Tornado Watch 812

Issued

Aug 27, 2011, 7:56 PM EDT (23:56 UTC)

Expired

Aug 28, 2011, 5:00 AM EDT

In force

9 hr

Issued by

the Storm Prediction Center

Largest hail expected

0.5 in

Strongest gust expected

60 kt

Two or more tornadoes

40%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

5%

One or more gusts of 65 knots or more

5%

Ten or more severe hail reports

5%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

20%

• Mesoscale Discussion 2068Aug 27, 4:44 PM EDT
• Mesoscale Discussion 2069Aug 27, 7:31 PM EDT
• Mesoscale Discussion 2071Aug 28, 12:30 AM EDT
• Mesoscale Discussion 2073Aug 28, 4:01 AM EDT

049 
WWUS20 KWNS 272359
SEL2
SPC WW 272359
CTZ000-DEZ000-NJZ000-NYZ000-CWZ000-280900-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 812
NWS STORM PREDICTION CENTER NORMAN OK
755 PM EDT SAT AUG 27 2011

THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

       SOUTHWESTERN CONNECTICUT
       SOUTHERN DELAWARE
       EASTERN NEW JERSEY
       FAR SOUTHEASTERN NEW YORK AND LONG ISLAND
       COASTAL WATERS

EFFECTIVE THIS SATURDAY NIGHT AND SUNDAY MORNING FROM 755 PM
UNTIL 500 AM EDT.

TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 50 STATUTE
MILES EAST AND WEST OF A LINE FROM 50 MILES SOUTH SOUTHEAST OF
DOVER DELAWARE TO 15 MILES EAST NORTHEAST OF BRIDGEPORT
CONNECTICUT.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU2).

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...THIS TORNADO WATCH REPLACES TORNADO
WATCH NUMBER 811. WATCH NUMBER 811 WILL NOT BE IN EFFECT AFTER
755 PM EDT.

DISCUSSION...HRCN IRENE EXPECTED TO CONTINUE SLOWLY NNEWD THROUGH
EARLY SUN.  SATELLITE AND THERMAL CONSIDERATIONS SUGGEST THAT THE
SYSTEM IS BEGINNING TO UNDERGO EXTRATROPICAL TRANSITION.  COUPLED
WITH THE FACT THAT THE CIRCULATION CENTER HAS NOW MOVED BACK OVER
OPEN WATER...ASSOCIATED WIND FIELD EXPECTED TO REMAIN AMPLY STRONG
TO SUPPORT LOW LVL ROTATION IN SEMI-DISCRETE SHOWERS/TSTMS FORMING
WITHIN AXIS OF WEAK SFC-BASED INSTABILITY ARCING NW FROM THE
ATLANTIC INTO THE NE QUADRANT OF THE SYSTEM.  THE GREATEST TORNADO
RISK IN THE NEAR TERM APPEARS TO BE ALONG THE SRN JERSEY SHORE AND
OVER LWR DE BAY.  THE THREAT SHOULD EDGE NWD INTO CNTRL NJ AND INTO
THE NYC AREA/SRN LONG ISLAND LATER TNGT.

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
400. MEAN STORM MOTION VECTOR 12040.


...CORFIDI

Tornado Watches in New Jersey, 2011Tornado Watches in New York, 2011Tornado Watches in Delaware, 2011Every tornado watch in 2011

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.