Alert archive / Pennsylvania / Flash Flood Warnings in 2025

Flash Flood Warning 15, NWS Philadelphia/Mount Holly

May 30, 2025Burlington County, Camden County, Gloucester County, New Jersey; 5 counties in Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at May 30, 2025, 11:36 PM EDT for Burlington County, Camden County, Gloucester County, New Jersey; 5 counties in Pennsylvania. It was in force for 4 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 30, 2025, 11:36 PM EDT (03:36 UTC)
Expired
May 31, 2025, 3:45 AM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Burlington County, NJ, Camden County, NJ, Gloucester County, NJ, Bucks County, PA, Chester County, PA, Delaware County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 62 km from the middle of the area, began a volume at 03:39 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.

What was reported inside it

TimeReportWhereRemark
May 31, 12:05 AM EDTFLASH FLOOD1 Ene Eastwick, PAPicture of a car that spun out in heavy rain that ended up stuck in flood waters. Time estimated.
May 31, 1:00 AM EDTFLASH FLOOD1 Ssw Eddington, PAReport of Station Avenue closed in Bensalem with vehicles stuck. Time given in report.

Local storm reports filed while the alert was in force, from inside its polygon or its counties.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 3.6 hours before the alert went out and 212 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.

Skew-T log-pSkew-T log-p diagram, Brookhaven, NY at 00:00Z on 2025-05-31Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Brookhaven, NY at 00:00Z on 2025-05-31The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
1 J/kg
Mixed-layer CIN
No buoyant parcel
Mixed-layer LCL
558 m above ground
0-6 km bulk shear
36 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
101 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

842 
WGUS51 KPHI 310336
FFWPHI
NJC005-007-015-PAC017-029-045-091-101-310745-
/O.NEW.KPHI.FF.W.0015.250531T0336Z-250531T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1136 PM EDT Fri May 30 2025

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northwestern Burlington County in southern New Jersey...
  Northwestern Camden County in southern New Jersey...
  North Central Gloucester County in southern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...
  East Central Chester County in southeastern Pennsylvania...
  Northeastern Delaware County in southeastern Pennsylvania...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...

* Until 345 AM EDT.

* At 1136 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Up to 0.5 inches of rain have 
  fallen. The expected rainfall rate is 0.5 to 1.5 inches 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...
  Philadelphia, Camden, Gloucester City, Cherry Hill, Bensalem, 
  Mount Laurel, Norristown, Willingboro, Deptford, West Deptford, 
  West Norriton and East Norriton.

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 4012 7550 4015 7543 4014 7534 4018 7517
      4017 7510 4017 7493 4016 7490 4014 7484
      4012 7479 4010 7479 4005 7480 3997 7487
      3988 7499 3979 7515 3980 7521 3982 7519
      3992 7535 3995 7552

FLASH FLOOD...RADAR INDICATED
EXPECTED RAINFALL RATE...0.5-1.5 INCHES IN 1 HOUR

$$

Hoeflich
2 follow-up statements
181 
WGUS71 KPHI 310540
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
140 AM EDT Sat May 31 2025

NJC005-007-015-PAC017-029-045-091-101-310745-
/O.CON.KPHI.FF.W.0015.000000T0000Z-250531T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Camden NJ-Gloucester NJ-Bucks PA-Chester PA-
Delaware PA-Montgomery PA-Philadelphia PA-
140 AM EDT Sat May 31 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 345 AM EDT EARLY THIS 
MORNING FOR NORTHWESTERN BURLINGTON, NORTHWESTERN CAMDEN, NORTH 
CENTRAL GLOUCESTER, SOUTHEASTERN BUCKS, EAST CENTRAL CHESTER, 
NORTHEASTERN DELAWARE, SOUTHEASTERN MONTGOMERY AND PHILADELPHIA 
COUNTIES...

At 140 AM EDT, trained weather spotters reported heavy rain with 
road closures in Bensalem with cars stuck. Between 1 and 2 inches of 
rain have fallen. The expected rainfall rate is 0.5 inches in 1 
hour. Additional rainfall amounts up to 1 inch are possible in the 
warned area. Flash flooding is already occurring.

HAZARD...Flash flooding caused by heavy rain.

SOURCE...Trained spotters reported.

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...
  Philadelphia, Camden, Gloucester City, Cherry Hill, Bensalem, 
  Mount Laurel, Norristown, Willingboro, Deptford, West Deptford, 
  West Norriton and East Norriton.

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 4012 7550 4015 7543 4014 7534 4018 7517
      4017 7510 4017 7493 4016 7490 4014 7484
      4012 7479 4010 7479 4005 7480 3997 7487
      3988 7499 3979 7515 3980 7521 3982 7519
      3992 7535 3995 7552

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...0.5 INCHES IN 1 HOUR

$$

Hoeflich
439 
WGUS71 KPHI 310736
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
336 AM EDT Sat May 31 2025

NJC005-007-015-PAC017-029-045-091-101-310746-
/O.EXP.KPHI.FF.W.0015.000000T0000Z-250531T0745Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Camden NJ-Gloucester NJ-Bucks PA-Chester PA-
Delaware PA-Montgomery PA-Philadelphia PA-
336 AM EDT Sat May 31 2025

...FLASH FLOOD WARNING WILL EXPIRE AT 345 AM EDT EARLY THIS MORNING 
FOR NORTHWESTERN BURLINGTON, NORTHWESTERN CAMDEN, NORTH CENTRAL 
GLOUCESTER, SOUTHEASTERN BUCKS, EAST CENTRAL CHESTER, NORTHEASTERN 
DELAWARE, SOUTHEASTERN MONTGOMERY AND PHILADELPHIA COUNTIES...

The heavy rain has ended. While the threat for widespread flooding 
has ended, some creeks and streams continue to slowly rise. More 
targeted flood warnings may be needed. Have a way to receive 
warnings and please continue to heed remaining road closures.

A Flood Watch remains in effect until 800 AM EDT for portions of 
northern Delaware and Pennsylvania.

A Flood Watch remains in effect until 800 AM EDT for portions of 
central, northern, northwest, and southern New Jersey.

&&

LAT...LON 4012 7550 4015 7543 4014 7534 4018 7517
      4017 7510 4017 7493 4016 7490 4014 7484
      4012 7479 4010 7479 4005 7480 3997 7487
      3988 7499 3979 7515 3980 7521 3982 7519
      3992 7535 3995 7552

$$

Hoeflich

The office that day

Everything else NWS Philadelphia/Mount Holly issued on the same UTC day.

IssuedProductOfficeCountiesLasted
May 30, 9:04 PM EDTWind AdvisoryPHIAtlantic, Burlington, Camden, Cape May, Cumberland, Gloucester and 2 more10 hr
May 30, 11:12 PM EDTFlash Flood WarningPHIGloucester, Salem3 hr
May 31, 12:34 AM EDTFlash Flood WarningPHIBurlington, Mercer3 hr
May 31, 4:00 AM EDTAreal Flood WarningPHIMorris, Sussex, Warren9 hr
May 31, 4:19 AM EDTAreal Flood WarningPHIHunterdon6 hr
May 31, 5:13 AM EDTAreal Flood WarningPHISomerset97 min
May 31, 8:46 AM EDTAreal Flood WarningPHISomerset7 hr
May 31, 2:12 PM EDTSpecial Marine WarningPHI63 min
May 31, 3:10 PM EDTSpecial Marine WarningPHI65 min
May 31, 3:14 PM EDTSevere Thunderstorm WarningPHICape May16 min
May 31, 4:51 PM EDTSpecial Marine WarningPHI84 min
May 31, 5:04 PM EDTSevere Thunderstorm WarningPHICumberland, Gloucester, Salem41 min
May 31, 6:20 PM EDTRiver Flood WarningPHIMorris12 hr
May 31, 1:04 AM EDTFlash Flood WarningPHIBerks, Bucks, Lehigh, Montgomery4 hr
May 31, 5:06 AM EDTAreal Flood WarningPHILehigh, Montgomery5 hr
May 31, 8:42 AM EDTAreal Flood WarningPHILehigh4 hr

Nearby

Flash Flood Warnings in Pennsylvania, 2025Flash Flood Warnings in New Jersey, 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.