Alert archive / Virginia / Severe Thunderstorm Warnings in 2020

Severe Thunderstorm Warning 413, NWS Baltimore/Washington

August 28, 2020Fauquier County, Rappahannock County, Virginia

NWS Baltimore/Washington issued this severe thunderstorm warning at Aug 28, 2020, 5:21 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 28, 2020, 5:21 PM EDT (21:21 UTC)
Expired: Aug 28, 2020, 6:00 PM EDT
In force: 39 min
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Hail: 1.0 in
Wind: 60.0 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 21:23 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 watch it was issued in

The SPC watch in force over the same counties when this warning went out.

Issued	Product	Office	Lasted
Aug 28, 1:37 PM EDT	Severe Thunderstorm Watch	SPC	8 hr

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 9.4 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: 511 J/kg
Mixed-layer CIN: -119 J/kg
Mixed-layer LCL: 1109 m above ground
0-6 km bulk shear: 24 kt
0-1 km storm-relative helicity: 102 m²/s²
0-3 km storm-relative helicity: 50 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 Baltimore/Washington wrote its last area forecast discussion before this severe thunderstorm warning went out at Aug 28, 2:33 PM EDT, 2 hours 48 minutes earlier.

Area forecast discussion, Aug 28, 2:33 PM EDT, 2 hours 48 minutes before

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Hazardous weather outlook, Aug 28, 5:19 PM EDT, 2 minutes before

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In the hours before

Local storm report, Aug 28, 2:45 PM EDT, 2 hours 36 minutes before

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE BALTIMORE MD/WASHINGTON DC
245 PM EDT FRI AUG 28 2020

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0155 PM     MARINE TSTM WIND 2 E HAVRE DE GRACE      39.54N  76.06W
08/28/2020  M41 MPH          ANZ530             MD   MESONET

&&

EVENT NUMBER LWX2002256

DH

Local storm report, Aug 28, 4:00 PM EDT, 1 hour 21 minutes before

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Local storm report, Aug 28, 5:03 PM EDT, 18 minutes before

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Local storm report, Aug 28, 5:11 PM EDT, 10 minutes before

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Local storm report, Aug 28, 5:14 PM EDT, 7 minutes before

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Local storm report, Aug 28, 5:17 PM EDT, 4 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 28, 12:51 PM EDT	Small Craft Advisory	LWX		44 hr
Aug 28, 12:51 PM EDT	Small Craft Advisory	LWX		41 hr
Aug 28, 1:44 PM EDT	Special Marine Warning	LWX		46 min
Aug 28, 3:52 PM EDT	Special Marine Warning	LWX		98 min
Aug 28, 4:13 PM EDT	Special Marine Warning	LWX		92 min
Aug 28, 4:34 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, City of Winchester	41 min
Aug 28, 4:59 PM EDT	Flash Flood Watch	LWX	Arlington, Clarke, Culpeper, Fairfax, Fauquier, Frederick and 13 more	11 hr
Aug 28, 5:25 PM EDT	Special Marine Warning	LWX		95 min
Aug 28, 5:29 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier, Loudoun, Prince William	46 min
Aug 28, 5:39 PM EDT	Special Marine Warning	LWX		57 min
Aug 28, 5:45 PM EDT	Severe Thunderstorm Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Fairfax, City of Falls Church	45 min
Aug 28, 5:52 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Loudoun, Prince William, City of Fairfax	38 min
Aug 28, 6:01 PM EDT	Special Marine Warning	LWX		44 min
Aug 28, 6:17 PM EDT	Areal Flood Warning	LWX	Arlington, Fairfax, City of Alexandria, City of Falls Church	5 hr
Aug 28, 6:17 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, City of Alexandria	43 min
Aug 28, 6:22 PM EDT	Areal Flood Warning	LWX	Rockingham	2 hr
Aug 28, 6:30 PM EDT	Severe Thunderstorm Warning	LWX	Rockingham, Shenandoah	45 min
Aug 28, 6:32 PM EDT	Areal Flood Warning	LWX	Arlington	5 hr
Aug 28, 6:38 PM EDT	Special Marine Warning	LWX		97 min
Aug 28, 6:51 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Arlington, Fairfax, City of Alexandria, City of Falls Church	93 min
Aug 28, 6:57 PM EDT	Special Marine Warning	LWX		93 min
Aug 28, 7:24 PM EDT	Severe Thunderstorm Warning	LWX	Rockingham	35 min
Aug 28, 7:43 PM EDT	Special Marine Warning	LWX		92 min
Aug 28, 7:54 PM EDT	Areal Flood Warning	LWX	Page, Rockingham, Shenandoah	47 min
Aug 27, 8:30 PM EDT	Severe Thunderstorm Warning	LWX	Allegany	15 min
Aug 28, 1:51 PM EDT	Severe Thunderstorm Warning	LWX	Harford	24 min
Aug 28, 3:02 PM EDT	Severe Thunderstorm Warning	LWX	Washington	43 min
Aug 28, 3:07 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll, Frederick, Howard, Montgomery	38 min
Aug 28, 3:19 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll, Frederick, Harford	41 min
Aug 28, 3:45 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll	21 min
Aug 28, 4:02 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	43 min
Aug 28, 4:33 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Frederick, Howard, Montgomery, Prince George's	42 min
Aug 28, 6:55 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Calvert, Prince George's	33 min
Aug 28, 7:19 PM EDT	Areal Flood Warning	LWX	Prince George's	112 min
Aug 28, 7:41 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Calvert, Charles, Prince George's, Saint Mary's	49 min

Nearby

Severe Thunderstorm Warnings in Virginia, 2020 Every 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.