Alert archive / Virginia / Tornado Watches in 2003

Tornado Watch 340

May 10, 200317 counties in North Carolina; 24 counties in Virginia

The Storm Prediction Center issued this tornado watch at May 10, 2003, 3:15 PM EDT for 17 counties in North Carolina; 24 counties in Virginia. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
May 10, 2003, 3:15 PM EDT (19:15 UTC)
Expired
May 10, 2003, 9:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
All 41 counties

Alamance County, NC, Caswell County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Granville County, NC, Guilford County, NC, Halifax County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Person County, NC, Rockingham County, NC, Stokes County, NC, Vance County, NC, Warren County, NC, Wilson County, NC, Bedford County, VA, Brunswick County, VA, Campbell County, VA, Charlotte County, VA, City of Danville, VA, City of Emporia, VA, City of Martinsville, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Dinwiddie County, VA, Floyd County, VA, Franklin County, VA, Greensville County, VA, Halifax County, VA, Henry County, VA, Lunenburg County, VA, Mecklenburg County, VA, Montgomery County, VA, Nottoway County, VA, Patrick County, VA, Pittsylvania County, VA, Prince Edward County, VA, Roanoke County, VA

The radar

The Roanoke radar (KFCX), 96 km from the middle of the area, began a volume at 19:15 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.

Warnings issued inside it

18 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
May 10, 4:01 PM EDTSevere Thunderstorm WarningRNKPittsylvania44 min
May 10, 4:08 PM EDTSevere Thunderstorm WarningRNKCharlotte, Halifax37 min
May 10, 4:12 PM EDTSevere Thunderstorm WarningRNKHalifax33 min
May 10, 4:42 PM EDTSevere Thunderstorm WarningRNKHalifax48 min
May 10, 4:50 PM EDTSevere Thunderstorm WarningRAHGranville, Vance40 min
May 10, 5:11 PM EDTSevere Thunderstorm WarningRNKBedford49 min
May 10, 5:29 PM EDTTornado WarningRAHVance46 min
May 10, 5:43 PM EDTSevere Thunderstorm WarningRNKCampbell, City of Lynchburg32 min
May 10, 5:49 PM EDTSevere Thunderstorm WarningRAHWarren56 min
May 10, 6:06 PM EDTSevere Thunderstorm WarningRNKHalifax39 min
May 10, 6:15 PM EDTSevere Thunderstorm WarningAKQMecklenburg40 min
May 10, 6:31 PM EDTSevere Thunderstorm WarningRAHGranville, Vance29 min
May 10, 6:37 PM EDTSevere Thunderstorm WarningRAHHalifax, Nash53 min
May 10, 6:45 PM EDTSevere Thunderstorm WarningRAHPerson30 min
May 10, 6:58 PM EDTSevere Thunderstorm WarningRAHVance32 min
May 10, 7:08 PM EDTSevere Thunderstorm WarningRAHEdgecombe, Halifax67 min
May 10, 7:17 PM EDTSevere Thunderstorm WarningRAHGranville43 min
May 10, 7:24 PM EDTSevere Thunderstorm WarningRAHWarren36 min

Discussions around it

SPC mesoscale discussions over the same counties from four hours before the watch to its end.

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 7.3 hours before the alert went out and 49 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Roanoke, VA at 12:00Z on 2003-05-10Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1311 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 12:00Z on 2003-05-10The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 91 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1311 J/kg
Mixed-layer CIN
-14 J/kg
Mixed-layer LCL
674 m above ground
0-6 km bulk shear
58 kt
0-1 km storm-relative helicity
91 m²/s²
0-3 km storm-relative helicity
115 m²/s²
Significant tornado parameter
0.7
Supercell composite
2.5

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000 
WWUS20 KWNS 101912
SEL0  
SPC WW 101915
NCZ000-VAZ000-110100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 340 
NWS STORM PREDICTION CENTER NORMAN OK 
315 PM EDT SAT MAY 10 2003

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

       NORTHERN NORTH CAROLINA
       SOUTHERN VIRGINIA

EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 315 PM UNTIL
900 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 ALONG AND 50 STATUTE MILES NORTH AND
SOUTH OF A LINE FROM 40 MILES SOUTHWEST OF ROANOKE VIRGINIA TO 45
MILES NORTHEAST OF ROCKY MOUNT NORTH CAROLINA.

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...CONTINUE...WW 336...WW 337...WW 338...WW
339...


DISCUSSION...ISOLATED THUNDERSTORMS ARE FORMING OVER THE MOUNTAINS
OF SOUTHWEST VA...AND MAY DEVELOP OVER NORTH CENTRAL NC SOON.  VERY
MOIST/UNSTABLE AIRMASS...STRONG WINDS ALOFT...AND ENHANCED SHEAR
NEAR SURFACE BOUNDARY MAY PROMOTE THE THREAT OF SUPERCELLS. 
ISOLATED TORNADOES MAY OCCUR WITH STORMS NEAR THE BOUNDARY.

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 500.
MEAN STORM MOTION VECTOR 26030.


...HART

373,0802 370,0771 353,0771 361,0802

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 9, 9:45 PM EDTMesoscale DiscussionSPCCarteret, Craven, Duplin, Greene, Jones, Lenoir and 3 more60 min
May 10, 12:41 PM EDTMesoscale DiscussionSPCAlleghany, Ashe, Avery, Mitchell, Rockingham, Stokes and 4 more2 hr
May 10, 2:31 PM EDTMesoscale DiscussionSPCAlamance, Beaufort, Bertie, Caswell, Chowan, Durham and 19 more89 min
May 10, 4:46 PM EDTMesoscale DiscussionSPCAlamance, Caswell, Durham, Edgecombe, Franklin, Granville and 11 more89 min
May 10, 7:10 PM EDTTornado WatchSPCBeaufort, Bertie, Camden, Chowan, Currituck, Dare and 20 more6 hr
May 9, 8:57 PM EDTMesoscale DiscussionSPCAlleghany, Bath, Botetourt, Craig, Rockbridge, City of Buena Vista and 2 more63 min
May 10, 4:33 AM EDTMesoscale DiscussionSPCAlleghany, Bath, Frederick, Highland, Rockingham, Shenandoah and 3 more87 min
May 10, 1:20 PM EDTTornado WatchSPCBland, Buchanan, Carroll, Dickenson, Giles, Grayson and 13 more6 hr
May 10, 3:27 PM EDTMesoscale DiscussionSPCBland, Buchanan, Carroll, Dickenson, Giles, Grayson and 13 more93 min
May 10, 6:30 PM EDTTornado WatchSPCGiles6 hr

Nearby

Tornado Watches in Virginia, 2003Tornado Watches in North Carolina, 2003Every tornado watch in 2003

Sources

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.