000
ACUS11 KWNS 280825
SWOMCD
SPC MCD 280824
RIZ000-CTZ000-NYZ000-281030-

MESOSCALE DISCUSSION 1496
NWS STORM PREDICTION CENTER NORMAN OK
0324 AM CDT MON JUL 28 2014

AREAS AFFECTED...CENTRAL AND ERN LONG ISLAND...AND COASTAL AREAS OF
SERN CT/SRN RI

CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY

VALID 280824Z - 281030Z

PROBABILITY OF WATCH ISSUANCE...20 PERCENT

SUMMARY...A FEW STRONGER WIND GUSTS /MAINLY LESS THAN 50 KT/ WILL BE
POSSIBLE THROUGH THE OVERNIGHT TO EARLY MORNING AS THE NRN EXTENT OF
A LINE OF STORMS MOVES ACROSS CENTRAL AND ERN LONG ISLAND...AND
PERHAPS IN VICINITY OF THE COAST OF SERN CT AND RI.  LOW SEVERE
PROBABILITY PRECLUDES THE NEED FOR A SEVERE TSTM WATCH.

DISCUSSION...TRENDS IN OVERNIGHT MOSAIC RADAR IMAGERY SHOWED A LINE
OF TSTMS HAD MOVED OFF THE NJ COAST...AND WAS TRACKING ENEWD AT
30-35 KT ACROSS WRN INTO CENTRAL LONG ISLAND...WITH THE SRN EXTENT
OF THIS LINE OVER THE ATLANTIC WATERS /60 E ACY/.  SURFACE DEW
POINTS BEING MAINTAINED IN THE LOWER 70S ARE HELPING TO OFFSET
SOMEWHAT THE BOUNDARY LAYER STABILIZATION.  HOWEVER...TIME OF DAY
AND THE PRESENCE OF WEAK MIDLEVEL LAPSE RATES ARE RESULTING IN
GENERALLY WEAK INSTABILITY.  STRENGTHENING MID-UPPER LEVEL WINDS
FROM DELMARVA TO SRN NEW ENGLAND WITH THE APPROACH OF THE UPPER OH
VALLEY/LOWER GREAT LAKES CLOSED LOW/SHORTWAVE TROUGH IS RESULTING IN
INCREASING DEEP LAYER SHEAR EARLY THIS MORNING ACROSS THE DISCUSSION
AREA.  WSR-88D VAD AT OKX SHOWED VEERING WINDS WITH HEIGHT IN THE
LOWEST 0.25-0.5 KM ARL...AND BACKING WINDS BETWEEN 0.5 KM TO AROUND
1 KM ARL.

HEIGHT FALLS WITH THE APPROACH OF THE UPPER OH VALLEY/LOWER GREAT
LAKES CLOSED LOW/TROUGH AND INCREASING DIFFLUENT FLOW ALOFT WILL
SUPPORT ADDITIONAL TSTM DEVELOPMENT ACROSS LONG ISLAND INTO SRN NEW
ENGLAND...AND MAINTAIN SOME STORM ORGANIZATION.  THE OVERALL SEVERE
WEATHER THREAT SHOULD REMAIN LOW...GIVEN THE WEAK INSTABILITY AND
MARGINAL LOW-LEVEL SHEAR.

..PETERS/THOMPSON.. 07/28/2014

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

ATTN...WFO...BOX...OKX...

LAT...LON   40777310 40967298 41237273 41417154 41447121 41077084
            40507110 40277225 40327299 40777310