Alert archive / Pennsylvania / Flash Flood Warnings in 2025

Flash Flood Warning 91, NWS Philadelphia/Mount Holly

August 13, 2025Bucks County, Montgomery County, Philadelphia County, Pennsylvania; Burlington County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 13, 2025, 6:54 PM EDT for Bucks County, Montgomery County, Philadelphia County, Pennsylvania; Burlington County, New Jersey. It was in force for 2 hr. 4 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 13, 2025, 6:54 PM EDT (22:54 UTC)
Expired
Aug 13, 2025, 9:00 PM EDT
In force
2 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Burlington County, NJ, Bucks County, PA, Montgomery County, PA, Philadelphia County, PA

The radar

The Philadelphia radar (KDIX), 47 km from the middle of the area, began a volume at 22:55 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
Aug 13, 7:20 PM EDTFLASH FLOOD1 E Beverly, NJThe Warren Street underpass at the River Line bridge in Edgewater Park is closed due to flooding. Time estimated.
Aug 13, 7:22 PM EDTFLASH FLOOD1 Ssw Summerdale, PAThe Frankford Creek at Philadelphia reached flood stage.
Aug 13, 7:22 PM EDTFLASH FLOOD1 Ssw Summerdale, PACorrects previous flash flood report from 1 SSW Summerdale. The Frankford Creek at Philadelphia reached flood stage.
Aug 13, 7:44 PM EDTFLASH FLOODBurlington Twp, NJPinewald Lane flooded.

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 12:00Z, 10.9 hours before the alert went out and 195 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 12:00Z on 2025-08-13Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 1273 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 12:00Z on 2025-08-13The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 44 square meters per square second.1939Sfc1 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
1273 J/kg
Mixed-layer CIN
-45 J/kg
Mixed-layer LCL
892 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
44 m²/s²
0-3 km storm-relative helicity
60 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.9

Open this sounding in Storm Lab

The text

As transmitted.

947 
WGUS51 KPHI 132254
FFWPHI
NJC005-PAC017-091-101-140300-
/O.NEW.KPHI.FF.W.0091.250813T2254Z-250814T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
654 PM EDT Wed Aug 13 2025

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northwestern Burlington County in southern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...
  Southeastern Montgomery County in southeastern Pennsylvania...
  Philadelphia County in southeastern Pennsylvania...

* Until 1100 PM EDT.

* At 654 PM EDT, Doppler radar and automated rain gauges 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 
  to 2 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 and automated gauges.

  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, Bensalem, Willingboro, Florence, Burlington, 
  Bristol, Mount Holly, Riverside, Palmyra, Jenkintown, Narberth and 
  Bordentown.

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 4004 7534 4011 7521 4019 7494 4017 7473
      4015 7472 4016 7471 4017 7471 4017 7469
      4009 7464 3998 7467 4000 7503 3998 7509
      3999 7529

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...1-2 INCHES IN 1 HOUR

$$

Staarmann
2 follow-up statements
604 
WGUS71 KPHI 132331
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
731 PM EDT Wed Aug 13 2025

NJC005-PAC017-091-101-140300-
/O.CON.KPHI.FF.W.0091.000000T0000Z-250814T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Bucks PA-Montgomery PA-Philadelphia PA-
731 PM EDT Wed Aug 13 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 11 PM EDT THIS 
EVENING FOR NORTHWESTERN BURLINGTON, SOUTHEASTERN BUCKS, 
SOUTHEASTERN MONTGOMERY AND PHILADELPHIA COUNTIES...

At 731 PM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 
0.5 and 1.5 inches of rain have fallen. The expected rainfall rate 
is 0.5 to 1 inch in 1 hour. Additional rainfall amounts up to 0.5 
inches are possible in the warned area. Flash flooding is already 
occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Radar and automated gauges.

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...
  Portions of Philadelphia north of Center City, Bensalem, 
  Willingboro, Florence, Burlington, Bristol, Mount Holly, 
  Riverside, Palmyra, Jenkintown, Narberth and Bordentown.

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.

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 4004 7534 4011 7521 4019 7494 4017 7473
      4015 7472 4016 7471 4017 7471 4017 7469
      4009 7464 3998 7467 4000 7503 3998 7509
      3999 7529

FLASH FLOOD...RADAR AND GAUGE INDICATED
EXPECTED RAINFALL RATE...0.5-1 INCH IN 1 HOUR

$$

Staarmann
770 
WGUS71 KPHI 140100
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
900 PM EDT Wed Aug 13 2025

NJC005-PAC017-091-101-140110-
/O.CAN.KPHI.FF.W.0091.000000T0000Z-250814T0300Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Burlington NJ-Bucks PA-Montgomery PA-Philadelphia PA-
900 PM EDT Wed Aug 13 2025

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN BURLINGTON, 
SOUTHEASTERN BUCKS, SOUTHEASTERN MONTGOMERY AND PHILADELPHIA 
COUNTIES...

The heavy rain has ended and flood waters are receding. Flooding is 
no longer expected to pose a threat. Please continue to heed 
remaining road closures.

&&

LAT...LON 4004 7534 4011 7521 4019 7494 4017 7473
      4015 7472 4016 7471 4017 7471 4017 7469
      4009 7464 3998 7467 4000 7503 3998 7509
      3999 7529

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 13, 12:07 PM EDTFlood WatchPHIBucks, Chester, Delaware, Montgomery, Philadelphia9 hr
Aug 13, 4:49 PM EDTSevere Thunderstorm WarningPHIBucks, Lehigh, Northampton41 min
Aug 13, 6:26 PM EDTSevere Thunderstorm WarningPHIChester, Delaware49 min
Aug 13, 6:59 PM EDTFlash Flood WarningPHIChester2 hr
Aug 13, 4:47 PM EDTSpecial Marine WarningPHI88 min
Aug 13, 5:26 PM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Middlesex, Morris, Somerset36 min
Aug 13, 6:46 PM EDTSpecial Marine WarningPHI89 min
Aug 13, 6:46 PM EDTSevere Thunderstorm WarningPHIMonmouth44 min

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.