Alert archive / Virginia / Mesoscale Discussions in 2012

Mesoscale Discussion 1326

June 30, 20127 states

The Storm Prediction Center issued this mesoscale discussion at Jun 30, 2012, 7:39 PM EDT for 7 states. It was in force for 3 hr.

The area

The outline as issued.

The facts

Issued: Jun 30, 2012, 7:39 PM EDT (23:39 UTC)
Expired: Jun 30, 2012, 10:15 PM EDT
In force: 3 hr
Issued by: the Storm Prediction Center
Chance of a watch: 40%

All 171 counties

Kent County, DE, Sussex County, DE, Pike County, KY, Anne Arundel County, MD, Calvert County, MD, Caroline County, MD, Charles County, MD, Dorchester County, MD, Kent County, MD, Prince George's County, MD, Queen Anne's County, MD, Saint Mary's County, MD, Somerset County, MD, Talbot County, MD, Wicomico County, MD, Worcester County, MD, Alleghany County, NC, Ashe County, NC, Avery County, NC, Caldwell County, NC, Caswell County, NC, Forsyth County, NC, Granville County, NC, Guilford County, NC, Person County, NC, Rockingham County, NC, Stokes County, NC, Surry County, NC, Vance County, NC, Warren County, NC, Watauga County, NC, Wilkes County, NC, Yadkin County, NC, Carter County, TN, Johnson County, TN, Sullivan County, TN, Washington County, TN, Accomack County, VA, Albemarle County, VA, Alleghany County, VA, Amelia County, VA, Amherst County, VA, Appomattox County, VA, Arlington County, VA, Augusta County, VA, Bath County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Brunswick County, VA, Buchanan 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 Alexandria, VA, City of Bristol, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Colonial Heights, VA, City of Covington, VA, City of Danville, VA, City of Emporia, VA, City of Fairfax, VA, City of Falls Church, VA, City of Franklin, VA, City of Fredericksburg, VA, City of Galax, VA, City of Hampton, VA, City of Harrisonburg, VA, City of Hopewell, VA, City of Lexington, VA, City of Lynchburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Martinsville, VA, City of Newport News, VA, City of Norfolk, VA, City of Norton, VA, City of Petersburg, VA, City of Poquoson, VA, City of Portsmouth, VA, City of Radford, VA, City of Richmond, VA, City of Roanoke, VA, City of Salem, VA, City of Staunton, VA, City of Waynesboro, VA, City of Williamsburg, VA, Craig County, VA, Culpeper County, VA, Cumberland County, VA, Dickenson County, VA, Dinwiddie County, VA, Essex County, VA, Fairfax County, VA, Fauquier County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Giles County, VA, Gloucester County, VA, Goochland County, VA, Grayson County, VA, Greene County, VA, Greensville County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, Henry County, VA, Highland 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, Madison County, VA, Mathews County, VA, Mecklenburg County, VA, Middlesex County, VA, Montgomery County, VA, Nelson County, VA, New Kent County, VA, Northampton County, VA, Northumberland County, VA, Nottoway County, VA, Orange County, VA, Page County, VA, Patrick County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Prince George County, VA, Prince William County, VA, Pulaski County, VA, Rappahannock County, VA, Richmond County, VA, Roanoke County, VA, Rockbridge County, VA, Rockingham County, VA, Russell County, VA, Scott County, VA, Smyth County, VA, Southampton County, VA, Spotsylvania County, VA, Stafford County, VA, Surry County, VA, Sussex County, VA, Tazewell County, VA, Washington County, VA, Westmoreland County, VA, Wise County, VA, Wythe County, VA, York County, VA, Fayette County, WV, Greenbrier County, WV, Logan County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monroe County, WV, Pocahontas County, WV, Raleigh County, WV, Summers County, WV, Wyoming County, WV

The radar

The Norfolk radar (KAKQ), 139 km from the middle of the area, began a volume at 23:42 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, 11.7 hours before the alert went out and 116 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: 656 J/kg
Mixed-layer CIN: -356 J/kg
Mixed-layer LCL: 1666 m above ground
0-6 km bulk shear: 25 kt
0-1 km storm-relative helicity: -1 m²/s²
0-3 km storm-relative helicity: 47 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

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SPC that day

Everything else SPC issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 29, 10:09 PM EDT	Severe Thunderstorm Watch	SPC	Kent, New Castle, Sussex	4 hr
Jun 29, 10:51 PM EDT	Mesoscale Discussion	SPC	Kent, New Castle, Sussex	84 min
Jun 30, 6:55 PM EDT	Mesoscale Discussion	SPC	Anderson, Bath, Boone, Bourbon, Bracken, Bullitt and 29 more	3 hr
Jun 30, 4:27 PM EDT	Mesoscale Discussion	SPC	Montgomery	3 hr

Nearby

Mesoscale Discussions in Virginia, 2012 Mesoscale Discussions in North Carolina, 2012 Mesoscale Discussions in Maryland, 2012 Every mesoscale discussion in 2012

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.