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 
