Alert archive / Virginia / Severe Thunderstorm Watches in 2015
Severe Thunderstorm Watch 89
The Storm Prediction Center issued this severe thunderstorm watch at Apr 20, 2015, 2:55 PM EDT for 39 counties in North Carolina; 83 counties in Virginia. It was in force for 7 hr.
The area
The outline as issued.
The facts
- Issued
- Apr 20, 2015, 2:55 PM EDT (18:55 UTC)
- Expired
- Apr 20, 2015, 10:00 PM EDT
- In force
- 7 hr
- Issued by
- the Storm Prediction Center
- Largest hail expected
- 2 in
- Strongest gust expected
- 60 kt
All 122 counties
Alamance County, NC, Alleghany County, NC, Anson County, NC, Ashe County, NC, Bertie County, NC, Caswell County, NC, Chatham 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, Harnett County, NC, Hertford 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, Rockingham County, NC, Stanly County, NC, Stokes County, NC, Surry County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Watauga County, NC, Wilkes County, NC, Wilson County, NC, Yadkin County, NC, Alleghany County, VA, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Bath County, VA, Bedford County, VA, Botetourt County, VA, Brunswick County, VA, Buckingham County, VA, Campbell County, VA, Caroline County, VA, Carroll County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Buena Vista, VA, City of Chesapeake, VA, City of Colonial Heights, VA, City of Covington, VA, City of Danville, VA, City of Emporia, VA, City of Franklin, VA, City of Galax, VA, City of Hampton, VA, City of Hopewell, VA, City of Lexington, VA, City of Lynchburg, VA, City of Martinsville, VA, City of Newport News, VA, City of Norfolk, VA, City of Petersburg, VA, City of Portsmouth, VA, City of Radford, VA, City of Richmond, VA, City of Roanoke, VA, City of Salem, VA, City of Suffolk, VA, City of Virginia Beach, VA, City of Williamsburg, VA, Craig County, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Gloucester County, VA, Goochland County, VA, Grayson County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Henry County, VA, Isle of Wight County, VA, James City County, VA, King and Queen County, VA, King William County, VA, Lancaster County, VA, Louisa County, VA, Lunenburg County, VA, Mathews County, VA, Mecklenburg County, VA, Middlesex County, VA, Montgomery County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Patrick County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Pulaski County, VA, Richmond County, VA, Roanoke County, VA, Rockbridge County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, Wythe County, VA, York County, VA
The radar
The Roanoke radar (KFCX), 38 km from the middle of the area, began a volume at 18:56 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
- 2%
- Ten or more severe wind reports
- 50%
- One or more gusts of 65 knots or more
- 10%
- 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%
Warnings issued inside it
25 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 20, 3:09 PM EDT | Severe Thunderstorm Warning | RAH | Chatham, Harnett, Lee | 31 min |
| Apr 20, 3:15 PM EDT | Severe Thunderstorm Warning | RAH | Guilford | 30 min |
| Apr 20, 3:19 PM EDT | Severe Thunderstorm Warning | RNK | Caswell, Rockingham | 56 min |
| Apr 20, 3:20 PM EDT | Severe Thunderstorm Warning | RAH | Chatham | 25 min |
| Apr 20, 3:43 PM EDT | Severe Thunderstorm Warning | RNK | Rockingham | 34 min |
| Apr 20, 3:52 PM EDT | Tornado Warning | RNK | Caswell, Rockingham | 23 min |
| Apr 20, 4:15 PM EDT | Severe Thunderstorm Warning | RNK | Caswell | 30 min |
| Apr 20, 4:19 PM EDT | Severe Thunderstorm Warning | RAH | Person | 41 min |
| Apr 20, 4:24 PM EDT | Severe Thunderstorm Warning | RAH | Franklin, Granville, Vance, Wake | 31 min |
| Apr 20, 4:35 PM EDT | Severe Thunderstorm Warning | RAH | Wake | 26 min |
| Apr 20, 4:37 PM EDT | Severe Thunderstorm Warning | RNK | Alleghany, Ashe | 38 min |
| Apr 20, 5:00 PM EDT | Severe Thunderstorm Warning | RNK | Pulaski, Wythe | 30 min |
| Apr 20, 5:02 PM EDT | Severe Thunderstorm Warning | AKQ | Mecklenburg | 43 min |
| Apr 20, 5:03 PM EDT | Severe Thunderstorm Warning | RAH | Granville, Person | 26 min |
| Apr 20, 5:08 PM EDT | Severe Thunderstorm Warning | RNK | Halifax | 30 min |
| Apr 20, 5:22 PM EDT | Severe Thunderstorm Warning | RAH | Halifax, Warren | 53 min |
| Apr 20, 5:22 PM EDT | Severe Thunderstorm Warning | RNK | Wythe | 23 min |
| Apr 20, 5:29 PM EDT | Severe Thunderstorm Warning | RAH | Randolph | 46 min |
| Apr 20, 5:40 PM EDT | Flash Flood Warning | RNK | Pulaski, Wythe | 3 hr |
| Apr 20, 5:58 PM EDT | Severe Thunderstorm Warning | RAH | Davidson, Montgomery, Moore, Randolph, Stanly | 62 min |
| Apr 20, 6:02 PM EDT | Severe Thunderstorm Warning | AKQ | Northampton | 43 min |
| Apr 20, 6:43 PM EDT | Severe Thunderstorm Warning | AKQ | Hertford, Northampton | 32 min |
| Apr 20, 6:44 PM EDT | Severe Thunderstorm Warning | RAH | Chatham, Durham, Orange, Wake | 46 min |
| Apr 20, 6:45 PM EDT | Severe Thunderstorm Warning | RAH | Montgomery, Moore | 50 min |
| Apr 20, 6:56 PM EDT | Severe Thunderstorm Warning | RAH | Chatham, Lee | 49 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, 6.9 hours before the alert went out and 42 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
- 0 J/kg
- Mixed-layer CIN
- No buoyant parcel
- Mixed-layer LCL
- 668 m above ground
- 0-6 km bulk shear
- 51 kt
- 0-1 km storm-relative helicity
- 28 m²/s²
- 0-3 km storm-relative helicity
- 129 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 |
|---|---|---|---|---|
| Apr 19, 9:06 PM EDT | Mesoscale Discussion | SPC | Bladen, Brunswick, Duplin, Durham, Edgecombe, Franklin and 13 more | 54 min |
| Apr 20, 2:25 AM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Camden, Chowan, Craven, Currituck and 16 more | 95 min |
| Apr 20, 1:03 PM EDT | Mesoscale Discussion | SPC | Alexander, Anson, Buncombe, Burke, Cabarrus, Caldwell and 20 more | 57 min |
| Apr 20, 1:23 PM EDT | Tornado Watch | SPC | Alexander, Avery, Buncombe, Burke, Cabarrus, Caldwell and 20 more | 7 hr |
| Apr 20, 1:54 PM EDT | Mesoscale Discussion | SPC | Alleghany, Stokes, Surry | 3 hr |
| Apr 20, 4:18 PM EDT | Mesoscale Discussion | SPC | Alexander, Buncombe, Burke, Cabarrus, Caldwell, Catawba and 12 more | 57 min |
| Apr 20, 6:27 PM EDT | Mesoscale Discussion | SPC | Alamance, Alleghany, Caswell, Chatham, Durham, Forsyth and 16 more | 93 min |
| Apr 20, 6:45 PM EDT | Mesoscale Discussion | SPC | Alexander, Anson, Avery, Buncombe, Burke, Caldwell and 15 more | 60 min |
| Apr 20, 3:08 PM EDT | Tornado Watch | SPC | Albemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 27 more | 9 hr |
| Apr 20, 5:01 PM EDT | Mesoscale Discussion | SPC | Albemarle, Arlington, Augusta, Caroline, Clarke, Culpeper and 30 more | 119 min |
Nearby
Severe Thunderstorm Watches in Virginia, 2015Severe Thunderstorm Watches in North Carolina, 2015Every severe thunderstorm watch in 2015
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.