

271 

ACUS11 KWNS 091726

SWOMCD

SPC MCD 091725

MAZ000-NHZ000-RIZ000-CTZ000-NYZ000-091930-



MESOSCALE DISCUSSION 1678

NWS STORM PREDICTION CENTER NORMAN OK

1225 PM CDT FRI AUG 09 2013



AREAS AFFECTED...PART OF SERN NY/CT/MA/NRN RI/FAR SRN NH



CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY



VALID 091725Z - 091930Z



PROBABILITY OF WATCH ISSUANCE...20 PERCENT



SUMMARY...TSTMS MOVING ENEWD ACROSS SRN NEW ENGLAND THIS AFTERNOON

WILL POSE A THREAT FOR WET MICROBURSTS...A FEW POTENTIALLY PRODUCING

DAMAGING WIND GUSTS...WHILE A NONZERO THREAT EXISTS FOR A

FUNNEL/BRIEF...WEAK TORNADO.  GIVEN THE LOW SEVERE WEATHER

THREAT...A WATCH ISSUANCE IS NOT WARRANTED...THOUGH CONVECTIVE

TRENDS WILL BE MONITORED.



DISCUSSION...SINCE 16Z...REGIONAL RADAR IMAGERY OVER SERN NY INTO

WRN/NRN CT AND PARTS OF CENTRAL MA HAVE INDICATED RELATIVELY BROAD

LOW-MID LEVEL ROTATION COUPLETS WITH A BAND OF TSTMS EMBEDDED IN A

LARGER CLOUD/PRECIPITATION SHIELD ACROSS SRN NEW ENGLAND.  THESE

STORMS APPEAR TO BE ATTENDANT TO A PROGRESSIVE MIDLEVEL IMPULSE

MOVING ACROSS SERN NY/CT ATTM AND FURTHER AIDED BY LARGE SCALE

ASCENT AHEAD OF THE UPSTREAM TROUGH TRACKING THROUGH THE LOWER GREAT

LAKES STATES.  ALTHOUGH THE EXTENSIVE CLOUDINESS AND WEAK LAPSE

RATES WILL LIMIT STRONGER DESTABILIZATION TODAY...STRONG EFFECTIVE

BULK SHEAR TO AROUND 40 KT WILL SUPPORT ORGANIZATION AS INDICATED BY

THE ONGOING UPDRAFT ROTATION.  VERTICALLY VEERING WIND PROFILES PER

AREA WSR-88D VADS AT OKX/BOX SHOWED LOW LEVEL HODOGRAPH

CURVATURE/LOW LEVEL SHEAR SUFFICIENT FOR A TORNADO THREAT.  THE WEAK

INSTABILITY IS EXPECTED TO LIMIT STORM INTENSITIES...THOUGH

AFOREMENTIONED KINEMATICS AND A VERY MOIST AIR MASS /PW AROUND 2

INCH/ SUGGEST WET MICROBURSTS WILL BE POSSIBLE AND A BRIEF/WEAK

TORNADO CANNOT BE RULED OUT.



..PETERS/WEISS.. 08/09/2013



...PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT...



ATTN...WFO...GYX...BOX...OKX...ALY...



LAT...LON   41607415 42157315 42717241 42777122 42417122 42047124

            41747144 41647184 41547229 41457285 41387345 41407400

            41607415

