Alert archive / Delaware / Flash Flood Warnings in 2025
Flash Flood Warning 45, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 9, 2025, 7:18 PM EDT for New Castle County, Delaware; Delaware County, Pennsylvania. It was in force for 4 hr. 11 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
- Jul 9, 2025, 7:18 PM EDT (23:18 UTC)
- Expired
- Jul 9, 2025, 11:15 PM EDT
- In force
- 4 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties New Castle County, DE, Delaware County, PA
The radar
The Philadelphia radar (KDIX), 101 km from the middle of the area, began a volume at 23:20 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 |
|---|---|---|---|
| Jul 9, 7:40 PM EDT | FLASH FLOOD | 1 W Quarryville, DE | Street and road closures due to flooding with vehicles stranded. |
| Jul 9, 8:00 PM EDT | FLASH FLOOD | Concord Twp, PA | Road flooding with car stranded at Spring Valley Rd and Brinton Lake Rd. |
| Jul 9, 8:00 PM EDT | FLASH FLOOD | Elam, PA | US 202 flooded in Elam. |
| Jul 9, 8:00 PM EDT | FLASH FLOOD | Fairfax, DE | Roadway flooding ongoing in Fairfax. Several roads underwater. Time given in report. |
| Jul 9, 8:05 PM EDT | FLASH FLOOD | Glen Mills, PA | Roadway flooded and vehicles stranded at Baltimore Pike and Brinton Lake Rd. |
| Jul 9, 8:10 PM EDT | FLASH FLOOD | 1 N Wooddale, DE | Creek Rd. at Snuff Mill Rd. closed due to flooding. |
| Jul 9, 8:22 PM EDT | FLASH FLOOD | Chadds Ford Twp, PA | Road flooding with cars stranded at Ring Rd. and Baltimore Pike. |
| Jul 9, 8:24 PM EDT | FLASH FLOOD | Wilmington, DE | Buildings and street flooding in Wilmington. People stranded. |
| Jul 9, 8:38 PM EDT | FLASH FLOOD | Glen Mills, PA | Several public reports of water rescues ongoing in Glens Mills. |
| Jul 9, 9:00 PM EDT | FLASH FLOOD | Hockessin, DE | Hockessin Park is underwater from Mill Creek as shown in video and pictures sent in. |
| Jul 9, 9:30 PM EDT | FLASH FLOOD | Tybrook, DE | The Red Clay Creek at Woodale rose rapidly into flood stage. |
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, 11.3 hours before the alert went out and 185 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
- 647 J/kg
- Mixed-layer CIN
- -65 J/kg
- Mixed-layer LCL
- 836 m above ground
- 0-6 km bulk shear
- 24 kt
- 0-1 km storm-relative helicity
- -8 m²/s²
- 0-3 km storm-relative helicity
- 42 m²/s²
- Significant tornado parameter
- -0.0
- Supercell composite
- -0.0
The text
As transmitted.
058
WGUS51 KPHI 092318
FFWPHI
DEC003-PAC045-100315-
/O.NEW.KPHI.FF.W.0045.250709T2318Z-250710T0315Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
718 PM EDT Wed Jul 9 2025
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Northwestern New Castle County in northern Delaware...
Southwestern Delaware County in southeastern Pennsylvania...
* Until 1115 PM EDT.
* At 718 PM EDT, Doppler radar indicated thunderstorms producing
heavy rain across the warned area. Between 0.5 and 1 inch of rain
has fallen. The expected rainfall rate is 1.5 to 2.5 inches in 1
hour. Additional rainfall amounts of 1 to 2.5 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 may experience flash flooding include...
Wilmington, Newark, Chester, Swarthmore, Elsmere, Newport, Arden,
Talleyville, Elam, Greenville, Concordville and Chelsea.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be aware of your surroundings and do not drive on flooded roads.
&&
LAT...LON 3987 7560 3991 7555 3993 7554 3992 7552
3994 7552 3997 7546 3996 7536 3992 7534
3986 7538 3973 7556 3969 7563 3968 7579
3972 7579 3972 7577 3976 7575 3980 7570
3984 7560
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...1.5-2.5 INCHES IN 1 HOUR
$$
HoeflichThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Jul 8, 9:52 PM EDT | Flood Watch | PHI | Kent, New Castle, Sussex | 26 hr |
| Jul 9, 7:24 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 51 min |
| Jul 9, 7:38 PM EDT | Flash Flood Warning | PHI | New Castle | 4 hr |
| Jul 9, 6:39 PM EDT | Flash Flood Warning | PHI | Chester | 4 hr |
| Jul 9, 7:47 PM EDT | Flash Flood Warning | PHI | Chester, Delaware, Montgomery, Philadelphia | 4 hr |
Nearby
Flash Flood Warnings in Delaware, 2025Flash Flood Warnings in Pennsylvania, 2025Every flash flood warning in 2025
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.