THE NWS STORM PREDICTION CENTER HAS ISSUED A SEVERE THUNDERSTORM WATCH FOR PORTIONS OF CONNECTICUT DISTRICT OF COLUMBIA DELAWARE MARYLAND NEW JERSEY SOUTHEAST NEW YORK EASTERN PENNSYLVANIA NORTHERN AND CENTRAL VIRGINIA COASTAL WATERS EFFECTIVE THIS FRIDAY AFTERNOON AND EVENING FROM 155 PM UNTIL 900 PM EDT. HAIL TO 1.5 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS TO 65 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS. THE SEVERE THUNDERSTORM WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE MILES EAST AND WEST OF A LINE FROM 40 MILES NORTH NORTHEAST OF POUGHKEEPSIE NEW YORK TO 35 MILES SOUTH SOUTHEAST OF WASHINGTON DISTRICT OF COLUMBIA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU0). 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...CLUSTERS OF THUNDERSTORMS ARE EXPECTED TO CONTINUE DEVELOPING AND INTENSIFY THIS AFTERNOON IN ADVANCE OF A SHORT WAVE TROUGH MOVING EWD TOWARD THE MID ATLANTIC REGION. AIR MASS IS VERY MOIST WITH SURFACE DEW POINTS IN THE LOW 70S...AND DIABATIC HEATING HAS RESULTED IN DESTABILIZATION WITH MLCAPE OF 1500 J/KG. SWLY MID LEVEL WINDS OF 30-40 KT ARE CONTRIBUTING TO SUFFICIENT VERTICAL SHEAR TO ENHANCE THREAT FOR SEVERE STORMS. LOCALIZED DAMAGING WIND GUSTS AND HAIL WILL BE THE PRIMARY THREATS.
Tornadoes
Probability of 2 or more tornadoes |
Low (10%)
|
Probability of 1 or more strong (F2-F5) tornadoes |
Low (5%)
|
Probability of 10 or more severe wind events |
Mod (40%)
|
Probability of 1 or more wind events > 65 knots |
Low (10%)
|
Probability of 10 or more severe hail events |
Low (20%)
|
Probability of 1 or more hailstones > 2 inches |
Low (<5%)
|
Probability of 6 or more combined severe hail/wind events |
High (70%)
|