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727 

WWUS20 KWNS 191959

SEL3

SPC WW 191959

NYZ000-PAZ000-200300-



URGENT - IMMEDIATE BROADCAST REQUESTED

TORNADO WATCH NUMBER 133

NWS STORM PREDICTION CENTER NORMAN OK

355 PM EDT FRI APR 19 2013



THE NWS STORM PREDICTION CENTER HAS ISSUED A



* TORNADO WATCH FOR PORTIONS OF

  SOUTHEAST NEW YORK

  CENTRAL AND EASTERN PENNSYLVANIA



* EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 355 PM UNTIL

  1100 PM EDT.



* PRIMARY THREATS INCLUDE...

  SEVERAL TORNADOES POSSIBLE

  SEVERAL DAMAGING WIND GUSTS TO 70 MPH POSSIBLE



THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 70 STATUTE

MILES EAST AND WEST OF A LINE FROM 35 MILES SOUTH SOUTHWEST OF

HARRISBURG PENNSYLVANIA TO 50 MILES NORTH NORTHWEST OF

WILKESBARRE PENNSYLVANIA.  FOR A COMPLETE DEPICTION OF THE WATCH

SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).



PRECAUTIONARY/PREPAREDNESS ACTIONS...



REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR

TORNADOES AND 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.



&&



OTHER WATCH INFORMATION...CONTINUE...WW 129...WW 130...WW

131...WW 132...



DISCUSSION...A STRONGLY FORCED CONVECTIVE BAND WITH EMBEDDED TSTMS

IS CURRENTLY EVOLVING ALONG THE SYNOPTIC COLD FRONT OVER CNTRL PA.

THE DOWNSTREAM AIR MASS ACROSS ERN PA SHOULD CONTINUE TO

WARM/MOISTEN LATE THIS AFTERNOON WITH MLCAPE VALUES RISING TO

250-500 J/KG.  WHEN COUPLED WITH INTENSIFYING DEEP-LAYER

ASCENT...EXPECT FURTHER STRENGTHENING OF THE CONVECTIVE BAND AMIDST

A STRONGLY SHEARED ENVIRONMENT.  AS SUCH...THE POTENTIAL WILL EXIST

FOR EMBEDDED SUPERCELL AND/OR LEWP STRUCTURES CAPABLE OF DAMAGING

WINDS AND MESO-VORTICES/TORNADOES.



AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL

SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE

WIND GUSTS TO 60 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO

350. MEAN STORM MOTION VECTOR 23045.





...MEAD

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