953  
ACUS02 KWNS 291712  
SWODY2  
SPC AC 291710  
 
DAY 2 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
1210 PM CDT SUN JUN 29 2025  
 
VALID 301200Z - 011200Z  
 
...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE  
MIDWEST INTO THE OHIO VALLEY...THE MID-ATLANTIC...AND ALONG THE  
CALIFORNIA/OREGON BORDER...  
   
..SUMMARY  
 
SCATTERED STRONG TO SEVERE THUNDERSTORMS REMAIN POSSIBLE ACROSS  
PARTS OF THE OHIO VALLEY, MIDWEST AND THE MID-ATLANTIC TOMORROW  
(MONDAY). A COUPLE OF SEVERE THUNDERSTORMS ALSO CANNOT BE RULED OUT  
OVER PARTS OF THE PACIFIC NORTHWEST.  
   
..SYNOPSIS  
 
A MID-LEVEL TROUGH WILL AMPLIFY WHILE TRAVERSING THE GREAT LAKES AND  
OHIO VALLEY REGIONS, AS UPPER RIDGING BUILDS OVER THE PLAINS STATES  
AND AN UPPER-LEVEL LOW IMPINGES ON THE CALIFORNIA COASTLINE TOMORROW  
(MONDAY). A COLD FRONT WILL ACCOMPANY THE MIDWEST MID-LEVEL TROUGH,  
AND IS POISED TO PROGRESS ACROSS THE MID-MS AND OH VALLEY REGIONS  
WHILE DRAPING ACROSS THE SOUTHERN PLAINS THROUGH THE DAY. IN ADVANCE  
OF THE COLD FRONT, ADEQUATE MOISTURE AND OVERALL INSTABILITY WILL BE  
PRESENT TO SUPPORT AT LEAST SCATTERED THUNDERSTORMS. GIVEN THE  
PRESENCE OF MODEST VERTICAL WIND SHEAR, A FEW OF THE STORMS COULD  
BECOME STRONG TO LOCALLY SEVERE. THUNDERSTORMS MAY ALSO DEVELOP  
NORTH OF A SURFACE LOW ALONG THE CA/OR BORDER, AMID AN UNSTABLE  
AIRMASS SUPPORTIVE OF SCATTERED STRONG THUNDERSTORMS.  
   
..MIDWEST INTO THE OH VALLEY  
 
PRECEDING AN ADVANCING COLD FRONT, DIURNAL HEATING OF A MOIST  
BOUNDARY LAYER, ATOP RELATIVELY POOR MID-LEVEL LAPSE RATES, WILL  
RESULT IN AIRMASS DESTABILIZATION AND 1500-3000 J/KG SBCAPE BY  
AFTERNOON. WHILE MLCINH WILL MINIMIZE BY LATE MORNING, THE POOR  
MID-LEVEL LAPSE RATES SUGGEST THAT CAPE SHOULD BE CONSTRAINED TO  
TALL/THIN PROFILES. FURTHERMORE, UNIDIRECTIONAL VERTICAL WIND  
PROFILES WITH LITTLE STRENGTHENING WITH HEIGHT, SHOULD LEAD TO  
MEDIOCRE DEEP-LAYER SHEAR. WHILE MANY SCATTERED STORMS SHOULD  
DEVELOP ALONG THE COLD FRONT, AND AHEAD IN THE UNCAPPED WARM SECTOR,  
MOST STORMS SHOULD BE PULSE-CELLULAR TO MULTICELLULAR IN NATURE. A  
FEW OF THE STRONGER STORMS MAY SUPPORT WET DOWNBURSTS CAPABLE OF  
PRODUCING LOCALIZED DAMAGING GUSTS.  
   
..MID-ATLANTIC  
 
SIMILAR TO THE GREAT LAKES/OH VALLEY VICINITY, STRONG BOUNDARY-LAYER  
HEATING WILL QUICKLY REDUCE CONVECTIVE INHIBITION AND SUPPORT  
SCATTERED THUNDERSTORM DEVELOPMENT AMID WEAK VERTICAL WIND SHEAR.  
2000+ J/KG OF TALL/THIN SBCAPE WILL SUPPORT WET DOWNBURST POTENTIAL,  
AND A COUPLE OF DAMAGING WIND GUSTS ARE POSSIBLE.  
   
..SOUTHERN PLAINS  
 
SCATTERED THUNDERSTORMS SHOULD DEVELOP BY AFTERNOON PEAK HEATING  
AHEAD OF THE TRAILING COLD FRONT OVER THE SOUTHERN PLAINS. SURFACE  
TEMPERATURES SHOULD WARM TO NEAR 90 F AMID LOW TO MID 70S F  
DEWPOINTS, YIELDING AS MUCH AS 3000-4000 J/KG MLCAPE GIVEN MODEST  
MID-LEVEL LAPSE RATES. THOUGH VERTICAL WIND SHEAR SHOULD BE  
RELATIVELY POOR, THE STRONG BUOYANCY IN PLACE MAY COMPENSATE TO  
SUPPORT WET DOWNBURSTS AND ASSOCIATED ISOLATED SEVERE GUSTS WITH THE  
STRONGER STORMS.  
   
..NORTHERN CALIFORNIA INTO SOUTHERN OREGON  
 
SCATTERED THUNDERSTORMS WILL DEVELOP IMMEDIATELY NORTH OF A WEAK  
SURFACE LOW, WHERE LOCALIZED FORCING FOR ASCENT WILL BE IN PLACE.  
THESE THUNDERSTORMS SHOULD DEVELOP ATOP A MIXED BOUNDARY LAYER THAT  
MAY DEEPEN TO 600-500 MB. FURTHERMORE, THE PRESENCE OF 9+ C/KM LAPSE  
RATES THROUGH THE TROPOSPHERE MAY PROMOTE ENOUGH  
THERMODYNAMICALLY-DRIVEN DOWNWARD MOMENTUM TRANSPORT TO SUPPORT  
ISOLATED STRONG TO SEVERE WIND GUSTS. POINT FORECAST SOUNDINGS ALSO  
DEPICT CURVED/ELONGATED HODOGRAPHS, WHICH MAY SUPPORT MULTICELLS AND  
TRANSIENT SUPERCELLS WITH A MARGINAL HAIL THREAT.  
 
..SQUITIERI.. 06/29/2025  
 
 
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