Alert archive / Virginia / Mesoscale Discussions in 2019

Mesoscale Discussion 659

May 17, 201939 counties in Virginia; 6 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at May 17, 2019, 9:39 PM EDT for 39 counties in Virginia; 6 counties in West Virginia. It was in force for 66 min.

The area

The outline as issued.

The facts

Issued: May 17, 2019, 9:39 PM EDT (01:39 UTC)
Expired: May 17, 2019, 10:45 PM EDT
In force: 66 min
Issued by: the Storm Prediction Center

All 45 counties

Amelia County, VA, Amherst County, VA, Appomattox County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Buckingham County, VA, Campbell County, VA, Carroll County, VA, Charlotte County, VA, Chesterfield County, VA, City of Buena Vista, VA, City of Colonial Heights, VA, City of Lexington, VA, City of Lynchburg, VA, City of Petersburg, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Cumberland County, VA, Dinwiddie County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Giles County, VA, Goochland County, VA, Louisa County, VA, Lunenburg County, VA, Montgomery County, VA, Nelson County, VA, Nottoway County, VA, Pittsylvania County, VA, Powhatan County, VA, Prince Edward County, VA, Pulaski County, VA, Roanoke County, VA, Tazewell County, VA, Wythe County, VA, McDowell County, WV, Mercer County, WV, Monroe County, WV, Raleigh County, WV, Summers County, WV, Wyoming County, WV

The radar

The Roanoke radar (KFCX), 49 km from the middle of the area, began a volume at 01:40 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 00:00Z, 1.7 hours before the alert went out and 68 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: 102 J/kg
Mixed-layer CIN: -42 J/kg
Mixed-layer LCL: 1594 m above ground
0-6 km bulk shear: 23 kt
0-1 km storm-relative helicity: 97 m²/s²
0-3 km storm-relative helicity: 116 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 1.4

Open this sounding in Storm Lab

The text

As transmitted.

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Nearby

Mesoscale Discussions in Virginia, 2019 Mesoscale Discussions in West Virginia, 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.