Alert archive / Maryland / Flash Flood Warnings in 2022

Flash Flood Warning 48, NWS Baltimore/Washington

August 4, 2022Arlington County, Virginia; Montgomery County, Prince George's County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Aug 4, 2022, 10:16 PM EDT for Arlington County, Virginia; Montgomery County, Prince George's County, Maryland. It was in force for 2 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 4, 2022, 10:16 PM EDT (02:16 UTC)
Expired: Aug 5, 2022, 12:41 AM EDT
In force: 2 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Flood severity: None

Counties Montgomery County, MD, Prince George's County, MD, Arlington County, VA

The radar

The Sterling radar (KLWX), 38 km from the middle of the area, began a volume at 02:18 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

Wallops Is Stn, VA (KWAL), launched 00:00Z, 2.3 hours before the alert went out and 183 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: 2653 J/kg
Mixed-layer CIN: -33 J/kg
Mixed-layer LCL: 1015 m above ground
0-6 km bulk shear: 8 kt
0-1 km storm-relative helicity: 61 m²/s²
0-3 km storm-relative helicity: 110 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 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 4, 9:18 PM EDT, 58 minutes earlier.

Area forecast discussion, Aug 4, 9:18 PM EDT, 58 minutes before

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Hazardous weather outlook, Aug 4, 7:41 PM EDT, 2 hours 35 minutes before

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In the hours before

Local storm report, Aug 4, 8:59 PM EDT, 1 hour 17 minutes before

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Local storm report, Aug 4, 9:00 PM EDT, 1 hour 16 minutes before

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Local storm report, Aug 4, 9:12 PM EDT, 1 hour 4 minutes before

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Local storm report, Aug 4, 9:33 PM EDT, 43 minutes before

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Local storm report, Aug 4, 9:44 PM EDT, 32 minutes before

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Local storm report, Aug 4, 9:47 PM EDT, 29 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 4, 8:08 PM EDT	Severe Thunderstorm Warning	LWX	Fauquier, Rappahannock, Warren	52 min
Aug 4, 8:44 PM EDT	Severe Thunderstorm Warning	LWX	Fairfax, Fauquier, Loudoun, Prince William	30 min
Aug 4, 9:03 PM EDT	Special Marine Warning	LWX		87 min
Aug 4, 9:12 PM EDT	Special Marine Warning	LWX		18 min
Aug 5, 12:30 AM EDT	Special Marine Warning	LWX		45 min
Aug 5, 10:20 AM EDT	Flood Watch	LWX	Albemarle, Amherst, Arlington, Augusta, Clarke, Culpeper and 27 more	11 hr
Aug 5, 1:14 PM EDT	Flash Flood Warning	LWX	Rockingham	3 hr
Aug 5, 1:57 PM EDT	Severe Thunderstorm Warning	LWX	Madison	16 min
Aug 5, 2:13 PM EDT	Areal Flood Warning	LWX	Rockingham	104 min
Aug 5, 2:35 PM EDT	Areal Flood Warning	LWX	Augusta, Nelson	84 min
Aug 5, 3:54 PM EDT	Severe Thunderstorm Warning	LWX	Prince William, City of Manassas, City of Manassas Park	36 min
Aug 5, 3:58 PM EDT	Areal Flood Warning	LWX	Rockingham	3 hr
Aug 5, 4:00 PM EDT	Special Marine Warning	LWX		60 min
Aug 5, 4:56 PM EDT	Special Marine Warning	LWX		44 min
Aug 5, 5:04 PM EDT	Special Marine Warning	LWX		36 min
Aug 5, 5:39 PM EDT	Special Marine Warning	LWX		96 min
Aug 5, 5:42 PM EDT	Areal Flood Warning	LWX	Fairfax	4 hr
Aug 5, 5:47 PM EDT	Special Marine Warning	LWX		58 min
Aug 5, 5:54 PM EDT	Special Marine Warning	LWX		66 min
Aug 5, 6:13 PM EDT	Special Marine Warning	LWX		92 min
Aug 5, 6:51 PM EDT	Special Marine Warning	LWX		84 min
Aug 5, 6:54 PM EDT	Special Marine Warning	LWX		96 min
Aug 5, 6:57 PM EDT	Special Marine Warning	LWX		93 min
Aug 5, 7:35 PM EDT	Special Marine Warning	LWX		85 min
Aug 5, 7:54 PM EDT	Special Marine Warning	LWX		96 min
Aug 4, 8:31 PM EDT	Areal Flood Warning	LWX	Baltimore, City of Baltimore	8 hr
Aug 4, 8:31 PM EDT	Areal Flood Warning	LWX	Baltimore, City of Baltimore	8 hr
Aug 5, 12:37 AM EDT	Severe Thunderstorm Warning	LWX	Howard, Montgomery, Prince George's	17 min
Aug 5, 4:31 PM EDT	Areal Flood Warning	LWX	Allegany, Garrett	3 hr
Aug 5, 4:45 PM EDT	Severe Thunderstorm Warning	LWX	Montgomery, Prince George's	30 min
Aug 5, 4:52 PM EDT	Severe Thunderstorm Warning	LWX	Charles	38 min
Aug 5, 4:53 PM EDT	Flash Flood Warning	LWX	Prince George's	106 min
Aug 5, 5:44 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Baltimore, Howard, City of Baltimore	31 min
Aug 5, 6:08 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	115 min
Aug 5, 6:29 PM EDT	Severe Thunderstorm Warning	LWX	Calvert, Saint Mary's	31 min
Aug 5, 6:39 PM EDT	Areal Flood Warning	LWX	Prince George's	4 hr
Aug 5, 7:08 PM EDT	Areal Flood Warning	LWX	Saint Mary's	2 hr
Aug 5, 1:37 PM EDT	Severe Thunderstorm Warning	LWX	Pendleton	23 min

Nearby

Flash Flood Warnings in Maryland, 2022 Flash Flood Warnings in Virginia, 2022 Every flash flood warning in 2022

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.