Alert archive / Virginia / Mesoscale Discussions in 2014
Mesoscale Discussion 489
The Storm Prediction Center issued this mesoscale discussion at Apr 30, 2014, 5:22 AM EDT for 17 counties in North Carolina; 21 counties in Virginia. It was in force for 53 min.
The area
The outline as issued.
The facts
- Issued
- Apr 30, 2014, 5:22 AM EDT (09:22 UTC)
- Expired
- Apr 30, 2014, 6:15 AM EDT
- In force
- 53 min
- Issued by
- the Storm Prediction Center
- Chance of a watch
- 20%
All 38 counties
Cumberland County, NC, Durham County, NC, Edgecombe County, NC, Franklin County, NC, Granville County, NC, Greene County, NC, Halifax County, NC, Harnett County, NC, Johnston County, NC, Lee County, NC, Nash County, NC, Northampton County, NC, Vance County, NC, Wake County, NC, Warren County, NC, Wayne County, NC, Wilson County, NC, Amelia County, VA, Brunswick County, VA, Charles City County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hopewell, VA, City of Petersburg, VA, City of Richmond, VA, Dinwiddie County, VA, Greensville County, VA, Henrico County, VA, Lunenburg County, VA, Mecklenburg County, VA, Nottoway County, VA, Powhatan County, VA, Prince George County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA
The radar
The Raleigh/Durham radar (KRAX), 54 km from the middle of the area, began a volume at 09:25 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.
The nearest sounding before it
Greensboro/Hi Pt, NC (KGSO), launched 00:00Z, 9.4 hours before the alert went out and 150 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
- 452 m above ground
- 0-6 km bulk shear
- 54 kt
- 0-1 km storm-relative helicity
- 369 m²/s²
- 0-3 km storm-relative helicity
- 416 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.6
The text
As transmitted, in the capitals the NWS used until 2016.
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</html>SPC that day
Everything else SPC issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 30, 12:33 PM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Bladen, Camden, Chowan, Craven and 29 more | 87 min |
| Apr 30, 1:15 PM EDT | Tornado Watch | SPC | Beaufort, Bertie, Camden, Chowan, Currituck, Dare and 18 more | 5 hr |
| Apr 30, 3:47 PM EDT | Mesoscale Discussion | SPC | Beaufort, Bertie, Camden, Carteret, Chowan, Craven and 25 more | 88 min |
| Apr 30, 5:01 PM EDT | Mesoscale Discussion | SPC | Buchanan, Russell, Tazewell, Washington, City of Bristol | 89 min |
Nearby
Mesoscale Discussions in Virginia, 2014Mesoscale Discussions in North Carolina, 2014Every mesoscale discussion in 2014
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.