Alert archive / Virginia / Tornado Watches in 2011
Tornado Watch 41
The Storm Prediction Center issued this tornado watch at Mar 6, 2011, 6:24 PM EST for 20 counties in North Carolina; 29 counties in Virginia. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- Mar 6, 2011, 6:24 PM EST (23:24 UTC)
- Expired
- Mar 6, 2011, 10:20 PM EST
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 0.5 in
- Strongest gust expected
- 55 kt
All 49 counties
Beaufort County, NC, Bertie County, NC, Camden County, NC, Chowan County, NC, Currituck County, NC, Edgecombe County, NC, Gates County, NC, Greene County, NC, Halifax County, NC, Hertford County, NC, Lenoir County, NC, Martin County, NC, Nash County, NC, Northampton County, NC, Pasquotank County, NC, Perquimans County, NC, Pitt County, NC, Washington County, NC, Wayne County, NC, Wilson County, NC, Charles City County, VA, Chesterfield County, VA, City of Chesapeake, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Richmond, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Dinwiddie County, VA, Gloucester County, VA, Greensville County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, Mathews County, VA, New Kent County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, York County, VA
The radar
The Norfolk radar (KAKQ), 42 km from the middle of the area, began a volume at 23:27 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.
What SPC expected
The probabilities SPC published with the watch, for the watch area over its life.
- Two or more tornadoes
- 30%
- One or more EF2 to EF5 tornadoes
- 10%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 10%
- Ten or more severe hail reports
- 5%
- One or more hailstones of 2 inches or more
- 5%
- Six or more combined severe hail and wind reports
- 50%
Warnings issued inside it
1 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 6, 7:27 PM EST | Severe Thunderstorm Warning | AKQ | Charles City, Chesterfield, Hanover, Henrico, King and Queen, King William and 1 more | 48 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
Newport, NC (KMHX), launched 12:00Z, 11.4 hours before the alert went out and 207 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.
- Mixed-layer CAPE
- 54 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 562 m above ground
- 0-6 km bulk shear
- 37 kt
- 0-1 km storm-relative helicity
- 159 m²/s²
- 0-3 km storm-relative helicity
- 241 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted, in the capitals the NWS used until 2016.
461
WWUS20 KWNS 062327
SEL1
SPC WW 062327
NCZ000-VAZ000-CWZ000-070400-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 41
NWS STORM PREDICTION CENTER NORMAN OK
625 PM EST SUN MAR 6 2011
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
EASTERN NORTH CAROLINA
SOUTHEASTERN VIRGINIA
COASTAL WATERS
EFFECTIVE THIS SUNDAY EVENING FROM 625 PM UNTIL 1100 PM EST.
TORNADOES...HAIL TO 0.5 INCH IN DIAMETER...THUNDERSTORM WIND
GUSTS TO 65 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE
AREAS.
THE TORNADO WATCH AREA IS APPROXIMATELY ALONG AND 55 STATUTE
MILES EAST AND WEST OF A LINE FROM 50 MILES NORTHWEST OF NORFOLK
VIRGINIA TO 50 MILES EAST OF GOLDSBORO NORTH CAROLINA. FOR A
COMPLETE DEPICTION OF THE WATCH SEE THE ASSOCIATED WATCH OUTLINE
UPDATE (WOUS64 KWNS WOU1).
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...LOW-TOPPED CONVECTIVE BAND HAS FORMED ALONG A LOW-LVL
CONFLUENCE ZONE OVER ERN NC/SE VA THIS EVE...ON LEADING EDGE OF
MID-LVL HEIGHT FALLS/COLD ADVECTION ASSOCIATED WITH EJECTING UPR
VORT. STRENGTH OF LOW-LVL WIND FIELD AND WEAK LINEAR FORCING IN SRN
PART OF CONVECTIVE BAND SUGGEST POTENTIAL FOR LOW-LVL MESOS/ISOLD
TORNADOES IN E CNTRL/NE NC. FARTHER N...LOW-LVL LINEAR FORCING WILL
INCREASE THIS EVE AS SFC COLD FRONT OVERTAKES CONVECTIVE BAND. THIS
SUGGESTS A GREATER POTENTIAL FOR LEWPS WITH LOCALLY DMGG WIND IN NRN
PART OF WW.
AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 0.5 INCH. EXTREME TURBULENCE AND SURFACE
WIND GUSTS TO 55 KNOTS. A FEW CUMULONIMBI WITH MAXIMUM TOPS TO
350. MEAN STORM MOTION VECTOR 22040.
...CORFIDISPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Mar 6, 12:06 PM EST | Mesoscale Discussion | SPC | Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 29 more | 84 min |
| Mar 6, 3:49 PM EST | Mesoscale Discussion | SPC | Beaufort, Bertie, Bladen, Brunswick, Carteret, Chowan and 28 more | 86 min |
Nearby
Tornado Watches in Virginia, 2011Tornado Watches in North Carolina, 2011Every tornado watch in 2011
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.