SPC - No watches are valid as of Mon Jul 28 13:45:01 UTC 2014

No watches are valid as of Mon Jul 28 13:45:01 UTC 2014.

SPC Jul 28, 2014 1300 UTC Day 1 Convective Outlook

SPC 1300Z Day 1 Outlook
      
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK
0725 AM CDT MON JUL 28 2014

VALID 281300Z - 291200Z

...THERE IS A SLGT RISK OF SVR TSTMS THIS AFTERNOON/EVENING FROM THE
COASTAL CAROLINAS TO THE N CENTRAL GULF COAST...

...SUMMARY...
A FEW STRONG TO SEVERE STORMS CAPABLE OF PRODUCING DAMAGING WINDS
WILL BE POSSIBLE THIS AFTERNOON AND EVENING FROM THE COASTAL
CAROLINAS EXTENDING WEST SOUTHWESTWARD INTO THE NORTH CENTRAL GULF
COAST STATES.  ISOLATED STRONG TO SEVERE STORMS MAY ALSO OCCUR TODAY
OVER PORTIONS OF NEW ENGLAND.

...COASTAL CAROLINAS TO THE N CENTRAL GULF COAST THIS AFTERNOON...
A SURFACE COLD FRONT WILL REACH THE NC COAST BY ABOUT MID
AFTERNOON...AND WILL CONTINUE SWD TO THE I-10 CORRIDOR ALONG THE
GULF COAST TONIGHT.  LOW-LEVEL ASCENT ALONG THE FRONT...POTENTIALLY
AUGMENTED BY LOCAL SEA BREEZE CIRCULATIONS...WILL SUPPORT SCATTERED
THUNDERSTORM DEVELOPMENT IN A BROKEN BAND ALONG THE FRONT THIS
AFTERNOON/EVENING.  MODERATE-STRONG BUOYANCY IS EXPECTED IN ADVANCE
OF THE FRONT...WHILE DEEP-LAYER FLOW AND VERTICAL SHEAR WILL WEAKEN
QUICKLY WITH SWD EXTENT FROM NC.  FORECAST SOUNDINGS SHOW THE
POTENTIAL FOR DAMAGING OUTFLOW WINDS WITH DOWNBURSTS...GIVEN BOTH
LARGE BUOYANCY AND HIGH PW VALUES TO SUPPORT PRECIPITATION
LOADING...AND LARGE DCAPE FOR STRONG RAIN-COOLED DOWNDRAFTS.  THE
GREATER RISK FOR MORE ORGANIZED STORM CLUSTERS AND DOWNWARD MOMENTUM
TRANSFER WILL BE ACROSS COASTAL NC WHERE MIDLEVEL FLOW WILL APPROACH
50 KT.  

...NEW ENGLAND TODAY...
INITIAL CLUSTERS OF THUNDERSTORMS WILL SPREAD NWD/NEWD OVER NEW
ENGLAND THIS MORNING IN ASSOCIATION WITH LOW-LEVEL WAA AND A LEAD
SHORTWAVE TROUGH.  THOUGH BUOYANCY IS LIMITED...VERTICAL SHEAR AND
MOIST PROFILES COULD SUPPORT WEAKLY ROTATING STORMS THIS MORNING. 
BY THIS AFTERNOON...THE PRIMARY SHORTWAVE TROUGH WILL PIVOT EWD OVER
PA/NY...AS THE ASSOCIATED SURFACE CYCLONE DEVELOPS SLOWLY NEWD FROM
NY TO NRN NEW ENGLAND...AND A TRAILING COLD FRONT LIKEWISE
PROGRESSES EWD.  ADDITIONAL BANDS OF THUNDERSTORMS SHOULD DEVELOP BY
EARLY AFTERNOON NEAR THE SURFACE LOW AND COLD FRONT WHERE ASCENT
WILL BE FOCUSED.  A FEW CLOUD BREAKS WILL BE POSSIBLE ON THE EDGE OF
THE MIDLEVEL DRY SLOT...SUCH THAT SOME SURFACE HEATING COULD BOOST
MLCAPE TO 750-1500 J/KG.  MEANWHILE...VERTICAL SHEAR WILL BE AT
LEAST MARGINALLY FAVORABLE FOR ORGANIZED STORMS/SUPERCELLS WITH
EFFECTIVE BULK SHEAR OF 30-40 KT.  SINCE THE STRONGER LOW-LEVEL
SHEAR WILL REMAIN REMOVED TO THE N OF THE STRONGER BUOYANCY AND
LAPSE RATES WILL NOT BE STEEP...THE OVERALL SEVERE STORM RISK SHOULD
REMAIN MARGINAL.

..THOMPSON/BOTHWELL.. 07/28/2014


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