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069 

WWUS20 KWNS 131740

SEL5

SPC WW 131740

CTZ000-MAZ000-NJZ000-NYZ000-PAZ000-140000-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 655

NWS STORM PREDICTION CENTER NORMAN OK

140 PM EDT MON SEP 13 2010



THE NWS STORM PREDICTION CENTER HAS ISSUED A

SEVERE THUNDERSTORM WATCH FOR PORTIONS OF



       WESTERN CONNECTICUT

       WESTERN MASSACHUSETTS

       NORTHERN NEW JERSEY

       SOUTHEAST NEW YORK

       NORTHEAST PENNSYLVANIA



EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 140 PM UNTIL 800

PM EDT.



HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 70

MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 60

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 25 MILES SOUTH

SOUTHWEST OF ITHACA NEW YORK TO 35 MILES SOUTH OF WESTFIELD

MASSACHUSETTS.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE

ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).



REMEMBER...A SEVERE THUNDERSTORM WATCH MEANS CONDITIONS ARE

FAVORABLE FOR SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH

AREA. PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR

THREATENING WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS

AND POSSIBLE WARNINGS. SEVERE THUNDERSTORMS CAN AND OCCASIONALLY

DO PRODUCE TORNADOES.



DISCUSSION...TSTMS CURRENTLY DEVELOPING NEAR BGM ARE EXPECTED TO

INCREASE IN COVERAGE AND INTENSITY THIS AFTERNOON IN ADVANCE OF

SHORT WAVE TROUGH AND ASSOCIATED 50-70 KT MIDLEVEL JET STREAK.

WHILE BOUNDARY LAYER IS NOT OVERLY HOT OR MOIST...THE PRESENCE OF

STEEP LOW TO MID-TROPOSPHERIC LAPSE RATES ARE CONTRIBUTING TO SBCAPE

APPROACHING 1000 J/KG.  WHEN COUPLED WITH THE STRENGTHENING DEEP

NWLY SHEAR...SETUP WILL FAVOR THE DEVELOPMENT OF ORGANIZED STORM

MODES INCLUDING SUPERCELLS AND BOWS WITH A RISK FOR DAMAGING WINDS

AND HAIL.



AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT

TO 1.5 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60

KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 500. MEAN STORM

MOTION VECTOR 29035.





...MEAD

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