Alert archive / Virginia / Mesoscale Discussions in 2019

Mesoscale Discussion 359

April 15, 20196 counties in North Carolina; 46 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at Apr 15, 2019, 12:07 AM EDT for 6 counties in North Carolina; 46 counties in Virginia. It was in force for 113 min.

The area

The outline as issued.

The facts

Issued: Apr 15, 2019, 12:07 AM EDT (04:07 UTC)
Expired: Apr 15, 2019, 2:00 AM EDT
In force: 113 min
Issued by: the Storm Prediction Center
Chance of a watch: 80%

All 52 counties

Franklin County, NC, Halifax County, NC, Nash County, NC, Northampton County, NC, Vance County, NC, Warren County, NC, Amelia County, VA, Brunswick County, VA, Caroline County, VA, Charles City County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Franklin, VA, City of Hampton, VA, City of Hopewell, VA, City of Newport News, VA, City of Petersburg, VA, City of Poquoson, VA, City of Richmond, VA, City of Suffolk, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Gloucester County, VA, Goochland County, VA, Greensville County, VA, Hanover County, VA, Henrico 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, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Richmond County, VA, Southampton County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA, York County, VA

The radar

The Norfolk radar (KAKQ), 51 km from the middle of the area, began a volume at 04:09 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Tornado Watch 73Apr 15, 12:40 AM EDT

The nearest sounding before it

Roanoke, VA (KRNK), launched 00:00Z, 4.1 hours before the alert went out and 172 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.

Skew-T log-p

Temperature in red, dew point in green, the mixed-layer parcel dashed.

Hodograph

The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.

Mixed-layer CAPE: 215 J/kg
Mixed-layer CIN: -26 J/kg
Mixed-layer LCL: 874 m above ground
0-6 km bulk shear: 92 kt
0-1 km storm-relative helicity: 305 m²/s²
0-3 km storm-relative helicity: 332 m²/s²
Significant tornado parameter: 0.4
Supercell composite: 7.2

Open this sounding in Storm Lab

The text

As transmitted.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 14, 10:09 PM EDT	Mesoscale Discussion	SPC	Alamance, Alexander, Alleghany, Anson, Burke, Cabarrus and 26 more	96 min
Apr 14, 10:14 PM EDT	Tornado Watch	SPC	Alamance, Alexander, Alleghany, Anson, Burke, Cabarrus and 37 more	6 hr
Apr 15, 12:41 AM EDT	Tornado Watch	SPC	Bertie, Camden, Chowan, Currituck, Edgecombe, Franklin and 11 more	5 hr
Apr 15, 2:18 AM EDT	Mesoscale Discussion	SPC	Beaufort, Bladen, Brunswick, Carteret, Columbus, Craven and 21 more	117 min
Apr 15, 2:30 AM EDT	Mesoscale Discussion	SPC	Northampton	60 min
Apr 14, 8:31 PM EDT	Mesoscale Discussion	SPC	Alleghany, Bland, Craig, Giles, Montgomery, Pulaski and 5 more	59 min

Nearby

Mesoscale Discussions in Virginia, 2019 Mesoscale Discussions in North Carolina, 2019 Every mesoscale discussion in 2019

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.