Alert archive / Maryland / Flash Flood Watches in 2021

Flash Flood Watch 1, NWS Baltimore/Washington

June 3, 20218 counties in Maryland

NWS Baltimore/Washington issued this flash flood watch at Jun 3, 2021, 8:56 AM EDT for 8 counties in Maryland. It took effect at Jun 3, 2021, 3:00 PM EDT. It was in force for 7 hr.

The area

The counties it named.

The facts

Issued: Jun 3, 2021, 8:56 AM EDT (12:56 UTC)
In effect from: Jun 3, 2021, 3:00 PM EDT
Expired: Jun 3, 2021, 10:00 PM EDT
In force: 7 hr
Issued by: NWS Baltimore/Washington
Flood severity: None

Counties Baltimore County, MD, Carroll County, MD, Cecil County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Montgomery County, MD

The radar

The Sterling radar (KLWX), 79 km from the middle of the area, began a volume at 12:58 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, 0.9 hours before the alert went out and 75 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: 73 J/kg
Mixed-layer CIN: -52 J/kg
Mixed-layer LCL: 511 m above ground
0-6 km bulk shear: 39 kt
0-1 km storm-relative helicity: 116 m²/s²
0-3 km storm-relative helicity: 118 m²/s²
Significant tornado parameter: 0.0
Supercell composite: 0.2

Open this sounding in Storm Lab

What forecasters said that day

The local office's own words before this flash flood watch 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 watch went out at Jun 3, 6:32 AM EDT, 2 hours 24 minutes earlier.

Area forecast discussion, Jun 3, 6:32 AM EDT, 2 hours 24 minutes before

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Hazardous weather outlook, Jun 3, 5:29 AM EDT, 3 hours 27 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
Jun 3, 3:10 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Frederick, City of Winchester	50 min
Jun 3, 3:14 PM EDT	Severe Thunderstorm Warning	LWX	Loudoun	46 min
Jun 3, 3:41 PM EDT	Special Marine Warning	LWX		2 hr
Jun 3, 3:50 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Loudoun	40 min
Jun 3, 3:56 PM EDT	Severe Thunderstorm Warning	LWX	Albemarle, Culpeper, Greene, Madison, Orange, Page and 2 more	49 min
Jun 3, 4:08 PM EDT	Severe Thunderstorm Warning	LWX	Clarke, Fauquier, Loudoun	52 min
Jun 3, 4:20 PM EDT	Special Marine Warning	LWX		85 min
Jun 3, 4:45 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Madison, Orange	45 min
Jun 3, 4:48 PM EDT	Special Marine Warning	LWX		87 min
Jun 3, 4:54 PM EDT	Severe Thunderstorm Warning	LWX	Loudoun	36 min
Jun 3, 5:08 PM EDT	Special Marine Warning	LWX		2 hr
Jun 3, 5:19 PM EDT	Severe Thunderstorm Warning	LWX	Culpeper, Fauquier, Orange, Prince William, Spotsylvania, Stafford	41 min
Jun 3, 5:32 PM EDT	Severe Thunderstorm Warning	LWX	Orange, Spotsylvania	43 min
Jun 3, 5:45 PM EDT	Special Marine Warning	LWX		106 min
Jun 3, 6:59 PM EDT	Special Marine Warning	LWX		56 min
Jun 3, 3:47 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick, Howard, Montgomery	43 min
Jun 3, 4:12 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore	33 min
Jun 3, 4:20 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Carroll, Howard, City of Baltimore	40 min
Jun 3, 4:43 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Cecil, Harford, City of Baltimore	47 min
Jun 3, 4:51 PM EDT	Tornado Warning	LWX	Baltimore, Harford	9 min
Jun 3, 4:58 PM EDT	Areal Flood Warning	LWX	Baltimore, Harford	6 hr
Jun 3, 4:59 PM EDT	Tornado Warning	LWX	Baltimore, Harford	16 min
Jun 3, 5:26 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Cecil, Harford	49 min
Jun 3, 5:27 PM EDT	Severe Thunderstorm Warning	LWX	Howard, Montgomery	33 min
Jun 3, 5:55 PM EDT	Areal Flood Warning	LWX	Baltimore, Harford	34 min
Jun 3, 6:03 PM EDT	Severe Thunderstorm Warning	LWX	Anne Arundel, Howard, Montgomery, Prince George's	28 min
Jun 3, 6:14 PM EDT	Severe Thunderstorm Warning	LWX	Cecil, Harford	34 min
Jun 3, 6:29 PM EDT	Flash Flood Warning Considerable damage threat	LWX	Baltimore, Harford	3 hr
Jun 3, 6:36 PM EDT	Severe Thunderstorm Warning	LWX	Baltimore, Harford	39 min
Jun 3, 6:46 PM EDT	Areal Flood Warning	LWX	Cecil	4 hr
Jun 3, 6:53 PM EDT	Tornado Warning	LWX	Harford	10 min

Nearby

Flash Flood Watches in Maryland, 2021 Every flash flood watch in 2021

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.