Alert archive / West Virginia / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 171, NWS Blacksburg, VA

August 27, 2020Greenbrier County, West Virginia

NWS Blacksburg, VA issued this severe thunderstorm warning at Aug 27, 2020, 4:34 PM EDT for Greenbrier County, West Virginia. It was in force for 56 min. No storm report in the archive falls inside the area while it was in force.

The area

The counties it named.

The facts

Issued
Aug 27, 2020, 4:34 PM EDT (20:34 UTC)
Expired
Aug 27, 2020, 5:30 PM EDT
In force
56 min
Issued by
NWS Blacksburg, VA
Area
Storm-based polygon
Hail
1.0 in
Wind
60.0 mph

County Greenbrier County, WV

The radar

The Roanoke radar (KFCX), 104 km from the middle of the area, began a volume at 20:36 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, 8.6 hours before the alert went out and 118 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-pSkew-T log-p diagram, Roanoke, VA at 12:00Z on 2020-08-27Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 162 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 12:00Z on 2020-08-27The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 57 square meters per square second.193958Sfc1 km3 km6 km9 kmRMLM
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
162 J/kg
Mixed-layer CIN
-178 J/kg
Mixed-layer LCL
951 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
57 m²/s²
0-3 km storm-relative helicity
5 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 severe thunderstorm 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 severe thunderstorm warning went out at Aug 26, 7:50 PM EDT, 20 hours 44 minutes earlier.

Area forecast discussion, Aug 26, 7:50 PM EDT, 20 hours 44 minutes before
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The office that day

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

IssuedProductOfficeCountiesLasted
Aug 27, 4:23 PM EDTSpecial Weather StatementRNKAppomattox37 min
Aug 27, 5:23 PM EDTSpecial Weather StatementRNKPatrick37 min
Aug 27, 5:29 PM EDTSpecial Weather StatementRNKAlleghany31 min
Aug 27, 6:17 PM EDTSpecial Weather StatementRNKCity of Buena Vista43 min
Aug 27, 7:00 PM EDTSpecial Weather StatementRNKCity of Lynchburg30 min
Aug 27, 5:52 PM EDTSpecial Weather StatementRNKStokes23 min
Aug 27, 6:27 PM EDTSpecial Weather StatementRNKRockingham33 min
Aug 27, 5:47 PM EDTAreal Flood AdvisoryRNKGreenbrier3 hr
Aug 27, 6:33 PM EDTSpecial Weather StatementRNKGreenbrier42 min

Nearby

Severe Thunderstorm Warnings in West Virginia, 2020Every severe thunderstorm 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.