Alert archive / Delaware / Flash Flood Warnings in 2024
Flash Flood Warning 50, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 8, 2024, 5:48 PM EDT for New Castle County, Delaware; Chester County, Pennsylvania. It was in force for 6 hr. 12 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
- Aug 8, 2024, 5:48 PM EDT (21:48 UTC)
- Expired
- Aug 8, 2024, 11:40 PM EDT
- In force
- 6 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties New Castle County, DE, Chester County, PA
The radar
The Philadelphia radar (KDIX), 113 km from the middle of the area, began a volume at 21:48 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 |
|---|---|---|---|
| Aug 8, 6:00 PM EDT | RAIN 2.16 | 1 Nnw Hockessin, DE | Mesonet station CW9699 Kennett Square. |
| Aug 8, 6:16 PM EDT | FLASH FLOOD | Toughkenamon, PA | Social media photo of about a foot of water on the roadway in Toughkenamon. |
| Aug 8, 6:24 PM EDT | FLASH FLOOD | 2 S Springdell, PA | Report from mPING: Street/road flooding; Street/road closed; Vehicles stranded. |
| Aug 8, 6:29 PM EDT | FLOOD | 1 Ne Caln Twp, PA | Flooding on US 30 eastbound between Exit: PA 340 - THORNDALE and Exit: US 322 - MANOR AVE. There is a lane restriction. |
| Aug 8, 6:30 PM EDT | FLASH FLOOD | Kennett Square, PA | Pictures show several roads in the Kennett Square area blocked due to high water. Time estimated. |
| Aug 8, 7:41 PM EDT | RAIN 3.16 | 1 Ne South Coatesville, PA | Mesonet station EW3013 Coatesville. |
| Aug 8, 7:45 PM EDT | RAIN 3.37 | 1 Ne Kaolin, PA | Mesonet station FW8290 Kennett Square. |
| Aug 8, 8:15 PM EDT | FLASH FLOOD | Coatesville, PA | Severel water rescues due to vehicles stuck in high water in Coatesville. Time estimated. |
| Aug 8, 9:30 PM EDT | RAIN 2.11 | West Bradford Twp, PA | Mesonet station EW9576 Downingtown. |
| Aug 8, 9:30 PM EDT | RAIN 3.39 | 1 Ne Kaolin, PA | Mesonet station FW8290 Kennett Square. |
| Aug 8, 9:30 PM EDT | RAIN 4.01 | 1 Nnw Hockessin, DE | Mesonet station CW9699 Kennett Square. |
| Aug 8, 9:31 PM EDT | RAIN 4.53 | 1 Ne South Coatesville, PA | Mesonet station EW3013 Coatesville. |
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, 9.8 hours before the alert went out and 176 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
- 243 J/kg
- Mixed-layer CIN
- -3 J/kg
- Mixed-layer LCL
- 494 m above ground
- 0-6 km bulk shear
- 8 kt
- 0-1 km storm-relative helicity
- 115 m²/s²
- 0-3 km storm-relative helicity
- 158 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.0
The text
As transmitted.
721
WGUS51 KPHI 082148
FFWPHI
DEC003-PAC029-090200-
/O.NEW.KPHI.FF.W.0050.240808T2148Z-240809T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
548 PM EDT Thu Aug 8 2024
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Northwestern New Castle County in northern Delaware...
South Central Chester County in southeastern Pennsylvania...
* Until 1000 PM EDT.
* At 548 PM EDT, Doppler radar indicated showers and isolated
thunderstorms producing very heavy rain across the warned area.
Between 0.5 and 1.5 inches of rain have fallen. The expected
rainfall rate is 2 to 3 inches in 1 hour. 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 may experience flash flooding include...
Coatesville, Downingtown, Kennett Square, Marshallton, Landenberg,
Hockessin, North Star, South Coatesville, Avondale, Modena,
Toughkenamon and Thorndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4002 7577 4001 7563 3992 7563 3982 7563
3981 7568 3975 7575 3972 7575 3972 7578
3983 7582 3999 7589
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...2-3 INCHES IN 1 HOUR
$$
Gorse4 follow-up statements
801
WGUS71 KPHI 082238
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
638 PM EDT Thu Aug 8 2024
DEC003-PAC029-090200-
/O.CON.KPHI.FF.W.0050.000000T0000Z-240809T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Chester PA-
638 PM EDT Thu Aug 8 2024
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING FOR NORTHWESTERN NEW CASTLE AND SOUTH CENTRAL CHESTER
COUNTIES...
At 638 PM EDT, trained weather spotters reported some streams and
nearby roads are flooded with some roads flooded that typically do
not flood in the Landenberg Pennsylvania area. Between 2 and 3
inches of rain have fallen. The expected rainfall rate is 2 to 3
inches in 1 hour. Flash flooding is already occurring.
HAZARD...Life threatening flash flooding caused by thunderstorms.
SOURCE...Trained spotters reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
Some locations that may experience flash flooding include...
Coatesville, Downingtown, Kennett Square, Marshallton, Landenberg,
Hockessin, North Star, South Coatesville, Avondale, Modena,
Toughkenamon and Thorndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4002 7577 4001 7563 3992 7563 3982 7563
3981 7568 3975 7575 3972 7575 3972 7578
3983 7582 3999 7589
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...2-3 INCHES IN 1 HOUR
$$
Gorse526
WGUS71 KPHI 090021
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
821 PM EDT Thu Aug 8 2024
DEC003-PAC029-090200-
/O.CON.KPHI.FF.W.0050.000000T0000Z-240809T0200Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Chester PA-
821 PM EDT Thu Aug 8 2024
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING FOR NORTHWESTERN NEW CASTLE AND SOUTH CENTRAL CHESTER
COUNTIES...
At 821 PM EDT, trained weather spotters reported significant street
flooding from Landenberg to Avondale and also in the Coatesville
areas. Between 2 and 5 inches of rain have fallen. The expected
rainfall rate is 2 to 3 inches in 1 hour. Flash flooding is already
occurring.
HAZARD...Life threatening flash flooding caused by thunderstorms.
SOURCE...Trained spotters reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
Some locations that may experience flash flooding include...
Coatesville, Downingtown, Kennett Square, Marshallton, Landenberg,
Hockessin, North Star, South Coatesville, Avondale, Modena,
Toughkenamon and Thorndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
&&
LAT...LON 4002 7577 4001 7563 3992 7563 3982 7563
3981 7568 3975 7575 3972 7575 3972 7578
3983 7582 3999 7589
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...2-3 INCHES IN 1 HOUR
$$
Gorse012
WGUS51 KPHI 090121
FFWPHI
DEC003-PAC029-090400-
/O.EXT.KPHI.FF.W.0050.000000T0000Z-240809T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
921 PM EDT Thu Aug 8 2024
The National Weather Service in Mount Holly has extended the
* Flash Flood Warning for...
Northwestern New Castle County in northern Delaware...
South Central Chester County in southeastern Pennsylvania...
* Until midnight EDT tonight.
* At 921 PM EDT, several areas continue to experience flooding in
the warned area. There is also ongoing flooding along the White
Clay Creek at Strickersville and also on the Red Clay Creek at
Kennet Square. Between 3 and 6 inches of rain have fallen. Flash
flooding is already occurring.
HAZARD...Life threatening flash flooding caused by
thunderstorms.
SOURCE...Trained spotters reported.
IMPACT...Life threatening flash flooding of creeks and streams,
urban areas, highways, streets, and underpasses.
* Some locations that may experience flash flooding include...
Coatesville, Downingtown, Kennett Square, Marshallton, Landenberg,
Hockessin, North Star, South Coatesville, Avondale, Modena,
Toughkenamon and Thorndale.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
&&
LAT...LON 4002 7577 4001 7563 3992 7563 3982 7563
3981 7568 3975 7575 3972 7575 3972 7578
3983 7582 3999 7589
FLASH FLOOD...OBSERVED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
$$
Gorse410
WGUS71 KPHI 090340
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1140 PM EDT Thu Aug 8 2024
DEC003-PAC029-090350-
/O.CAN.KPHI.FF.W.0050.000000T0000Z-240809T0400Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Chester PA-
1140 PM EDT Thu Aug 8 2024
...FLASH FLOOD WARNING FOR NORTHWESTERN NEW CASTLE AND SOUTH CENTRAL
CHESTER COUNTIES HAS BEEN REPLACED WITH A FLOOD WARNING...
&&
LAT...LON 4002 7577 4001 7563 3992 7563 3982 7563
3981 7568 3975 7575 3972 7575 3972 7578
3983 7582 3999 7589
$$
SFJThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Aug 8, 3:17 AM EDT | Rip Current Statement | PHI | Sussex | 40 hr |
| Aug 8, 2:20 PM EDT | Coastal Flood Advisory | PHI | New Castle, Sussex | 40 hr |
| Aug 8, 2:20 PM EDT | High Surf Advisory | PHI | Sussex | 29 hr |
| Aug 8, 3:13 PM EDT | Wind Advisory | PHI | Kent, New Castle, Sussex | 27 hr |
| Aug 8, 3:46 PM EDT | Flash Flood Warning | PHI | New Castle | 7 hr |
| Aug 8, 5:26 PM EDT | River Flood Warning | PHI | New Castle | 14 hr |
| Aug 8, 5:26 PM EDT | River Flood Warning | PHI | New Castle | 6 hr |
| Aug 8, 6:04 PM EDT | Flood Watch | PHI | New Castle | 24 hr |
| Aug 8, 6:59 PM EDT | Tornado Warning | PHI | New Castle | 31 min |
Nearby
Flash Flood Warnings in Delaware, 2024Flash Flood Warnings in Pennsylvania, 2024Every flash flood warning in 2024
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.