The Storm Prediction Center is highlighting Southern New England for an isolated severe weather threat on Tuesday afternoon and early evening. It is unlikely that they will issue a Severe Thunderstorm Watch, but conditions are somewhat favorable for isolated strong thunderstorms to develop in Southern New England. A disturbance approaching from the west will encounter very warm and muggy air over Southern New England. Thunderstorms will likely develop, and some of them could become strong/severe. The threat diminishes after sunset.
The following is at technical discussion from the Storm Prediction Center regarding the severe weather potential in Southern New England.
MESOSCALE DISCUSSION 1481 NWS STORM PREDICTION CENTER NORMAN OK 0158 PM CDT TUE JUL 23 2013 AREAS AFFECTED...NRN NJ...SERN NY AND LONG ISLAND...MA...CT...RI CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY VALID 231858Z - 232000Z PROBABILITY OF WATCH ISSUANCE...20 PERCENT SUMMARY...THUNDERSTORM CLUSTERS WILL CONTINUE SPREADING EWD THIS AFTERNOON ACROSS NRN NJ...SERN NY/LONG ISLAND...MA...CT...AND RI. ISOLATED DAMAGING WIND GUSTS AND SMALL HAIL MAY ACCOMPANY A FEW OF THE STRONGER STORMS...BUT THE SEVERE WEATHER THREAT DOES NOT APPEAR TO WARRANT A WW. DISCUSSION...WEAK AREA OF SURFACE LOW PRESSURE ASSOCIATED WITH A LOW AMPLITUDE UPPER TROUGH WAS ANALYZED EARLY THIS AFTERNOON DRIFTING ENEWD ACROSS SRN NEW ENGLAND...WITH A SURFACE PRESSURE TROUGH EXTENDING SWWD INTO THE MID-ATLANTIC REGION. CLEARING SKIES DURING THE PAST FEW HOURS HAVE AIDED IN BOOSTING SURFACE TEMPERATURES INTO THE MID 70S TO MID 80S AMIDST A MOIST AIRMASS WITH DEWPOINTS IN THE LOW 70S. AS A RESULT...MLCAPE VALUES HAVE INCREASED TO 500-1500 J/KG ACROSS THE AREA...WHICH HAS AIDED IN THE DEVELOPMENT OF THUNDERSTORM CLUSTERS. AT 1845Z...ONE BAND OF STORMS WAS MOVING E OFF OF THE APPALACHIANS AND INTO SERN NY/NRN NJ...WHILE A SECOND BAND ORIENTED W-E WAS LOCATED OVER CT/MA. DEEP-LAYER FLOW IS GENERALLY OUT OF THE WSW...WITH SPEEDS INCREASING FROM 30 KT AT 6 KM AGL TO 60 KT AT 12 KM AGL...PER AREA VWP/S AND RAP FORECAST SOUNDINGS. THIS WIND PROFILE COMBINED WITH WEAK TO MODERATE INSTABILITY WILL SUPPORT ISOLATED STRONG TO SEVERE MULTICELL CLUSTERS POSING A THREAT FOR DAMAGING WINDS AND SMALL HAIL. THREAT WILL LIKELY WANE AS THE BOUNDARY LAYER COOLS THIS EVENING AND THE UPPER TROUGH EXITS THE REGION. ..GARNER/KERR.. 07/23/2013