Severe Thunderstorm Watch 463

Issued

Jul 4, 2012, 6:10 PM EDT (22:10 UTC)

Expired

Jul 4, 2012, 9:49 PM EDT

In force

4 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

Counties Belknap County, NH, Carroll County, NH, Cheshire County, NH, Grafton County, NH, Hillsborough County, NH, Merrimack County, NH, Rockingham County, NH, Strafford County, NH, Sullivan County, NH, Clinton County, NY, Essex County, NY, Addison County, VT, Chittenden County, VT, Franklin County, VT, Grand Isle County, VT, Lamoille County, VT, Orange County, VT, Rutland County, VT, Washington County, VT, Windsor County, VT

The Burlington radar (KCXX), 72 km from the middle of the area, began a volume at 22:10 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Two or more tornadoes

10%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

40%

One or more gusts of 65 knots or more

5%

Ten or more severe hail reports

20%

One or more hailstones of 2 inches or more

5%

Six or more combined severe hail and wind reports

70%

• Mesoscale Discussion 1391Jul 4, 4:48 PM EDT

015 
WWUS20 KWNS 042212
SEL3
SPC WW 042212
MEZ000-NHZ000-NYZ000-VTZ000-CWZ000-050400-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 463
NWS STORM PREDICTION CENTER NORMAN OK
610 PM EDT WED JUL 4 2012

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

       WESTERN MAINE
       CENTRAL AND SOUTHERN NEW HAMPSHIRE
       NORTHEAST NEW YORK
       WESTERN AND CENTRAL VERMONT
       COASTAL WATERS

EFFECTIVE THIS WEDNESDAY NIGHT FROM 610 PM UNTIL MIDNIGHT 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 45
STATUTE MILES EAST AND WEST OF A LINE FROM 35 MILES NORTH OF
BURLINGTON VERMONT TO 25 MILES SOUTH SOUTHWEST OF PORTSMOUTH NEW
HAMPSHIRE.  FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU3).

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.

OTHER WATCH INFORMATION...CONTINUE...WW 460...WW 461...WW 462...

DISCUSSION...TSTMS...INCLUDING POSSIBLE SUSTAINED
STORMS/SUPERCELLS...EXPECTED TO CONTINUE FORMING IN NW-SE CORRIDOR
OF LOW LVL WAA/MOISTURE TRANSPORT AHEAD OF FAIRLY POTENT SRN QUEBEC
SHORTWAVE TROUGH.  COMBINATION OF SFC HEATING...AMPLY RICH LOW LVL
MOISTURE...AND 35-40 KT NWLY DEEP SHEAR MAY PROVE SUFFICIENT FOR
STORMS WITH SMALL BOWS/DMGG WIND...AND PERHAPS SVR HAIL...GIVEN
PRESENCE OF MODERATE LARGE SCALE FORCING FOR ASCENT.

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 32025.


...CORFIDI

Severe Thunderstorm Watches in New Hampshire, 2012Severe Thunderstorm Watches in Vermont, 2012Severe Thunderstorm Watches in New York, 2012Every severe thunderstorm watch in 2012

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; radar from the NEXRAD Level II archive.