Alert archive / Pennsylvania / Flash Flood Warnings in 2025
Flash Flood Warning 2, NWS Philadelphia/Mount Holly
NWS Philadelphia/Mount Holly issued this flash flood warning at May 3, 2025, 7:32 PM EDT for New Castle County, Delaware; Chester County, Delaware County, Pennsylvania. It was in force for 3 hr. 2 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
- May 3, 2025, 7:32 PM EDT (23:32 UTC)
- Expired
- May 3, 2025, 10:32 PM EDT
- In force
- 3 hr
- Issued by
- NWS Philadelphia/Mount Holly
- Area
- Storm-based polygon
- Flood severity
- None
Counties New Castle County, DE, Chester County, PA, Delaware County, PA
The radar
The Philadelphia radar (KDIX), 96 km from the middle of the area, began a volume at 23:31 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 |
|---|---|---|---|
| May 3, 8:31 PM EDT | FLOOD | 1 Ene Broomall, PA | Flooding on I-476 northbound between .7 miles north of Exit 9: PA 3 - BROOMALL/UPPER DARBY and Exit 13: US 30 - ST DAVIDS/VILLANOVA. There is a lane restriction. |
| May 3, 8:34 PM EDT | FLOOD | 1 Nne Nether Providence, PA | Flooding on I-476 southbound between Exit 3: SWARTHMORE/MEDIA and Exit 1: MACDADE BLVD. There is a traffic disruption. |
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, 11.5 hours before the alert went out and 188 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
- 77 J/kg
- Mixed-layer CIN
- -174 J/kg
- Mixed-layer LCL
- 1072 m above ground
- 0-6 km bulk shear
- 30 kt
- 0-1 km storm-relative helicity
- 34 m²/s²
- 0-3 km storm-relative helicity
- 90 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- -0.0
The text
As transmitted.
368
WGUS51 KPHI 032332
FFWPHI
DEC003-PAC029-045-040330-
/O.NEW.KPHI.FF.W.0002.250503T2332Z-250504T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
732 PM EDT Sat May 3 2025
The National Weather Service in Mount Holly has issued a
* Flash Flood Warning for...
Northern New Castle County in northern Delaware...
Southeastern Chester County in southeastern Pennsylvania...
Delaware County in southeastern Pennsylvania...
* Until 1130 PM EDT.
* At 732 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 0.5 to 1 inch in 1 hour.
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 may experience flash flooding include...
Wilmington, Newark, Chester, Westtown, Swarthmore, Elsmere,
Kennett Square, Newport, Arden, Talleyville, Elam and Concordville.
This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 0 and 12.
Interstate 95 in Pennsylvania between mile markers 0 and 7.
Interstate 95 in Delaware between mile markers 5 and 23.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4001 7543 4003 7540 4003 7536 3992 7527
3991 7528 3980 7541 3980 7542 3979 7543
3966 7561 3965 7567 3968 7579 3972 7579
3972 7583 3975 7585
FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5-1 INCH IN 1 HOUR
$$
MPS2 follow-up statements
103
WGUS71 KPHI 040128
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
928 PM EDT Sat May 3 2025
DEC003-PAC029-045-040330-
/O.CON.KPHI.FF.W.0002.000000T0000Z-250504T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Chester PA-Delaware PA-
928 PM EDT Sat May 3 2025
...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 1130 PM EDT THIS
EVENING FOR NORTHERN NEW CASTLE, SOUTHEASTERN CHESTER AND DELAWARE
COUNTIES...
At 928 PM EDT, Doppler radar indicated thunderstorms produced heavy
rain across the warned area earlier this evening, but rain has since
ended. Between 1 and 2 inches of rain have fallen. Flash flooding is
ongoing or expected to begin shortly.
HAZARD...Flash flooding caused by thunderstorms.
SOURCE...Radar.
IMPACT...Flooding of small creeks and streams, urban areas,
highways, streets, and underpasses as well as other
drainage and low lying areas.
Some locations that may experience flash flooding include...
Wilmington, Newark, Chester, Westtown, Swarthmore, Elsmere,
Kennett Square, Newport, Arden, Talleyville, Elam and Concordville.
This includes the following highways...
Interstate 476 in Pennsylvania between mile markers 0 and 12.
Interstate 95 in Pennsylvania between mile markers 0 and 7.
Interstate 95 in Delaware between mile markers 5 and 23.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Turn around...don't drown when encountering flooded roads. Most
flood deaths occur in vehicles.
Be especially cautious at night when it is harder to recognize the
dangers of flooding.
Be aware of your surroundings and do not drive on flooded roads.
Please report observed flooding to local emergency services or law
enforcement and request they pass this information to the National
Weather Service when you can do so safely.
&&
LAT...LON 4001 7543 4003 7540 4003 7536 3992 7527
3991 7528 3980 7541 3980 7542 3979 7543
3966 7561 3965 7567 3968 7579 3972 7579
3972 7583 3975 7585
FLASH FLOOD...RADAR INDICATED
$$
MPS943
WGUS71 KPHI 040232
FFSPHI
Flash Flood Statement
National Weather Service Mount Holly NJ
1032 PM EDT Sat May 3 2025
DEC003-PAC029-045-040242-
/O.CAN.KPHI.FF.W.0002.000000T0000Z-250504T0330Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
New Castle DE-Chester PA-Delaware PA-
1032 PM EDT Sat May 3 2025
...FLASH FLOOD WARNING IS CANCELLED FOR NORTHERN NEW CASTLE,
SOUTHEASTERN CHESTER AND DELAWARE COUNTIES...
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 4001 7543 4003 7540 4003 7536 3992 7527
3991 7528 3980 7541 3980 7542 3979 7543
3966 7561 3965 7567 3968 7579 3972 7579
3972 7583 3975 7585
$$
RCMThe office that day
Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| May 3, 6:16 PM EDT | Severe Thunderstorm Warning | PHI | New Castle | 44 min |
| May 3, 4:38 PM EDT | Severe Thunderstorm Warning | PHI | Bucks | 52 min |
| May 3, 7:34 PM EDT | Severe Thunderstorm Warning | PHI | Bucks, Delaware, Montgomery, Philadelphia | 41 min |
Nearby
Flash Flood Warnings in Pennsylvania, 2025Flash Flood Warnings in Delaware, 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.