Alert archive / Maryland / Flash Flood Warnings in 2022

Flash Flood Warning 22, NWS Baltimore/Washington

July 2, 2022Montgomery County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jul 2, 2022, 10:31 PM EDT for Montgomery County, Maryland. It was in force for 3 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: Jul 2, 2022, 10:31 PM EDT (02:31 UTC)
Expired: Jul 3, 2022, 1:19 AM EDT
In force: 3 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Flood severity: None

County Montgomery County, MD

The radar

The Sterling radar (KLWX), 30 km from the middle of the area, began a volume at 02:34 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 00:00Z, 2.5 hours before the alert went out and 27 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: 2592 J/kg
Mixed-layer CIN: -5 J/kg
Mixed-layer LCL: 1110 m above ground
0-6 km bulk shear: 16 kt
0-1 km storm-relative helicity: 23 m²/s²
0-3 km storm-relative helicity: 43 m²/s²
Significant tornado parameter: 0.1
Supercell composite: 0.8

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 Jul 2, 9:58 PM EDT, 33 minutes earlier.

Area forecast discussion, Jul 2, 9:58 PM EDT, 33 minutes before

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Hazardous weather outlook, Jul 2, 10:03 PM EDT, 28 minutes before

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In the hours before

Local storm report, Jul 2, 9:38 PM EDT, 53 minutes before

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Local storm report, Jul 2, 9:41 PM EDT, 50 minutes before

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Local storm report, Jul 2, 10:10 PM EDT, 21 minutes before

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Local storm report, Jul 2, 10:21 PM EDT, 10 minutes before

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Local storm report, Jul 2, 10:27 PM EDT, 4 minutes before

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Local storm report, Jul 2, 10:31 PM EDT, 0 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
Jul 2, 8:10 PM EDT	Special Marine Warning	LWX		95 min
Jul 2, 9:01 PM EDT	Flash Flood Warning	LWX	Arlington, Fairfax	6 hr
Jul 2, 9:37 PM EDT	Special Marine Warning	LWX		63 min
Jul 2, 11:00 PM EDT	Flash Flood Warning	LWX	Loudoun	3 hr
Jul 3, 12:25 AM EDT	Special Marine Warning	LWX		2 hr
Jul 3, 2:46 AM EDT	Areal Flood Warning	LWX	Arlington, Fairfax	6 hr
Jul 3, 2:48 AM EDT	Areal Flood Warning	LWX	Arlington	6 hr
Jul 2, 8:07 PM EDT	Areal Flood Warning	LWX	Cecil	5 hr
Jul 2, 8:34 PM EDT	Flash Flood Warning	LWX	Baltimore, City of Baltimore	3 hr
Jul 2, 9:13 PM EDT	Severe Thunderstorm Warning	LWX	Cecil	47 min
Jul 2, 9:16 PM EDT	Tornado Warning	LWX	Cecil	16 min
Jul 2, 10:52 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Montgomery	3 hr
Jul 2, 11:16 PM EDT	Areal Flood Warning	LWX	Baltimore, City of Baltimore	3 hr
Jul 3, 12:52 AM EDT	Flash Flood Warning	LWX	Prince George's	116 min
Jul 3, 1:17 AM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Prince George's	43 min
Jul 3, 1:19 AM EDT	Areal Flood Warning	LWX	Montgomery	3 hr
Jul 3, 1:48 AM EDT	Areal Flood Warning	LWX	Montgomery	3 hr

Nearby

Flash Flood Warnings in Maryland, 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.