Alert archive / Maryland / Flash Flood Warnings in 2021
Flash Flood Warning 46, NWS Baltimore/Washington
NWS Baltimore/Washington issued this flash flood warning at Aug 18, 2021, 11:59 PM EDT for Cecil 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 outline as issued.
The facts
- Issued
- Aug 18, 2021, 11:59 PM EDT (03:59 UTC)
- Expired
- Aug 19, 2021, 2:04 AM EDT
- In force
- 2 hr
- Issued by
- NWS Baltimore/Washington
- Area
- Storm-based polygon
- Damage threat
- Considerable
- Flood severity
- None
County Cecil County, MD
The radar
The Dover AFB radar (KDOX), 107 km from the middle of the area, began a volume at 03:58 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 00:00Z, 4.0 hours before the alert went out and 145 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.
- Mixed-layer CAPE
- 1288 J/kg
- Mixed-layer CIN
- -8 J/kg
- Mixed-layer LCL
- 1100 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 126 m²/s²
- 0-3 km storm-relative helicity
- 171 m²/s²
- Significant tornado parameter
- 0.6
- Supercell composite
- 5.9
The text
As transmitted.
551
WGUS51 KLWX 190359
FFWLWX
MDC015-190700-
/O.NEW.KLWX.FF.W.0046.210819T0359Z-210819T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Baltimore MD/Washington DC
1159 PM EDT Wed Aug 18 2021
The National Weather Service in Sterling Virginia has issued a
* Flash Flood Warning for...
Cecil County in northeastern Maryland...
* Until 300 AM EDT.
* At 1159 PM EDT, Doppler radar indicated heavy rain across the
warned area. Between 1.5 and 2 inches of rain have fallen. The
expected rainfall rate is 1 to 2 inches in 1 hour. Flash flooding
is ongoing or expected to begin shortly.
HAZARD...Life threatening flash flooding. Heavy rain producing
flash flooding.
SOURCE...Radar.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets and underpasses.
* Some locations that will experience flash flooding include...
Calvert... Rising Sun...
Farmington... Zion...
West Nottingham... Lombard...
Blake...
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around, don't drown when encountering flooded roads. Most flood
deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 3972 7602 3972 7590 3970 7589 3968 7592
3966 7599 3963 7605 3963 7610 3966 7611
3970 7606 3972 7603
FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL...1-2 INCHES IN 1 HOUR
$$
BRO1 follow-up statement
019
WGUS71 KLWX 190604
FFSLWX
Flash Flood Statement
National Weather Service Baltimore MD/Washington DC
204 AM EDT Thu Aug 19 2021
MDC015-190614-
/O.CAN.KLWX.FF.W.0046.000000T0000Z-210819T0700Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Cecil MD-
204 AM EDT Thu Aug 19 2021
...FLASH FLOOD WARNING IS CANCELLED FOR CECIL COUNTY...
Flood waters have receded. The heavy rain has ended. Flooding is no
longer expected to pose a threat. Please continue to heed remaining
road closures.
LAT...LON 3972 7602 3972 7590 3970 7589 3968 7592
3966 7599 3963 7605 3963 7610 3966 7611
3970 7606 3972 7603
$$
BROThe office that day
Everything else NWS Baltimore/Washington issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 18, 8:57 PM EDT | Tornado Warning | LWX | Baltimore | 22 min |
| Aug 19, 2:11 PM EDT | Flash Flood Watch | LWX | Allegany, Anne Arundel, Baltimore, Calvert, Charles, Howard and 4 more | 28 hr |
Nearby
Flash Flood Warnings in Maryland, 2021Every 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; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.