Severe Thunderstorm Watch 461

Issued

Jul 4, 2012, 4:26 PM EDT (20:26 UTC)

Expired

Jul 4, 2012, 9:59 PM EDT

In force

6 hr

Issued by

the Storm Prediction Center

Largest hail expected

1.5 in

Strongest gust expected

60 kt

The Pittsburgh radar (KPBZ), 110 km from the middle of the area, began a volume at 20:26 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

5%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

30%

One or more gusts of 65 knots or more

20%

Ten or more severe hail reports

30%

One or more hailstones of 2 inches or more

20%

Six or more combined severe hail and wind reports

60%

• Mesoscale Discussion 1390Jul 4, 4:04 PM EDT
• Mesoscale Discussion 1396Jul 4, 8:05 PM EDT
• Mesoscale Discussion 1397Jul 4, 9:48 PM EDT

508 
WWUS20 KWNS 042028
SEL1
SPC WW 042028
MDZ000-OHZ000-PAZ000-WVZ000-050200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 461
NWS STORM PREDICTION CENTER NORMAN OK
425 PM EDT WED JUL 4 2012

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

       EXTREME WESTERN MARYLAND PANHANDLE
       SOUTHEAST OHIO
       SOUTHWEST PENNSYLVANIA
       NORTHERN WEST VIRGINIA

EFFECTIVE THIS WEDNESDAY AFTERNOON AND EVENING FROM 425 PM UNTIL
1000 PM 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 NORTH AND SOUTH OF A LINE FROM 15 MILES NORTHWEST
OF PARKERSBURG WEST VIRGINIA TO 30 MILES EAST SOUTHEAST OF
MORGANTOWN WEST VIRGINIA.  FOR A COMPLETE DEPICTION OF THE WATCH
SEE THE ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU1).

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...

DISCUSSION...INITIAL STORMS INVOF THE WV PANHANDLE/SE OH COULD
INCREASE SOME IN COVERAGE/INTENSITY AS DAYTIME HEATING
PERSISTS...AND STORM MERGERS/INTERACTIONS COULD EVENTUALLY LEAD TO
THE FORMATION OF A SMALL CLUSTER OF STORMS.  THE THERMODYNAMIC
ENVIRONMENT IS FAVORABLE FOR ISOLATED LARGE HAIL GIVEN MLCAPE NEAR
2500 J/KG AND A FEW DAMAGING DOWNBURSTS BASED ON STEEP LOW-LEVEL
LAPSE RATES AND LARGE DCAPE.  OVER THE NEXT FEW HOURS...STORMS
SHOULD SPREAD SWD/SEWD TOWARD WV GIVEN 20-30 KT NNWLY MIDLEVEL FLOW.

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 33020.


...THOMPSON

Severe Thunderstorm Watches in West Virginia, 2012Severe Thunderstorm Watches in Ohio, 2012Severe Thunderstorm Watches in Pennsylvania, 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.