Alert archive / Delaware / Flash Flood Warnings in 2021
Flash Flood Warning 36, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 15, 2021, 12:36 AM EDT for Kent County, Delaware. 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 outline as issued.
The facts
- Issued
- Aug 15, 2021, 12:36 AM EDT (04:36 UTC)
- Expired
- Aug 15, 2021, 3:30 AM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
County Kent County, DE
The radar
The Dover AFB radar (KDOX), 17 km from the middle of the area, began a volume at 04:39 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, 4.6 hours before the alert went out and 108 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
- 1575 J/kg
- Mixed-layer CIN
- -47 J/kg
- Mixed-layer LCL
- 1189 m above ground
- 0-6 km bulk shear
- 15 kt
- 0-1 km storm-relative helicity
- -3 m²/s²
- 0-3 km storm-relative helicity
- 28 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
625
WGUS51 KPHI 150436
FFWPHI
DEC001-150730-
/O.NEW.KPHI.FF.W.0036.210815T0436Z-210815T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1236 AM EDT Sun Aug 15 2021
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Southwestern Kent County in central Delaware...
* Until 330 AM EDT.
* At 1236 AM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 2 and 3 inches of rain
have fallen. Additional rainfall amounts of 1 to 2 inches are
possible in the warned area. Flash flooding is ongoing or expected
to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
* Some locations that will experience flash flooding include...
Harrington, Andrewsville, and Farmington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Motorists should not attempt to drive around barricades or drive
cars through flooded areas.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 3890 7573 3893 7567 3894 7559 3893 7556
3893 7554 3891 7551 3888 7552 3885 7555
3884 7559 3884 7561 3884 7562 3883 7572
3886 7572 3888 7573
FLASH FLOOD...RADAR INDICATED
$$
BAH2 follow-up statements
862
WGUS71 KPHI 150529
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
129 AM EDT Sun Aug 15 2021
DEC001-150730-
/O.CON.KPHI.FF.W.0036.000000T0000Z-210815T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-
129 AM EDT Sun Aug 15 2021
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM EDT EARLY THIS
MORNING FOR SOUTHWESTERN KENT COUNTY...
At 129 AM EDT, Doppler radar indicated thunderstorms producing heavy
rain across the warned area. Between 2.5 and 3.5 inches of rain have
fallen. Additional rainfall amounts of 0.5 to 1 inch are possible in
the warned area. Flash flooding is ongoing or expected to begin
shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that will experience flash flooding include...
Harrington, Andrewsville, and Farmington.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3890 7573 3893 7567 3894 7559 3893 7556
3893 7554 3891 7551 3888 7552 3885 7555
3884 7559 3884 7561 3884 7562 3883 7572
3886 7572 3888 7573
FLASH FLOOD...RADAR INDICATED
$$
BAH187
WGUS71 KPHI 150721
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
321 AM EDT Sun Aug 15 2021
DEC001-150731-
/O.EXP.KPHI.FF.W.0036.000000T0000Z-210815T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Kent DE-
321 AM EDT Sun Aug 15 2021
...FLASH FLOOD WARNING WILL EXPIRE AT 330 AM EDT EARLY THIS MORNING
FOR SOUTHWESTERN KENT COUNTY...
The heavy rain has ended. Flooding is no longer expected to pose a
threat. Please continue to heed remaining road closures.
LAT...LON 3890 7573 3893 7567 3894 7559 3893 7556
3893 7554 3891 7551 3888 7552 3885 7555
3884 7559 3884 7561 3884 7562 3883 7572
3886 7572 3888 7573
$$
BAHThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 14, 11:34 PM EDT | Areal Flood Advisory | PHI | Kent | 116 min |
Nearby
Flash Flood Warnings in Delaware, 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.