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WWUS20 KWNS 171836

SEL6

SPC WW 171836

NYZ000-VTZ000-LOZ000-180400-



URGENT - IMMEDIATE BROADCAST REQUESTED

SEVERE THUNDERSTORM WATCH NUMBER 416

NWS STORM PREDICTION CENTER NORMAN OK

230 PM EDT WED JUL 17 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* SEVERE THUNDERSTORM WATCH FOR PORTIONS OF

  NORTHERN NEW YORK

  VERMONT

  LAKE ONTARIO



* EFFECTIVE THIS WEDNESDAY AFTERNOON FROM 230 PM UNTIL MIDNIGHT

  EDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH LIKELY



THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 55

STATUTE MILES NORTH AND SOUTH OF A LINE FROM 10 MILES SOUTHWEST

OF WATERTOWN NEW YORK TO 40 MILES SOUTHEAST OF NEWPORT VERMONT.

FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH

OUTLINE UPDATE (WOUS64 KWNS WOU6).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



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 NOW FORMING IN SRN ONT /N OF LK ONT/ EXPECTED TO

MOVE/DEVELOP GENERALLY ESE INTO PARTS OF UPSTATE NY AND VT AS

ASSOCIATED UPR IMPULSE CONTINUES ESEWD. GRADUALLY INCREASING DEEP

SHEAR AND STEEPENING LOW-LVL LAPSE RATES SHOULD SUPPORT SUFFICIENT

STRENGTHENING OF STORMS TO POSE A RISK FOR DMGG WIND AND POSSIBLY

MARGINALLY SVR HAIL IN WW AREA THROUGH LATE THIS AFTN/EARLY THIS

EVE.

UPSTREAM LINE OF STORMS NOW FORMING FARTHER N IN ON IS ASSOCIATED

WITH ANOTHER...STRONGER UPR IMPULSE NOW OVER WRN ONT. THIS LINE

SHOULD REMAIN STRONG TO SVR AS IT CONTINUES ESE INTO NRN NY/NRN NEW

ENGLAND THIS EVE. STRENGTHENING DEEP WNWLY WIND FIELD/ASCENT AHEAD

OF IMPULSE...AND UPLIFT ALONG STORM OUTFLOW BOUNDARIES...SUGGEST

POTENTIAL FOR SUSTAINED STORMS/EMBEDDED SUPERCELLS. ASSOCIATED

LEWPS AND BOW SEGMENTS MAY YIELD DMGG WIND AND POSSIBLY AN ISOLD

TORNADO INTO LATE EVE.



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 30025.





...CORFIDI

