Alert archive / Virginia / Mesoscale Discussions in 2014

Mesoscale Discussion 731

May 27, 201428 counties in Virginia

The Storm Prediction Center issued this mesoscale discussion at May 27, 2014, 5:48 PM EDT for 28 counties in Virginia. It was in force for 57 min.

The area

The outline as issued.

The facts

Issued: May 27, 2014, 5:48 PM EDT (21:48 UTC)
Expired: May 27, 2014, 6:45 PM EDT
In force: 57 min
Issued by: the Storm Prediction Center
Chance of a watch: 20%

All 28 counties

Amelia County, VA, Appomattox County, VA, Bedford County, VA, Buckingham County, VA, Campbell County, VA, Charlotte County, VA, Chesterfield County, VA, City of Colonial Heights, VA, City of Hopewell, VA, City of Lynchburg, VA, City of Petersburg, VA, City of Richmond, VA, City of Roanoke, VA, Cumberland County, VA, Dinwiddie County, VA, Franklin County, VA, Goochland County, VA, Halifax County, VA, Hanover County, VA, Henrico County, VA, King and Queen County, VA, King William County, VA, Lunenburg County, VA, New Kent County, VA, Nottoway County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA

The radar

The Norfolk radar (KAKQ), 130 km from the middle of the area, began a volume at 21:51 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, 9.8 hours before the alert went out and 98 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: 195 J/kg
Mixed-layer CIN: -61 J/kg
Mixed-layer LCL: 731 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 81 m²/s²
0-3 km storm-relative helicity: 56 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
May 27, 1:43 PM EDT	Mesoscale Discussion	SPC	Clarke, Frederick, Shenandoah, City of Winchester	62 min
May 27, 2:13 PM EDT	Severe Thunderstorm Watch	SPC	Albemarle, Arlington, Augusta, Clarke, Culpeper, Fairfax and 28 more	8 hr
May 27, 6:39 PM EDT	Mesoscale Discussion	SPC	Arlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 14 more	36 min

Nearby

Mesoscale Discussions in Virginia, 2014 Every 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.