Alert archive / Maryland / Flash Flood Warnings in 2021

Flash Flood Warning 2, NWS Baltimore/Washington

June 3, 2021Baltimore County, Harford County, Maryland

NWS Baltimore/Washington issued this flash flood warning at Jun 3, 2021, 6:29 PM EDT for Baltimore County, Harford County, Maryland. It was in force for 3 hr. 7 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued: Jun 3, 2021, 6:29 PM EDT (22:29 UTC)
Expired: Jun 3, 2021, 9:00 PM EDT
In force: 3 hr
Issued by: NWS Baltimore/Washington
Area: Storm-based polygon
Damage threat: Considerable
Flood severity: None

Counties Baltimore County, MD, Harford County, MD

The radar

The Dover AFB radar (KDOX), 112 km from the middle of the area, began a volume at 22:31 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 was reported inside it

Time	Report	Where	Remark
Jun 3, 7:08 PM EDT	FLASH FLOOD	2 Se Hickory, MD	SWIFT WATER RESCUE ON THOMAS RUN ROAD AT CENTERVILLE WAY.
Jun 3, 7:15 PM EDT	FLASH FLOOD	Bel Air, MD	STREAM GAUGE ON PLUMTREE RUN IN BEL AIR INDICATED WATER ROSE 5 FEET IN LESS THAN TWO HOURS, REACHING MINOR FLOOD AT 6 FEET. THE STREAM GAUGE CRESTED AT 6.7 FEET BEFORE FALLING BACK BELOW MINOR FLOOD STAGE.
Jun 3, 7:15 PM EDT	FLASH FLOOD	Bel Air, MD	STREAM GAUGE ON PLUMTREE RUN IN BEL AIR ROSE 5 FEET IN LESS THAN TWO HOURS, EXCEEDING MINOR FLOOD STAGE.
Jun 3, 7:20 PM EDT	FLASH FLOOD	2 Ese Hickory, MD	SWIFT WATER RESCUE ON THOMAS RUN ROAD AT PROSPECT MILL ROAD.
Jun 3, 7:45 PM EDT	FLASH FLOOD	2 Ssw Churchville, MD	ROUTE 136 NEAR JAMES RUN ROAD CLOSED DUE TO FLOWING WATER FROM BROAD RUN CREEK CROSSING THE ROADWAY.
Jun 3, 7:46 PM EDT	FLASH FLOOD	Bel Air, MD	STREAM GAUGE ON BYNUM RUN IN BEL AIR INDICATED WATER ROSE OVER 8 FEET IN ABOUT TWO HOURS, REACHING MINOR FLOOD AT 9.2 FEET.
Jun 3, 8:16 PM EDT	FLASH FLOOD	2 Wnw Harford, MD	SWIFT WATER RESCUE ON PATTERSON MILL ROAD AT EAST WHEEL ROAD.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Washington/Dulle, VA (KIAD), launched 12:00Z, 10.5 hours before the alert went out and 117 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

The text

As transmitted.

892 
WGUS51 KLWX 032229
FFWLWX
MDC005-025-040400-
/O.NEW.KLWX.FF.W.0002.210603T2229Z-210604T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Baltimore MD/Washington DC
629 PM EDT Thu Jun 3 2021

The National Weather Service in Sterling Virginia has issued a

* Flash Flood Warning for...
  East Central Baltimore County in northern Maryland...
  Northeastern Harford County in northern Maryland...

* Until midnight EDT.

* At 629 PM EDT, Doppler radar and automated rain gauges indicated 
  thunderstorms producing heavy rain across the warned area. Between 
  2 and 3 inches of rain have fallen. Flash flooding is ongoing or 
  expected to begin shortly.

  HAZARD...Life threatening flash flooding. Thunderstorms
           producing flash flooding.

  SOURCE...Doppler radar and automated gauges.

  IMPACT...Life threatening flash flooding of creeks and streams,
           urban areas, highways, streets and underpasses.

* Some locations that may experience flash flooding include...
  Cockeysville...                    Aberdeen...
  Havre De Grace...                  Towson...
  Bel Air South...                   Parkville...
  Bel Air North...                   Carney...
  Perry Hall...                      Timonium...
  Fallston...                        Hampton...
  Kingsville...                      Pleasant Hills...
  Lutherville-Timonium...            Lutherville...
  Darlington...                      Benson...
  Bynum...                           Hickory...

Additional rainfall amounts of 1 to 2 inches are possible in the 
warned area into early this evening.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around, don't drown when encountering flooded roads. Most flood 
deaths occur in vehicles.

A Flash Flood Warning means that flooding is imminent or occurring. 
If you are in the warned area move to higher ground immediately. 
Residents living along streams and creeks should take immediate 
precautions to protect life and property.

&&

LAT...LON 3959 7643 3968 7620 3967 7619 3967 7618
      3966 7618 3965 7616 3964 7616 3962 7615
      3957 7610 3944 7638 3939 7656 3943 7660
      3949 7662

FLASH FLOOD...RADAR AND GAUGE INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE

$$

BKF

1 follow-up statement

116 
WGUS71 KLWX 040100
FFSLWX

Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
900 PM EDT Thu Jun 3 2021

MDC005-025-040110-
/O.CAN.KLWX.FF.W.0002.000000T0000Z-210604T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Baltimore MD-Harford MD-
900 PM EDT Thu Jun 3 2021

...FLASH FLOOD WARNING FOR EAST CENTRAL BALTIMORE AND NORTHEASTERN 
HARFORD COUNTIES HAS BEEN REPLACED WITH A FLOOD WARNING...

LAT...LON 3959 7643 3968 7620 3967 7619 3967 7618
      3966 7618 3965 7616 3964 7616 3962 7615
      3957 7610 3944 7638 3939 7656 3943 7660
      3949 7662

$$

BKF

The office that day

Everything else NWS Baltimore/Washington issued on the same UTC day.

Issued	Product	Office	Counties	Lasted
Jun 3, 8:56 AM EDT	Flash Flood Watch	LWX	Baltimore, Carroll, Cecil, Frederick, Harford, Howard and 2 more	13 hr
Jun 3, 3:14 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Montgomery	46 min
Jun 3, 3:47 PM EDT	Severe Thunderstorm Warning	LWX	Carroll, Frederick, Howard, Montgomery	43 min
Jun 3, 3:50 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Washington	40 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, 4:54 PM EDT	Severe Thunderstorm Warning	LWX	Frederick, Montgomery	36 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, 6:36 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 Warnings in Maryland, 2021 Every flash flood warning 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.