Alert archive / North Carolina / Tornado Watches in 2008
Tornado Watch 405
The Storm Prediction Center issued this tornado watch at May 31, 2008, 4:23 PM EDT for 29 counties in North Carolina; 29 counties in Virginia. It was in force for 4 hr.
The area
The outline as issued.
The facts
- Issued
- May 31, 2008, 4:23 PM EDT (20:23 UTC)
- Expired
- May 31, 2008, 8:21 PM EDT
- In force
- 4 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 58 counties
Alamance County, NC, Bertie County, NC, Camden County, NC, Caswell County, NC, Chatham County, NC, Chowan County, NC, Currituck County, NC, Davidson County, NC, Durham County, NC, Edgecombe County, NC, Forsyth County, NC, Franklin County, NC, Gates County, NC, Granville County, NC, Guilford County, NC, Halifax County, NC, Hertford County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Pasquotank County, NC, Perquimans County, NC, Person County, NC, Randolph County, NC, Rockingham County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wilson County, NC, Appomattox County, VA, Brunswick County, VA, Campbell County, VA, Charlotte County, VA, City of Chesapeake, VA, City of Danville, 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 Portsmouth, VA, City of Suffolk, VA, City of Virginia Beach, VA, Dinwiddie County, VA, Greensville County, VA, Halifax County, VA, Isle of Wight County, VA, Lunenburg County, VA, Mecklenburg County, VA, Nottoway County, VA, Pittsylvania County, VA, Prince Edward County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA
The radar
The Norfolk radar (KAKQ), 80 km from the middle of the area, began a volume at 20:22 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
- 40%
- One or more EF2 to EF5 tornadoes
- 20%
- Ten or more severe wind reports
- 30%
- One or more gusts of 65 knots or more
- 30%
- Ten or more severe hail reports
- 40%
- One or more hailstones of 2 inches or more
- 30%
- Six or more combined severe hail and wind reports
- 80%
Warnings issued inside it
9 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 31, 5:11 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Orange, Person | 49 min |
| May 31, 5:23 PM EDT | Severe Thunderstorm Warning | RAH | Forsyth, Guilford | 67 min |
| May 31, 5:49 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Orange | 41 min |
| May 31, 6:09 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Orange | 51 min |
| May 31, 6:24 PM EDT | Severe Thunderstorm Warning | RAH | Guilford | 66 min |
| May 31, 6:28 PM EDT | Flash Flood Warning | RAH | Guilford | 2 hr |
| May 31, 6:28 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Granville, Wake | 47 min |
| May 31, 7:02 PM EDT | Severe Thunderstorm Warning | RAH | Davidson, Guilford, Randolph | 38 min |
| May 31, 7:14 PM EDT | Severe Thunderstorm Warning | RAH | Franklin, Granville, Wake | 19 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, 8.4 hours before the alert went out and 155 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
- 680 J/kg
- Mixed-layer CIN
- -42 J/kg
- Mixed-layer LCL
- 674 m above ground
- 0-6 km bulk shear
- 35 kt
- 0-1 km storm-relative helicity
- 216 m²/s²
- 0-3 km storm-relative helicity
- 103 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 4.4
The text
As transmitted, in the capitals the NWS used until 2016.
000
WWUS20 KWNS 312023
SEL5
SPC WW 312023
NCZ000-VAZ000-CWZ000-010100-
URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 405
NWS STORM PREDICTION CENTER NORMAN OK
425 PM EDT SAT MAY 31 2008
THE NWS STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF
NORTHERN NORTH CAROLINA
SOUTHERN VIRGINIA
COASTAL WATERS
EFFECTIVE THIS SATURDAY AFTERNOON AND EVENING FROM 425 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 APPROXIMATELY ALONG AND 45 STATUTE
MILES NORTH AND SOUTH OF A LINE FROM 10 MILES NORTHWEST OF
DANVILLE VIRGINIA TO 45 MILES EAST NORTHEAST OF ELIZABETH CITY
NORTH CAROLINA. FOR A COMPLETE DEPICTION OF THE WATCH SEE THE
ASSOCIATED WATCH OUTLINE UPDATE (WOUS64 KWNS WOU5).
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 402...WW 403...WW 404...
DISCUSSION...ISOLATED SEVERE STORMS...INCLUDING SUPERCELLS AND SMALL
LINES...ARE EXPECTED TO DEVELOP ESEWD ACROSS WW THIS EVENING AS AREA
REMAINS ON FRINGE OF MID LEVEL HEIGHT FALLS. STRONG INSTABILITY AND
EFFECTIVE SHEAR FROM 40-50 KT SHOULD BE MORE THAN ADEQUATE FOR
ROTATING STORMS AND THE POSSIBILITY OF ISOLATED TORNADOES.
OTHERWISE...LARGE HAIL AND DAMAGING WINDS WILL REMAIN LIKELY WITH
THE MORE INTENSE CORES.
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 27025.
...EVANSSPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 31, 4:04 PM EDT | Mesoscale Discussion | SPC | Alamance, Bertie, Camden, Caswell, Chowan, Durham and 13 more | 56 min |
| May 31, 7:37 PM EDT | Mesoscale Discussion | SPC | Alamance, Bertie, Camden, Chatham, Chowan, Currituck and 26 more | 53 min |
| May 31, 8:54 AM EDT | Mesoscale Discussion | SPC | Arlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 13 more | 96 min |
| May 31, 10:20 AM EDT | Tornado Watch | SPC | Arlington, Clarke, Fairfax, Fauquier, Frederick, Loudoun and 12 more | 7 hr |
| May 31, 12:05 PM EDT | Mesoscale Discussion | SPC | Accomack, Albemarle, Alleghany, Amelia, Amherst, Appomattox and 52 more | 55 min |
| May 31, 3:07 PM EDT | Tornado Watch | SPC | Accomack, Albemarle, Amelia, Augusta, Buckingham, Caroline and 49 more | 6 hr |
| May 31, 6:19 PM EDT | Mesoscale Discussion | SPC | Lee | 56 min |
Nearby
Tornado Watches in North Carolina, 2008Tornado Watches in Virginia, 2008Every tornado watch in 2008
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.