209  
ACUS02 KWNS 120601  
SWODY2  
SPC AC 120600  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0100 AM CDT WED AUG 12 2026  
 
VALID 131200Z - 141200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR THE COLORADO  
FRONT RANGE AND CENTRAL HIGH PLAINS EASTWARD INTO PARTS OF THE  
MIDWEST AND OHIO VALLEY...  
   
..SUMMARY
 
 
ISOLATED SEVERE STORMS ARE POSSIBLE ON THURSDAY FROM THE COLORADO  
FRONT RANGE AND CENTRAL HIGH PLAINS INTO THE OHIO VALLEY.  
   
..SYNOPSIS
 
 
SOME AMPLIFICATION OF THE UPPER-LEVEL PATTERN IS EXPECTED ON  
THURSDAY ACROSS THE CENTRAL/EASTERN CONUS. AN UPPER RIDGE INITIALLY  
OVER THE LOWER MS VALLEY IS FORECAST TO EXPAND AND BUILD NORTHWARD  
INTO PARTS OF THE GREAT PLAINS. TO THE EAST OF BUILDING RIDGE, A  
SEASONABLY STRONG MID/UPPER-LEVEL SHORTWAVE TROUGH IS FORECAST TO  
MOVE SOUTHEASTWARD ACROSS THE GREAT LAKES TOWARDS THE NORTHEAST. A  
SURFACE LOW IS FORECAST TO REMAIN IN PLACE ACROSS THE SOUTH-CENTRAL  
PLAINS. A NEARLY STATIONARY FRONT IS FORECAST TO EXTEND  
EAST-NORTHEAST OF THE LOW TOWARD THE LOWER MO VALLEY, AND THEN  
EAST-SOUTHEASTWARD TOWARD THE LOWER OH VALLEY.  
   
..CENTRAL PLAINS INTO PARTS OF THE MIDWEST/OHIO VALLEY
 
 
ISOLATED SEVERE POTENTIAL REMAINS EVIDENT IN THE VICINITY OF THE  
SURFACE FRONT ON THURSDAY, THOUGH CONFIDENCE IN THE DETAILS REMAINS  
LOW. ELEVATED CONVECTION AND POSSIBLY A REMNANT MCS MAY BE ONGOING  
AT THE START OF THE PERIOD FROM EASTERN NE INTO PARTS OF IA/NORTHERN  
MO. DEPENDING ON THE EXTENT TO WHICH THE EARLY-DAY CONVECTION CAN  
PROPAGATE WITHIN THE RICH MOISTURE AND MODERATE TO STRONG BUOYANCY  
ALONG THE FRONTAL ZONE, SOME SEVERE THREAT COULD SPREAD  
EAST-SOUTHEASTWARD TOWARD THE LOWER OH VALLEY THROUGH THE DAY.  
 
OTHERWISE, ISOLATED STORMS MAY DEVELOP NEAR/NORTH OF THE FRONT  
THROUGH THE DAY, WITH AN INCREASE IN COVERAGE EXPECTED THURSDAY  
EVENING WITHIN A WARM-ADVECTION REGIME. GENERALLY MODEST AND  
FRONT-PARALLEL MID/UPPER-LEVEL FLOW MAY LEAD TO TRAINING STORMS AND  
A TENDENCY FOR CONVECTION TO BE UNDERCUT OR GENERALLY REMAIN  
SOMEWHAT ELEVATED. HOWEVER, DEEP-LAYER SHEAR WILL STILL BE MODESTLY  
SUPPORTIVE OF ORGANIZED CONVECTION WITHIN THE MOIST AND UNSTABLE  
ENVIRONMENT, WITH SOME POTENTIAL FOR ISOLATED DAMAGING GUSTS AND  
HAIL.  
   
..CO FRONT RANGE INTO THE ADJACENT HIGH PLAINS
 
 
TO THE NORTH/NORTHWEST OF THE PRIMARY SURFACE LOW, MOIST EASTERLY  
LOW-LEVEL FLOW WILL SUPPORT MODERATE TO LOCALLY STRONG  
DESTABILIZATION FROM THE CO FRONT RANGE INTO PARTS OF THE CENTRAL  
HIGH PLAINS. DEEP-LAYER FLOW WILL GENERALLY REMAIN MODEST, BUT  
VEERING WIND PROFILES WILL PROVIDE SUFFICIENT EFFECTIVE SHEAR FOR  
SOME STORM ORGANIZATION. ISOLATED HAIL AND LOCALLY SEVERE GUSTS WILL  
BE POSSIBLE WITH THE STRONGEST STORMS IN THIS REGION.  
ISOLATED TO WIDELY SCATTERED STORMS WILL ALSO BE POSSIBLE WITHIN THE  
HOT AND WELL-MIXED REGIME NEAR/SOUTH OF THE FRONT AND SURFACE LOW.  
WEAK DEEP-LAYER SHEAR SHOULD LIMIT STORM ORGANIZATION IN THIS  
REGIME, BUT STEEP LOW-LEVEL LAPSE RATES COULD SUPPORT LOCALIZED  
SEVERE GUSTS.  
   
..NORTHEAST
 
 
SEASONABLY STRONG MID/UPPER-LEVEL FLOW WILL OVERSPREAD THE NORTHEAST  
ON THURSDAY. HOWEVER, LOW-LEVEL FLOW WILL REMAIN RATHER WEAK, AND  
GENERALLY MODEST MOISTURE AND LAPSE RATES WILL LIMIT  
DESTABILIZATION. MLCAPE OF 500-1000 J/KG WILL SUPPORT DEVELOPMENT OF  
WIDELY SCATTERED THUNDERSTORMS ACROSS NORTHERN NEW ENGLAND. THERE  
WILL BE SOME DISPLACEMENT BETWEEN THE STRONGEST DEEP-LAYER FLOW AND  
MORE FAVORABLE BUOYANCY. SMALL HAIL AND GUSTY WINDS COULD ACCOMPANY  
THE STRONGEST STORMS, BUT CONFIDENCE IN SUFFICIENT DESTABILIZATION  
REMAINS TOO LOW FOR SEVERE PROBABILITIES AT THIS TIME.  
   
..SOUTHEAST
 
 
THUNDERSTORM DEVELOPMENT IS EXPECTED ACROSS PARTS OF AL/GA/SC ON  
THURSDAY, WITHIN A VERY WARM AND MOIST ENVIRONMENT. GUIDANCE VARIES  
REGARDING THE EXTENT TO WHICH EARLY-DAY CONVECTION AND RELATED  
OUTFLOW MOVE INTO THE REGION FROM THE NORTH, AND THE INFLUENCE ANY  
SUCH CONVECTION/OUTFLOW WOULD HAVE ON STORM DEVELOPMENT AND  
EVOLUTION LATER IN THE DAY. IN GENERAL, DEEP-LAYER FLOW/SHEAR WILL  
BE WEAK, BUT THE VERY WARM AND MOIST ENVIRONMENT COULD SUPPORT  
LOCALIZED DOWNBURST POTENTIAL. CONFIDENCE IN AN ORGANIZED SEVERE  
THREAT IS CURRENTLY LOW, BUT IF TRENDS SUPPORT THE PRESENCE OF ANY  
OUTFLOW BOUNDARIES OR REMNANT MCVS EMANATING FROM UPSTREAM, THEN  
WIND PROBABILITIES MAY EVENTUALLY BE NEEDED FOR SOME PART OF THIS  
REGION.  
   
..GREAT BASIN
 
 
STORM DEVELOPMENT IS AGAIN EXPECTED ACROSS PARTS OF THE GREAT BASIN  
ON THURSDAY AFTERNOON, WITH COVERAGE POTENTIALLY AIDED BY A MIDLEVEL  
TROUGH APPROACHING THE REGION FROM CENTRAL/SOUTHERN CA. DEEP-LAYER  
SHEAR WILL REMAIN MODEST AT BEST, BUT FAVORABLE LAPSE RATES AND  
COOLING TEMPERATURES ALOFT COULD SUPPORT RELATIVELY VIGOROUS  
UPDRAFTS WITH POTENTIAL FOR LOCALIZED STRONG TO SEVERE GUSTS.  
UNCERTAINTY REMAINS REGARDING THE ORGANIZATION OF ANY SEVERE THREAT,  
BUT WIND PROBABILITIES MAY EVENTUALLY BE NEEDED FOR THIS AREA AS  
WELL.  
 
..DEAN.. 08/12/2026  
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab SPC Page Main Text Page