTHEAST TN. ROBUST DESTABILIZATION IS EXPECTED TO  
CONTINUE THIS AFTERNOON DOWNSTREAM OF THIS ACTIVITY ACROSS SOUTHERN  
VA INTO THE CAROLINAS, WITH MLCAPE PEAKING AROUND 2500-3500 J/KG  
OVER CENTRAL/EASTERN NC. THIS REGION WILL BE ON THE SOUTHERN  
PERIPHERY OF MODESTLY ENHANCED MID-LEVEL WEST-NORTHWESTERLY FLOW,  
AND SUFFICIENT DEEP-LAYER SHEAR WILL BE PRESENT TO MAINTAIN SOME  
CONVECTIVE ORGANIZATION.  
 
CURRENT EXPECTATIONS ARE FOR ONE OR MORE THUNDERSTORM CLUSTERS TO  
GRADUALLY INCREASE IN INTENSITY THIS AFTERNOON AS THEY SPREAD  
EASTWARD ACROSS SOUTHERN VA AND CENTRAL/EASTERN NC, WITH SOME  
UNCERTAINTY WHETHER THE ONGOING CONVECTION WILL RESTRENGTHEN, OR IF  
NEW DEVELOPMENT WILL OCCUR ALONG ITS OUTFLOW. REGARDLESS, LATEST  
GUIDANCE AND OBSERVATIONAL TRENDS STILL SUGGEST THAT A RELATIVELY  
GREATER THREAT FOR DAMAGING WINDS SHOULD EXIST THIS AFTERNOON ACROSS  
CENTRAL/EASTERN NC AND VICINITY, WHERE THE GREATEST THUNDERSTORM  
COVERAGE, MAXIMA IN MLCAPE/DCAPE, AND STEEPENED LOW-LEVEL LAPSE  
RATES ARE FORECAST. HAVE THEREFORE INTRODUCED HIGHER SEVERE WIND  
PROBABILITIES (30% AREA) ACROSS THIS REGION. ISOLATED HAIL MAY ALSO  
OCCUR WITH THE STRONGEST CORES THAT CAN DEVELOP, ALTHOUGH MID-LEVEL  
LAPSE RATES ARE EXPECTED TO REMAIN RATHER POOR. SEVERE POTENTIAL  
SHOULD GRADUALLY WANE THIS EVENING WITH THE LOSS OF DAYTIME HEATING,  
AND AS CONVECTION MOVES OFFSHORE.  
 
FARTHER WEST, OUTFLOW FROM THE MORNING THUNDERSTORMS MAY SERVE AS A  
FOCUS FOR RENEWED THUNDERSTORM DEVELOPMENT THIS AFTERNOON FROM PARTS  
OF THE OH VALLEY SOUTHEASTWARD INTO THE TN VALLEY. THIS REGION WILL  
BE DISPLACED FROM THE STRONGER FLOW ALOFT PRESENT OVER THE  
MID-ATLANTIC/NORTHEAST, WITH WEAK DEEP-LAYER SHEAR EXPECTED. STILL,  
SOME RISK FOR ISOLATED DAMAGING WINDS MAY EXIST WITH ANY LOOSELY  
ORGANIZED CELLS/CLUSTERS THAT CAN DEVELOP GIVEN THE PRESENCE OF  
MODERATE TO LOCALLY STRONG INSTABILITY.  
   
..NORTHERN/CENTRAL PLAINS  
 
A HIGHLY AMPLIFIED MID/UPPER-LEVEL RIDGE WILL REMAIN ANCHORED OVER  
THE CENTRAL CONUS INTO SOUTH-CENTRAL CANADA THROUGH THE PERIOD, WITH  
GENERALLY NEUTRAL TO WEAKLY RISING MID-LEVEL HEIGHTS EXPECTED OVER  
THE NORTHERN/CENTRAL PLAINS. ONGOING ELEVATED CELLS ACROSS NORTHERN  
ND MAY CONTINUE TO POSE AN ISOLATED SEVERE HAIL THREAT IN THE SHORT  
TERM, BUT WEAKENING LOW-LEVEL WARM ADVECTION SHOULD TEND TO RESULT  
IN A FURTHER DECREASE IN INTENSITY WITH THIS ACTIVITY. OTHERWISE,  
ADDITIONAL ISOLATED TO PERHAPS WIDELY SCATTERED HIGH-BASED  
THUNDERSTORMS MAY DEVELOP THIS AFTERNOON ALONG/EAST OF A SURFACE LEE  
TROUGH OVER THE NORTHERN/CENTRAL PLAINS. WHILE MID-LEVEL FLOW AND  
RELATED EFFECTIVE BULK SHEAR SHOULD REMAIN WEAK, OCCASIONAL SEVERE  
GUSTS MAY STILL OCCUR WITH CONVECTIVE DOWNDRAFTS GIVEN A WELL-MIXED  
BOUNDARY LAYER. SOME RISK FOR HAIL AND GUSTY WINDS MAY ALSO EXIST  
WITH ELEVATED CONVECTION THAT SHOULD EVENTUALLY DEVELOP TONIGHT INTO  
EARLY SUNDAY MORNING IN A RENEWED/MODEST LOW-LEVEL WARM ADVECTION  
REGIME.  
   
..WESTERN MONTANA  
 
TO THE EAST OF A CLOSED MID-LEVEL LOW OVER WA/OR, A BELT OF ENHANCED  
SOUTHWESTERLY MID/UPPER-LEVEL WINDS WILL EXTEND ACROSS THE NORTHERN  
ROCKIES. GRADUALLY INCREASING MOISTURE AND LARGE-SCALE ASCENT ALOFT  
ASSOCIATED WITH A WEAK/EMBEDDED SHORTWAVE TROUGH ARE EXPECTED TO  
SUPPORT AN INCREASE IN ISOLATED THUNDERSTORMS THIS  
AFTERNOON/EVENING. LAPSE RATES THROUGH LOW/MID LEVELS WILL BE STEEP  
WITH STRONG DEEP-LAYER SHEAR PRESENT, BUT MODEST LOW-LEVEL MOISTURE  
SHOULD LIMIT MLCAPE TO GENERALLY LESS THAN 500 J/KG. THE POTENTIAL  
FOR SEVERE WIND GUSTS STILL APPEARS TOO LOW TO JUSTIFY INCLUDING 5%  
WIND PROBABILITIES AT THIS TIME.  
 
..GLEASON/THORNTON.. 09/05/2026  
 
 
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