Alert archive / Virginia / Mesoscale Discussions in 2018

Mesoscale Discussion 378

May 10, 201813 counties in Maryland; 85 counties in Virginia; Jefferson County, West Virginia

The Storm Prediction Center issued this mesoscale discussion at May 10, 2018, 4:53 PM EDT for 13 counties in Maryland; 85 counties in Virginia; Jefferson County, West Virginia. It was in force for 67 min.

The area

The outline as issued.

The facts

Issued: May 10, 2018, 4:53 PM EDT (20:53 UTC)
Expired: May 10, 2018, 6:00 PM EDT
In force: 67 min
Issued by: the Storm Prediction Center

All 99 counties

Anne Arundel County, MD, Baltimore County, MD, Calvert County, MD, Carroll County, MD, Charles County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Saint Mary's County, MD, Talbot County, MD, Albemarle County, VA, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Arlington County, VA, Augusta 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 Alexandria, VA, City of Charlottesville, VA, City of Colonial Heights, VA, City of Emporia, VA, City of Fairfax, VA, City of Falls Church, VA, City of Franklin, VA, City of Fredericksburg, VA, City of Hampton, VA, City of Harrisonburg, VA, City of Hopewell, VA, City of Lynchburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Newport News, VA, City of Petersburg, VA, City of Poquoson, VA, City of Richmond, VA, City of Staunton, VA, City of Waynesboro, VA, City of Williamsburg, VA, City of Winchester, VA, Clarke County, VA, Culpeper County, VA, Cumberland County, VA, Dinwiddie County, VA, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Fluvanna County, VA, Frederick County, VA, Gloucester County, VA, Goochland County, VA, Greene 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, Loudoun County, VA, Louisa County, VA, Lunenburg County, VA, Madison County, VA, Mathews County, VA, Middlesex County, VA, Nelson County, VA, New Kent County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Page County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Prince William County, VA, Rappahannock County, VA, Richmond County, VA, Rockingham County, VA, Shenandoah County, VA, Southampton County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Warren County, VA, Westmoreland County, VA, York County, VA, Jefferson County, WV

The radar

The Sterling radar (KLWX), 109 km from the middle of the area, began a volume at 20:56 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.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 8.9 hours before the alert went out and 108 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: 0 J/kg
Mixed-layer CIN: No buoyant parcel
Mixed-layer LCL: 1336 m above ground
0-6 km bulk shear: 30 kt
0-1 km storm-relative helicity: 206 m²/s²
0-3 km storm-relative helicity: 171 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

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 10, 12:36 PM EDT	Mesoscale Discussion	SPC	Anne Arundel, Calvert, Charles, Howard, Kent, Montgomery and 5 more	114 min
May 10, 1:14 PM EDT	Severe Thunderstorm Watch	SPC	Anne Arundel, Baltimore, Calvert, Carroll, Charles, Dorchester and 8 more	8 hr
May 10, 7:20 PM EDT	Mesoscale Discussion	SPC	Greensville, City of Emporia	55 min

Nearby

Mesoscale Discussions in Virginia, 2018 Mesoscale Discussions in Maryland, 2018 Mesoscale Discussions in West Virginia, 2018 Every mesoscale discussion in 2018

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.