Alert archive / Virginia / Mesoscale Discussions in 2016

Mesoscale Discussion 535

May 2, 2016Charles County, Maryland; 53 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at May 2, 2016, 6:34 PM EDT for Charles County, Maryland; 53 counties in Virginia. It was in force for 56 min.

The area

The outline as issued.

The facts

Issued: May 2, 2016, 6:34 PM EDT (22:34 UTC)
Expired: May 2, 2016, 7:30 PM EDT
In force: 56 min
Issued by: the Storm Prediction Center

All 54 counties

Charles County, MD, Albemarle County, VA, Amelia County, VA, Appomattox County, VA, Arlington County, VA, Brunswick County, VA, Buckingham County, VA, Caroline County, VA, Charles City County, VA, Charlotte County, VA, Chesterfield County, VA, City of Alexandria, VA, City of Charlottesville, VA, City of Colonial Heights, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Hopewell, VA, City of Petersburg, VA, City of Richmond, VA, City of Williamsburg, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fairfax County, VA, Fluvanna County, VA, Gloucester County, VA, Goochland County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Isle of Wight County, VA, James City County, VA, King and Queen County, VA, King George County, VA, King William County, VA, Lancaster County, VA, Louisa County, VA, Lunenburg County, VA, Middlesex County, VA, Nelson County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Prince William County, VA, Richmond County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Westmoreland County, VA

The radar

The Norfolk radar (KAKQ), 93 km from the middle of the area, began a volume at 22:37 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

Roanoke, VA (KRNK), launched 12:00Z, 10.6 hours before the alert went out and 147 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: -41 J/kg
Mixed-layer LCL: 706 m above ground
0-6 km bulk shear: 37 kt
0-1 km storm-relative helicity: 115 m²/s²
0-3 km storm-relative helicity: 115 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

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
May 2, 2:17 PM EDT	Severe Thunderstorm Watch	SPC	Anne Arundel, Calvert, Charles, Howard, Montgomery, Prince George's and 1 more	8 hr
May 2, 1:34 PM EDT	Mesoscale Discussion	SPC	Albemarle, Alleghany, Amelia, Amherst, Appomattox, Augusta and 61 more	116 min
May 2, 2:43 PM EDT	Mesoscale Discussion	SPC	Amelia, Brunswick, Charles City, Chesterfield, Dinwiddie, Greensville and 21 more	62 min
May 2, 5:38 PM EDT	Severe Thunderstorm Watch	SPC	Amelia, Brunswick, Caroline, Charles City, Chesterfield, Cumberland and 41 more	5 hr

Nearby

Mesoscale Discussions in Virginia, 2016 Mesoscale Discussions in Maryland, 2016 Every mesoscale discussion in 2016

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.