Alert archive / Virginia / Severe Thunderstorm Warnings in 2018

Severe Thunderstorm Warning 253, NWS Baltimore/Washington

August 17, 2018Fauquier County, Rappahannock County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Aug 17, 2018, 5:06 PM EDT for Fauquier County, Rappahannock County, Virginia. It was in force for 39 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 17, 2018, 5:06 PM EDT (21:06 UTC)
Expired: Aug 17, 2018, 5:45 PM EDT
In force: 39 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Hail: 1.0 in
Wind: 70.0 mph

Counties Fauquier County, VA, Rappahannock County, VA

The radar

The Sterling radar (KLWX), 52 km from the middle of the area, began a volume at 21:10 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, 9.1 hours before the alert went out and 57 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: 750 J/kg
Mixed-layer CIN: -101 J/kg
Mixed-layer LCL: 1186 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 80 m²/s²
0-3 km storm-relative helicity: 69 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.

Hazardous weather outlook, Aug 16, 7:59 PM EDT, 21 hours 7 minutes before

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The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Aug 17, 2:06 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Shenandoah, City of Winchester	54 min
Aug 17, 2:53 PM EDT	Severe Thunderstorm Warning	LWX	Shenandoah	67 min
Aug 17, 3:15 PM EDT	Severe Thunderstorm Warning	LWX	Page, Shenandoah	45 min
Aug 17, 3:32 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, Warren	43 min
Aug 17, 4:41 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Fauquier, Loudoun, Rappahannock, Warren	49 min
Aug 17, 4:48 PM EDT	Severe Thunderstorm Warning	LWX	Rockingham, City of Harrisonburg	18 min
Aug 17, 4:58 PM EDT	Severe Thunderstorm Warning	LWX	Page	47 min
Aug 17, 5:49 PM EDT	Severe Thunderstorm Warning	LWX	Madison	41 min
Aug 17, 5:53 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Rappahannock	36 min
Aug 17, 5:55 PM EDT	Special Marine Warning	LWX		67 min
Aug 17, 7:45 PM EDT	Severe Thunderstorm Warning	LWX	Greene, Madison, Page, Rockingham	45 min
Aug 16, 8:33 PM EDT	Coastal Flood Advisory	LWX	Harford	6 hr
Aug 17, 3:24 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Washington	51 min
Aug 17, 3:40 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick, Washington	65 min
Aug 17, 3:26 PM EDT	Severe Thunderstorm Warning	LWX	Hardy	49 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2018 Every severe thunderstorm warning in 2018

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.