Alert archive / Virginia / Flash Flood Warnings in 2020

Flash Flood Warning 33, NWS Baltimore/Washington

August 6, 2020Loudoun County, Virginia

NWS Baltimore/Washington issued this flash flood warning at Aug 6, 2020, 10:09 PM EDT for Loudoun County, Virginia. It was in force for 4 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: Aug 6, 2020, 10:09 PM EDT (02:09 UTC)
Expired: Aug 7, 2020, 2:04 AM EDT
In force: 4 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

County Loudoun County, VA

The radar

The Sterling radar (KLWX), 18 km from the middle of the area, began a volume at 02:12 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.

What forecasters said that day

The local office's own words before this flash flood 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 flash flood warning went out at Aug 6, 9:19 PM EDT, 50 minutes earlier.

Area forecast discussion, Aug 6, 9:19 PM EDT, 50 minutes before

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Hazardous weather outlook, Aug 6, 1:52 PM EDT, 8 hours 17 minutes before

Hazardous Weather Outlook
National Weather Service Baltimore MD/Washington DC
152 PM EDT Thu Aug 6 2020

ANZ530>543-DCZ001-MDZ011-013-014-016>018-508-VAZ052>057-071000-
Chesapeake Bay north of Pooles Island MD-
Chesapeake Bay from Pooles Island to Sandy Point MD-
Chesapeake Bay from Sandy Point to North Beach MD-
Chesapeake Bay from North Beach to Drum Point MD-
Chesapeake Bay from Drum Point MD to Smith Point VA-
Tidal Potomac from Key Bridge to Indian Head MD-
Tidal Potomac from Indian Head to Cobb Island MD-
Tidal Potomac from Cobb Island MD to Smith Point VA-
Patapsco River including Baltimore Harbor-
Chester River to Queenstown MD-Eastern Bay-
Choptank River to Cambridge MD and the Little Choptank River-
Patuxent River to Broomes Island MD-
Tangier Sound and the inland waters surrounding Bloodsworth
Island-District of Columbia-Southern Baltimore-Prince Georges-
Anne Arundel-Charles-St. Marys-Calvert-Southeast Harford-
Prince William/Manassas/Manassas Park-Fairfax-
Arlington/Falls Church/Alexandria-Stafford-Spotsylvania-
King George-
152 PM EDT Thu Aug 6 2020

This Hazardous Weather Outlook is for the Maryland portion of the
Chesapeake Bay, Tidal Potomac River, and adjacent counties in
central Maryland and northern Virginia as well as the District of
Columbia.

.DAY ONE...This Afternoon and Tonight

A Flash Flood Watch is in effect through tonight. Thunderstorms
may produce scattered instances of flash flooding.

Isolated severe thunderstorms are also possible through this
evening.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Scattered thunderstorms may produce isolated instances of
flooding Friday.

.SPOTTER INFORMATION STATEMENT...

Please report any wind damage or flooding to the National Weather
Service.

MDZ003>006-501>507-VAZ025>031-036>040-050-051-501>508-WVZ050>053-
055-501>506-071000-
Washington-Frederick MD-Carroll-Northern Baltimore-
Extreme Western Allegany-Central and Eastern Allegany-
Northwest Montgomery-Central and Southeast Montgomery-
Northwest Howard-Central and Southeast Howard-Northwest Harford-
Augusta-Rockingham-Shenandoah-Frederick VA-Page-Warren-Clarke-
Nelson-Albemarle-Greene-Madison-Rappahannock-Orange-Culpeper-
Northern Fauquier-Southern Fauquier-Western Highland-
Eastern Highland-Western Loudoun-Eastern Loudoun-
Northern Virginia Blue Ridge-Central Virginia Blue Ridge-
Hampshire-Morgan-Berkeley-Jefferson-Hardy-Western Grant-
Eastern Grant-Western Mineral-Eastern Mineral-Western Pendleton-
Eastern Pendleton-
152 PM EDT Thu Aug 6 2020

This Hazardous Weather Outlook is for eastern West Virginia,
northern and central Virginia, and central and western Maryland
with the exception of Garrett County.

.DAY ONE...This Afternoon and Tonight

A Flash Flood Watch is in effect through tonight for areas along
and east of Interstate 81. Thunderstorms may produce scattered
instances of flash flooding.

Isolated severe thunderstorms are also possible through this
evening.

.DAYS TWO THROUGH SEVEN...Friday through Wednesday

Scattered thunderstorms may produce isolated instances of
flooding Friday.

.SPOTTER INFORMATION STATEMENT...

Please report any wind damage or flooding to the National Weather
Service.

In the hours before

Local storm report, Aug 6, 9:26 PM EDT, 43 minutes before

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Local storm report, Aug 6, 9:27 PM EDT, 42 minutes before

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Local storm report, Aug 6, 10:00 PM EDT, 9 minutes before

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Local storm report, Aug 6, 10:04 PM EDT, 5 minutes before

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Local storm report, Aug 6, 10:05 PM EDT, 4 minutes before

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Local storm report, Aug 6, 10:06 PM EDT, 3 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 6, 8:54 PM EDT	Areal Flood Warning	LWX	Loudoun	6 hr
Aug 6, 8:56 PM EDT	Severe Thunderstorm Warning	LWX	Loudoun	49 min
Aug 6, 9:06 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Loudoun	3 hr
Aug 6, 9:34 PM EDT	Areal Flood Warning	LWX	Spotsylvania	2 hr
Aug 6, 10:13 PM EDT	Flash Flood Warning EmergencyCatastrophic damage threat	LWX	Loudoun	96 min
Aug 7, 2:04 AM EDT	Areal Flood Warning	LWX	Loudoun	3 hr
Aug 7, 2:21 AM EDT	Areal Flood Warning	LWX	Loudoun	5 hr
Aug 7, 3:46 AM EDT	Flash Flood Watch	LWX	Albemarle, Amherst, Arlington, Augusta, Culpeper, Fairfax and 22 more	21 hr
Aug 7, 2:33 PM EDT	Severe Thunderstorm Warning	LWX	Augusta, Rockingham	42 min
Aug 7, 4:39 PM EDT	Severe Thunderstorm Warning	LWX	Augusta, Rockingham, City of Staunton	51 min
Aug 7, 5:13 PM EDT	Severe Thunderstorm Warning	LWX	Augusta, City of Waynesboro	47 min
Aug 7, 5:39 PM EDT	Special Marine Warning	LWX		2 hr
Aug 7, 6:52 PM EDT	Special Marine Warning	LWX		2 hr
Aug 7, 7:08 PM EDT	Severe Thunderstorm Warning	LWX	Augusta, City of Waynesboro	52 min
Aug 6, 9:07 PM EDT	Severe Thunderstorm Warning	LWX	Frederick	38 min
Aug 7, 2:08 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Washington	52 min
Aug 7, 2:48 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick	36 min
Aug 7, 4:26 PM EDT	Severe Thunderstorm Warning	LWX	Allegany	49 min
Aug 7, 4:53 PM EDT	Severe Thunderstorm Warning	LWX	Allegany	27 min
Aug 7, 5:03 PM EDT	Severe Thunderstorm Warning	LWX	Allegany	42 min
Aug 7, 5:28 PM EDT	Areal Flood Warning	LWX	Baltimore, Harford	4 hr
Aug 7, 5:36 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	39 min
Aug 7, 6:04 PM EDT	Severe Thunderstorm Warning	LWX	Harford	41 min
Aug 7, 6:12 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	48 min
Aug 7, 6:15 PM EDT	Areal Flood Warning	LWX	Harford	6 hr
Aug 7, 7:39 PM EDT	Areal Flood Warning	LWX	Anne Arundel, Baltimore	5 hr
Aug 7, 7:41 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Baltimore, Harford	104 min
Aug 7, 5:15 PM EDT	Severe Thunderstorm Warning	LWX	Pendleton	45 min
Aug 7, 5:40 PM EDT	Severe Thunderstorm Warning	LWX	Pendleton	50 min

Nearby

Flash Flood Warnings in Virginia, 2020 Every flash flood 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; radar from the NEXRAD Level II archive.