046  
ACUS01 KWNS 120601  
SWODY1  
SPC AC 120559  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1259 AM CDT FRI JUN 12 2026  
 
VALID 121200Z - 131200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
APPALACHIANS...MID ATLANTIC...AND NORTHEAST...AND ALSO FOR PARTS OF  
THE SOUTH-CENTRAL HIGH PLAINS...  
   
..SUMMARY  
 
STRONG TO SEVERE STORMS CAPABLE OF DAMAGING WINDS ARE POSSIBLE  
ACROSS PARTS OF THE APPALACHIANS, MID ATLANTIC, AND NORTHEAST,  
MAINLY THIS AFTERNOON AND EVENING. SEVERE STORMS WITH A THREAT OF  
HAIL AND SEVERE GUSTS WILL ALSO BE POSSIBLE ACROSS PARTS OF THE  
SOUTH-CENTRAL HIGH PLAINS.  
   
..APPALACHIANS INTO THE MID ATLANTIC AND NORTHEAST  
 
A VIGOROUS MID/UPPER-LEVEL SHORTWAVE TROUGH IS FORECAST TO MOVE  
ACROSS QUEBEC LATER TODAY, WITH WEAK MIDLEVEL HEIGHT FALLS FORECAST  
TO EXTEND SOUTH OF THIS SHORTWAVE INTO PARTS OF THE APPALACHIANS,  
NORTHEAST, AND MID ATLANTIC. THE STRONGEST DEEP-LAYER FLOW WILL  
REMAIN NORTH OF THE INTERNATIONAL BORDER, BUT MODEST EFFECTIVE SHEAR  
(GENERALLY 20-30 KT) WILL OVERLAP RELATIVELY STRONG HEATING AND  
MODEST BUOYANCY ACROSS PARTS OF THE NORTHEAST/MID ATLANTIC.  
SCATTERED OUTFLOW-DRIVEN CLUSTERS MAY DEVELOP WITH TIME AND MOVE  
EASTWARD, WITH AN ATTENDANT THREAT OF DAMAGING WIND AND PERHAPS  
ISOLATED HAIL.  
 
DEEP-LAYER FLOW/SHEAR WILL BE EVEN WEAKER INTO PARTS OF THE SOUTHERN  
MID ATLANTIC/CAROLINAS VICINITY. HOWEVER, VERY STRONG HEATING OF A  
MOIST AIRMASS WILL SUPPORT POTENTIAL FOR SCATTERED THUNDERSTORMS  
WITH DOWNBURST POTENTIAL, AND EVENTUAL EVOLUTION INTO LOOSELY  
ORGANIZED CLUSTERS CAPABLE OF DAMAGING OUTFLOW WINDS FROM AFTERNOON  
INTO AT LEAST THE EARLY EVENING.  
   
..SOUTH-CENTRAL HIGH PLAINS VICINITY  
 
MOIST SOUTHERLY LOW-LEVEL FLOW BENEATH STEEPENING MIDLEVEL LAPSE  
RATES WILL RESULT IN ROBUST DESTABILIZATION FROM THE RATON MESA  
VICINITY INTO THE ADJACENT SOUTH-CENTRAL HIGH PLAINS, WITH MLCAPE  
INCREASING TO NEAR/ABOVE 2000 J/KG BY LATE AFTERNOON. MODEST  
WESTERLY MID/UPPER-LEVEL FLOW WILL SUPPORT EFFECTIVE SHEAR OF 30-35  
KT, CONDITIONALLY SUPPORTIVE OF ORGANIZED CONVECTION. LARGE-SCALE  
ASCENT WILL REMAIN SUBTLE, BUT EVENTUAL STORMS MAY DEVELOP BY LATE  
AFTERNOON NEAR THE HIGHER TERRAIN, AND SPREAD EAST-SOUTHEASTWARD  
WITH TIME.  
 
INITIAL STORMS COULD EVOLVE INTO ISOLATED SUPERCELLS, WITH A THREAT  
OF HAIL, LOCALIZED SEVERE GUSTS, AND POSSIBLY A TORNADO.  
CONSOLIDATING OUTFLOW AND A NOCTURNALLY STRENGTHENING LOW-LEVEL JET  
WILL SUPPORT SOME UPSCALE GROWTH DURING THE EVENING, WITH AN  
ATTENDANT SEVERE-WIND THREAT EXPECTED TO SPREAD ACROSS PARTS OF THE  
SOUTH-CENTRAL HIGH PLAINS.  
 
FARTHER SOUTH, MORE ISOLATED STRONG TO SEVERE STORMS WILL BE  
POSSIBLE ACROSS PARTS OF CENTRAL/EASTERN NM INTO FAR WEST TX, WITH A  
THREAT OF ISOLATED HAIL AND LOCALIZED SEVERE GUSTS.  
   
..UPPER MIDWEST  
 
RELATIVELY LOW-TOPPED CONVECTION MAY DEVELOP LATE THIS AFTERNOON  
FROM THE EASTERN DAKOTAS INTO MN, AS LOW-LEVEL LAPSE RATES STEEPEN  
BENEATH SEASONABLY COOL TEMPERATURES ALOFT. ROBUST  
WEST-NORTHWESTERLY FLOW ALOFT WILL CONDITIONALLY FAVOR SOME STORM  
ORGANIZATION, IF SUFFICIENT BUOYANCY CAN DEVELOP. HOWEVER, MOST  
GUIDANCE DEPICTS MLCAPE GENERALLY BELOW 500 J/KG, WITH AN  
INCONSISTENT SIGNAL FOR WHERE THE DEEPEST CONVECTION MIGHT DEVELOP.  
SOME THREAT FOR MARGINAL HAIL AND/OR LOCALLY DAMAGING WIND COULD  
EVOLVE ACROSS SOME PART OF THIS REGION, AND PROBABILITIES MAY BE  
NEEDED IF CONFIDENCE INCREASES REGARDING SUFFICIENT DESTABILIZATION  
AND STORM COVERAGE.  
   
..PARTS OF NE INTO WESTERN IA  
 
ELEVATED CONVECTION MAY DEVELOP LATE IN THE PERIOD FROM PARTS OF NE  
INTO WESTERN IA, WITHIN A WARM-ADVECTION REGIME TO THE NORTH OF A  
WARM FRONT. GUIDANCE CONTINUES TO VARY REGARDING THE MAGNITUDE OF  
ELEVATED MOISTENING/DESTABILIZATION (WHICH MAY BE AFFECTED BY MCS  
DEVELOPMENT TO THE SOUTH ACROSS KS) AND COVERAGE OF STORMS PRIOR TO  
THE END OF THE FORECAST PERIOD. EFFECTIVE SHEAR WILL BE SUFFICIENT  
FOR AT LEAST MODEST STORM ORGANIZATION AND AN ISOLATED HAIL THREAT,  
IF SUFFICIENT DESTABILIZATION CAN OCCUR. THE AFOREMENTIONED  
UNCERTAINTIES AND LIKELY VERY LATE TIMING OF ANY SEVERE THREAT  
PRECLUDE THE ADDITION OF HAIL PROBABILITIES AT THIS TIME.  
   
..PARTS OF OK/NORTH TX  
 
IN THE WAKE OF MORNING CONVECTION, ROBUST REDEVELOPMENT CANNOT BE  
RULED OUT ACROSS PARTS OF OK/NORTH TX, NEAR A OUTFLOW-INFLUENCED  
SURFACE BOUNDARY. GUIDANCE VARIES SUBSTANTIALLY REGARDING THE  
COVERAGE/LOCATION OF STORMS THROUGH MID MORNING, RESULTING IN  
CONSIDERABLE UNCERTAINTY. MODERATE TO STRONG BUOYANCY AND MODEST  
DEEP-LAYER SHEAR COULD RESULT IN LOCALIZED HAIL/WIND POTENTIAL, BUT  
CONFIDENCE IN BOUNDARY PLACEMENT AND DIURNAL STORM COVERAGE IS TOO  
LOW FOR PROBABILITIES AT THIS TIME.  
 
..DEAN/WEINMAN.. 06/12/2026  
 
 
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