Tornado Watch 178

Issued

Apr 20, 2009, 2:50 PM EDT (18:50 UTC)

Expired

Apr 20, 2009, 9:45 PM EDT

In force

7 hr

Issued by

the Storm Prediction Center

Largest hail expected

2 in

Strongest gust expected

60 kt

The Norfolk radar (KAKQ), 105 km from the middle of the area, began a volume at 18:49 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

40%

One or more EF2 to EF5 tornadoes

20%

Ten or more severe wind reports

50%

One or more gusts of 65 knots or more

30%

Ten or more severe hail reports

60%

One or more hailstones of 2 inches or more

30%

Six or more combined severe hail and wind reports

80%

• Mesoscale Discussion 536Apr 20, 12:22 PM EDT
• Mesoscale Discussion 537Apr 20, 2:09 PM EDT
• Mesoscale Discussion 539Apr 20, 4:55 PM EDT
• Mesoscale Discussion 540Apr 20, 4:57 PM EDT
• Mesoscale Discussion 541Apr 20, 7:15 PM EDT

869 
WWUS20 KWNS 201849
SEL8  
SPC WW 201849
MDZ000-NCZ000-VAZ000-CWZ000-210200-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 178
NWS STORM PREDICTION CENTER NORMAN OK
250 PM EDT MON APR 20 2009

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

       SOUTHEAST MARYLAND
       NORTHERN NORTH CAROLINA
       CENTRAL AND EASTERN VIRGINIA
       COASTAL WATERS

EFFECTIVE THIS MONDAY AFTERNOON AND EVENING FROM 250 PM UNTIL
1000 PM EDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.

THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 85 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 20 MILES WEST OF DANVILLE
VIRGINIA TO 50 MILES SOUTHEAST OF PATUXENT RIVER MARYLAND.  FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU8).

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.

DISCUSSION...THUNDERSTORMS ARE FORECAST TO INTENSIFY THIS AFTERNOON
OVER NORTHERN NC AND CENTRAL VA...AHEAD OF APPROACHING SURFACE LOW. 
ACTIVITY WILL SPREAD NORTHEASTWARD ACROSS THE WATCH AREA POSING A
RISK OF LARGE HAIL AND DAMAGING WINDS.  ENHANCED FORCING NEAR THE
WARM FRONT MAY ALSO POSE A RISK OF A FEW TORNADOES THIS AFTERNOON
AND EARLY EVENING.

AVIATION...TORNADOES AND 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
450. MEAN STORM MOTION VECTOR 24030.


...HART

Tornado Watches in Virginia, 2009Tornado Watches in North Carolina, 2009Tornado Watches in Maryland, 2009Every tornado watch in 2009

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.