Severe Thunderstorm Watch 481

Issued

Jul 8, 2012, 1:44 PM EDT (17:44 UTC)

Expired

Jul 8, 2012, 10:00 PM EDT

In force

8 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Sterling radar (KLWX), 177 km from the middle of the area, began a volume at 17:45 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

20%

One or more EF2 to EF5 tornadoes

2%

Ten or more severe wind reports

80%

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

90%

• Mesoscale Discussion 1433Jul 8, 12:47 PM EDT
• Mesoscale Discussion 1435Jul 8, 1:29 PM EDT
• Mesoscale Discussion 1436Jul 8, 4:21 PM EDT
• Mesoscale Discussion 1438Jul 8, 6:00 PM EDT
• Mesoscale Discussion 1440Jul 8, 7:08 PM EDT

176 
WWUS20 KWNS 081748
SEL1
SPC WW 081748
DCZ000-DEZ000-KYZ000-MDZ000-OHZ000-VAZ000-WVZ000-CWZ000-090200-

URGENT - IMMEDIATE BROADCAST REQUESTED
SEVERE THUNDERSTORM WATCH NUMBER 481
NWS STORM PREDICTION CENTER NORMAN OK
145 PM EDT SUN JUL 8 2012

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

       DISTRICT OF COLUMBIA
       DELAWARE
       EXTREME NORTHEAST KENTUCKY
       MARYLAND
       EXTREME SOUTHEAST OHIO
       NORTHERN AND CENTRAL VIRGINIA
       WEST VIRGINIA
       COASTAL WATERS

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 145 PM UNTIL
1000 PM EDT.

HAIL TO 2 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 60
STATUTE MILES EITHER SIDE OF A LINE FROM 45 MILES WEST SOUTHWEST
OF CHARLESTON WEST VIRGINIA TO 35 MILES NORTHEAST OF SALISBURY
MARYLAND.  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.

DISCUSSION...STORMS ARE DEVELOPING ALONG A COLD FRONT FROM SERN OH
INTO NRN MD AS IT MOVES SEWD INTO A MOIST AND VERY UNSTABLE
ENVIRONMENT.  TEMPERATURES ARE IN THE MID 90S TO AROUND 100F AHEAD
OF THE FRONT RESULTING IN STEEP LOW LEVEL LAPSE RATES WHICH WILL
ENHANCE THREAT FOR DAMAGING WIND GUSTS.  IN ADDITION...LARGE
INSTABILITY INDICATES POTENTIAL FOR STORMS TO PRODUCE LARGE HAIL.
ACTIVITY IS EXPECTED TO CONTINUING DEVELOPING AND MOVE ESEWD THIS
AFTERNOON INTO THE EVENING.

AVIATION...A FEW SEVERE THUNDERSTORMS WITH HAIL SURFACE AND ALOFT
TO 2 INCHES. EXTREME TURBULENCE AND SURFACE WIND GUSTS TO 60
KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 550. MEAN STORM
MOTION VECTOR 28020.


...WEISS

Severe Thunderstorm Watches in Virginia, 2012Severe Thunderstorm Watches in West Virginia, 2012Severe Thunderstorm Watches in Maryland, 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.