Alert archive / Virginia / Severe Thunderstorm Watches in 2011
Severe Thunderstorm Watch 387
The Storm Prediction Center issued this severe thunderstorm watch at May 27, 2011, 12:06 PM EDT for 40 counties in North Carolina; 16 counties in South Carolina; 58 counties in Virginia. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- May 27, 2011, 12:06 PM EDT (16:06 UTC)
- Expired
- May 27, 2011, 7:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 1.5 in
- Strongest gust expected
- 60 kt
All 114 counties
Alamance County, NC, Anson County, NC, Cabarrus County, NC, Caswell County, NC, Chatham County, NC, Cumberland County, NC, Davidson County, NC, Davie County, NC, Durham County, NC, Edgecombe County, NC, Forsyth County, NC, Franklin County, NC, Granville County, NC, Guilford County, NC, Halifax County, NC, Harnett County, NC, Hoke County, NC, Johnston County, NC, Lee County, NC, Montgomery County, NC, Moore County, NC, Nash County, NC, Northampton County, NC, Orange County, NC, Person County, NC, Randolph County, NC, Richmond County, NC, Robeson County, NC, Rockingham County, NC, Rowan County, NC, Sampson County, NC, Scotland County, NC, Stanly County, NC, Stokes County, NC, Union County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wayne County, NC, Wilson County, NC, Bamberg County, SC, Calhoun County, SC, Chesterfield County, SC, Clarendon County, SC, Darlington County, SC, Dillon County, SC, Florence County, SC, Kershaw County, SC, Lancaster County, SC, Lee County, SC, Marion County, SC, Marlboro County, SC, Orangeburg County, SC, Richland County, SC, Sumter County, SC, Williamsburg County, SC, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Bedford County, VA, Botetourt County, VA, Brunswick County, VA, Buckingham County, VA, Campbell County, VA, Caroline County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Buena Vista, VA, City of Colonial Heights, VA, City of Danville, VA, City of Emporia, VA, City of Franklin, VA, City of Hopewell, VA, City of Lexington, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Petersburg, VA, City of Richmond, VA, City of Roanoke, VA, City of Salem, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fluvanna County, VA, Franklin County, VA, Goochland County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Henry County, VA, James City County, VA, King and Queen County, VA, King William County, VA, Louisa County, VA, Lunenburg County, VA, Mecklenburg County, VA, New Kent County, VA, Nottoway County, VA, Patrick County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Richmond County, VA, Roanoke County, VA, Rockbridge County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA
The radar
The Raleigh/Durham radar (KRAX), 82 km from the middle of the area, began a volume at 16:06 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
- 20%
- One or more EF2 to EF5 tornadoes
- 5%
- Ten or more severe wind reports
- 70%
- 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
- 20%
- Six or more combined severe hail and wind reports
- 90%
Warnings issued inside it
35 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 27, 12:25 PM EDT | Severe Thunderstorm Warning | CAE | Chesterfield | 35 min |
| May 27, 12:29 PM EDT | Severe Thunderstorm Warning | GSP | Cabarrus, Davie, Rowan | 61 min |
| May 27, 12:30 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Granville, Wake | 45 min |
| May 27, 12:37 PM EDT | Severe Thunderstorm Warning | ILM | Williamsburg | 53 min |
| May 27, 12:46 PM EDT | Severe Thunderstorm Warning | CAE | Chesterfield | 44 min |
| May 27, 1:14 PM EDT | Severe Thunderstorm Warning | RAH | Granville, Vance | 61 min |
| May 27, 1:15 PM EDT | Severe Thunderstorm Warning | GSP | Union | 34 min |
| May 27, 1:25 PM EDT | Severe Thunderstorm Warning | RAH | Chatham, Durham, Orange | 57 min |
| May 27, 1:35 PM EDT | Flash Flood Warning | RAH | Chatham, Durham, Granville, Orange | 3 hr |
| May 27, 1:52 PM EDT | Severe Thunderstorm Warning | RAH | Davidson, Forsyth, Guilford | 46 min |
| May 27, 1:54 PM EDT | Severe Thunderstorm Warning | ILM | Robeson | 51 min |
| May 27, 1:59 PM EDT | Severe Thunderstorm Warning | RAH | Chatham, Durham, Wake | 61 min |
| May 27, 2:00 PM EDT | Severe Thunderstorm Warning | CAE | Bamberg, Barnwell, Orangeburg | 60 min |
| May 27, 2:11 PM EDT | Severe Thunderstorm Warning | RAH | Granville, Vance, Warren | 49 min |
| May 27, 2:18 PM EDT | Severe Thunderstorm Warning | RNK | Caswell, Rockingham, Stokes | 57 min |
| May 27, 2:19 PM EDT | Severe Thunderstorm Warning | RAH | Cumberland, Harnett, Hoke | 56 min |
| May 27, 2:26 PM EDT | Severe Thunderstorm Warning | CAE | Chesterfield, Lancaster | 64 min |
| May 27, 2:44 PM EDT | Severe Thunderstorm Warning | CAE | Chesterfield, Kershaw | 61 min |
| May 27, 2:45 PM EDT | Flash Flood Warning | RAH | Harnett, Wake | 2 hr |
| May 27, 2:55 PM EDT | Severe Thunderstorm Warning | RAH | Durham, Franklin, Granville, Johnston, Wake | 44 min |
| May 27, 3:01 PM EDT | Severe Thunderstorm Warning | CAE | Chesterfield, Kershaw, Lancaster | 44 min |
| May 27, 3:15 PM EDT | Severe Thunderstorm Warning | RNK | Appomattox, Bedford, Campbell, Charlotte, Halifax, Pittsylvania and 1 more | 60 min |
| May 27, 3:22 PM EDT | Severe Thunderstorm Warning | CAE | Calhoun, Clarendon, Sumter | 53 min |
| May 27, 3:52 PM EDT | Severe Thunderstorm Warning | GSP | Cabarrus, Mecklenburg | 53 min |
| May 27, 3:55 PM EDT | Severe Thunderstorm Warning | AKQ | Brunswick, Lunenburg, Nottoway | 20 min |
| May 27, 4:09 PM EDT | Severe Thunderstorm Warning | GSP | Union | 46 min |
| May 27, 4:21 PM EDT | Flash Flood Warning | RAH | Durham, Orange | 97 min |
| May 27, 4:27 PM EDT | Severe Thunderstorm Warning | CAE | Calhoun, Clarendon, Sumter | 48 min |
| May 27, 4:36 PM EDT | Severe Thunderstorm Warning | GSP | Cabarrus, Rowan | 54 min |
| May 27, 4:40 PM EDT | Severe Thunderstorm Warning | CAE | Richland, Sumter | 50 min |
| May 27, 4:41 PM EDT | Severe Thunderstorm Warning | GSP | Cabarrus, Gaston, Mecklenburg | 64 min |
| May 27, 5:02 PM EDT | Severe Thunderstorm Warning | RAH | Davidson, Forsyth | 43 min |
| May 27, 5:16 PM EDT | Severe Thunderstorm Warning | GSP | Davie, Rowan | 44 min |
| May 27, 6:00 PM EDT | Severe Thunderstorm Warning | AKQ | Caroline, Hanover, Louisa | 15 min |
| May 27, 6:43 PM EDT | Severe Thunderstorm Warning | CAE | Fairfield, Kershaw, Richland | 47 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
Greensboro/Hi Pt, NC (KGSO), launched 12:00Z, 4.1 hours before the alert went out and 65 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
- 31 J/kg
- Mixed-layer CIN
- -292 J/kg
- Mixed-layer LCL
- 831 m above ground
- 0-6 km bulk shear
- 39 kt
- 0-1 km storm-relative helicity
- 93 m²/s²
- 0-3 km storm-relative helicity
- 106 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 26, 11:22 PM EDT | Mesoscale Discussion | SPC | Caswell, Forsyth, Rockingham, Stokes, Yadkin | 113 min |
| May 27, 11:26 AM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Caswell, Chatham, Cumberland, Durham and 27 more | 94 min |
| May 27, 3:29 PM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Bertie, Bladen, Caswell, Chatham and 37 more | 91 min |
| May 27, 6:24 PM EDT | Mesoscale Discussion | SPC | Alamance, Anson, Bladen, Caswell, Chatham, Columbus and 29 more | 66 min |
| May 27, 12:24 PM EDT | Mesoscale Discussion | SPC | Arlington, Caroline, Clarke, Culpeper, Fairfax, Fauquier and 24 more | 96 min |
| May 27, 12:57 PM EDT | Severe Thunderstorm Watch | SPC | Albemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 28 more | 9 hr |
| May 27, 6:14 PM EDT | Mesoscale Discussion | SPC | Arlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 12 more | 2 hr |
Nearby
Severe Thunderstorm Watches in Virginia, 2011Severe Thunderstorm Watches in North Carolina, 2011Severe Thunderstorm Watches in South Carolina, 2011Every severe thunderstorm 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.