Alert archive / Virginia / Freeze Warnings in 2020

Freeze Warning 4, NWS Blacksburg, VA

April 21, 202013 counties in Virginia; 4 counties in West Virginia

NWS Blacksburg, VA issued this freeze warning at Apr 21, 2020, 12:12 PM EDT for 13 counties in Virginia; 4 counties in West Virginia. It took effect at Apr 22, 2020, 1:00 AM EDT. It was in force for 8 hr. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued: Apr 21, 2020, 12:12 PM EDT (16:12 UTC)
In effect from: Apr 22, 2020, 1:00 AM EDT
Expired: Apr 22, 2020, 9:00 AM EDT
In force: 8 hr
Issued by: NWS Blacksburg, VA

Counties Alleghany County, VA, Bath County, VA, Bland County, VA, City of Buena Vista, VA, City of Covington, VA, City of Lexington, VA, Craig County, VA, Giles County, VA, Grayson County, VA, Rockbridge County, VA, Smyth County, VA, Tazewell County, VA, Wythe County, VA, Greenbrier County, WV, Mercer County, WV, Monroe County, WV, Summers County, WV

The radar

The Roanoke radar (KFCX), 53 km from the middle of the area, began a volume at 16:13 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, 4.2 hours before the alert went out and 316 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: 1922 m above ground
0-6 km bulk shear: 57 kt
0-1 km storm-relative helicity: 197 m²/s²
0-3 km storm-relative helicity: 207 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.0

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this freeze warning went out, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.

NWS Blacksburg, VA wrote its last area forecast discussion before this freeze warning went out at Apr 21, 10:29 AM EDT, 1 hour 43 minutes earlier.

Area forecast discussion, Apr 21, 10:29 AM EDT, 1 hour 43 minutes before

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Hazardous weather outlook, Apr 21, 4:37 AM EDT, 7 hours 35 minutes before

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The office that day

Everything else NWS Blacksburg, VA issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Apr 21, 3:25 AM EDT	Wind Advisory	RNK	Alleghany, Amherst, Bath, Bedford, Bland, Botetourt and 21 more	19 hr

Nearby

Freeze Warnings in Virginia, 2020 Freeze Warnings in West Virginia, 2020 Every freeze warning in 2020

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.