Alert archive / Virginia / Mesoscale Discussions in 2016

Mesoscale Discussion 526

May 1, 20164 counties in Kentucky; 25 counties in Virginia; 12 counties in West Virginia

The Storm Prediction Center issued this mesoscale discussion at May 1, 2016, 7:30 PM EDT for 4 counties in Kentucky; 25 counties in Virginia; 12 counties in West Virginia. It was in force for 60 min.

The area

The outline as issued.

The facts

Issued: May 1, 2016, 7:30 PM EDT (23:30 UTC)
Expired: May 1, 2016, 8:30 PM EDT
In force: 60 min
Issued by: the Storm Prediction Center

All 41 counties

Floyd County, KY, Knott County, KY, Martin County, KY, Pike County, KY, Alleghany County, VA, Bedford County, VA, Bland County, VA, Botetourt County, VA, Buchanan County, VA, Carroll County, VA, City of Buena Vista, VA, City of Covington, VA, City of Lexington, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, Craig County, VA, Dickenson County, VA, Floyd County, VA, Franklin County, VA, Giles County, VA, Montgomery County, VA, Patrick County, VA, Pulaski County, VA, Roanoke County, VA, Rockbridge County, VA, Smyth County, VA, Tazewell County, VA, Wythe County, VA, Boone County, WV, Fayette County, WV, Greenbrier County, WV, Lincoln County, WV, Logan County, WV, McDowell County, WV, Mercer County, WV, Mingo County, WV, Monroe County, WV, Raleigh County, WV, Summers County, WV, Wyoming County, WV

The radar

The Roanoke radar (KFCX), 100 km from the middle of the area, began a volume at 23:33 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 watches that followed

Watches SPC issued over any of the same counties within four hours of this discussion.

Severe Thunderstorm Watch 135May 1, 7:45 PM EDT

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 11.5 hours before the alert went out and 160 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: 468 m above ground
0-6 km bulk shear: 45 kt
0-1 km storm-relative helicity: 389 m²/s²
0-3 km storm-relative helicity: 480 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 1, 1:39 PM EDT	Mesoscale Discussion	SPC	Boone, Bracken, Breckinridge, Bullitt, Campbell, Carroll and 18 more	2 hr
May 1, 2:11 PM EDT	Mesoscale Discussion	SPC	Butler, Calloway, Christian, Logan, Muhlenberg, Todd and 1 more	64 min
May 1, 2:36 PM EDT	Severe Thunderstorm Watch	SPC	Adair, Allen, Anderson, Barren, Boone, Bourbon and 67 more	6 hr
May 1, 3:59 PM EDT	Mesoscale Discussion	SPC	Boyd, Breathitt, Carter, Clay, Elliott, Floyd and 13 more	61 min
May 1, 4:12 PM EDT	Severe Thunderstorm Watch	SPC	Bath, Boyd, Breathitt, Carter, Elliott, Estill and 20 more	6 hr
May 1, 6:48 PM EDT	Mesoscale Discussion	SPC	Adair, Allen, Anderson, Barren, Bath, Boone and 72 more	87 min
May 1, 7:45 PM EDT	Severe Thunderstorm Watch	SPC	Alleghany, Bath, Bland, Botetourt, Craig, Floyd and 15 more	3 hr

Nearby

Mesoscale Discussions in Virginia, 2016 Mesoscale Discussions in West Virginia, 2016 Mesoscale Discussions in Kentucky, 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.