Alert archive / Pennsylvania / Flash Flood Warnings in 2025

Flash Flood Warning 31, NWS Philadelphia/Mount Holly

July 1, 2025Berks County, Chester County, Montgomery County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 1, 2025, 4:55 PM EDT for Berks County, Chester County, Montgomery County, Pennsylvania. It was in force for 4 hr. 10 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 1, 2025, 4:55 PM EDT (20:55 UTC)
Expired
Jul 1, 2025, 9:00 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Berks County, PA, Chester County, PA, Montgomery County, PA

The radar

The Philadelphia radar (KDIX), 123 km from the middle of the area, began a volume at 20:56 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
Jul 1, 5:02 PM EDTFLASH FLOODWernersville, PAFlooding occurring in Wernersville.
Jul 1, 5:04 PM EDTFLASH FLOOD1 N Lorane, PAVehicle stuck in flood water under a railroad underpass on Gibraltar Road.
Jul 1, 5:05 PM EDTFLASH FLOODAlleghenyville, PAVehicle stuck in flood water at the intersection of Maple Grove Road & Kramer Road.
Jul 1, 5:09 PM EDTFLASH FLOOD2 Wsw Robeson Twp, PAVehicle stuck in 4 feet of water on Westley Road.
Jul 1, 5:21 PM EDTFLASH FLOODMuhlenberg Twp, PAVehicle stuck in water on Route 61.
Jul 1, 6:00 PM EDTFLASH FLOOD3 Sw Earl Twp, PAThe Manatawny Creek at Spangville (SPGP1) rapidly rose into flood stage.
Jul 1, 6:11 PM EDTFLASH FLOODMuhlenberg Twp, PAThe road is washed out at the intersection of Frush Valley Road and Mt Laurel Road.
Jul 1, 6:31 PM EDTFLASH FLOODMuhlenburg, PAWater Street flooded in Muhlenburg.
Jul 1, 6:45 PM EDTRAIN 2.7Douglassville, PARainfall from 4:30 PM to 6:00 PM.
Jul 1, 7:47 PM EDTFLASH FLOODRobeson Twp, PAPart of Moyer Road collapsed due to flash flooding.

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, 8.9 hours before the alert went out and 203 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, Washington/Dulle, VA at 12:00Z on 2025-07-01Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 822 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, Washington/Dulle, VA at 12:00Z on 2025-07-01The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity -2 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
822 J/kg
Mixed-layer CIN
-69 J/kg
Mixed-layer LCL
994 m above ground
0-6 km bulk shear
19 kt
0-1 km storm-relative helicity
-2 m²/s²
0-3 km storm-relative helicity
32 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

694 
WGUS51 KPHI 012055
FFWPHI
PAC011-029-091-020100-
/O.NEW.KPHI.FF.W.0031.250701T2055Z-250702T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
455 PM EDT Tue Jul 1 2025

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Southeastern Berks County in eastern Pennsylvania...
  North Central Chester County in southeastern Pennsylvania...
  West Central Montgomery County in southeastern Pennsylvania...

* Until 900 PM EDT.

* At 455 PM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 1 and 2 inches of rain 
  have fallen. The expected rainfall rate is 0.5 to 1.5 inches in 1 
  hour. Additional rainfall amounts of 0.5 to 1 inch 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...
  Reading, Pottstown, Phoenixville, Wyomissing, Birdsboro, 
  Royersford, Sinking Spring, Laureldale, Wernersville, Elverson, 
  New Morgan and Cedarville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 4036 7576 4031 7557 4026 7548 4015 7551
      4014 7587 4014 7588 4032 7615 4040 7602
      4043 7593

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

$$

Hoeflich
2 follow-up statements
535 
WGUS71 KPHI 012121
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
521 PM EDT Tue Jul 1 2025

PAC011-029-091-020100-
/O.CON.KPHI.FF.W.0031.000000T0000Z-250702T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks PA-Chester PA-Montgomery PA-
521 PM EDT Tue Jul 1 2025

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 9 PM EDT THIS EVENING 
FOR SOUTHEASTERN BERKS, NORTH CENTRAL CHESTER AND WEST CENTRAL 
MONTGOMERY COUNTIES...

At 521 PM EDT, local law enforcement reported thunderstorms 
producing heavy rain. At Westley Road in Mohnton, a water rescue was 
reported. Between 2 and 3 inches of rain have fallen. The expected 
rainfall rate is 0.75 to 1.5 inches in 1 hour. Additional rainfall 
amounts of 0.5 to 1 inch are possible in the warned area. Flash 
flooding is already occurring.

HAZARD...Flash flooding caused by thunderstorms.

SOURCE...Law enforcement 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...
  Reading, Pottstown, Phoenixville, Wyomissing, Birdsboro, 
  Royersford, Sinking Spring, Laureldale, Wernersville, Elverson, 
  New Morgan and Cedarville.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Turn around...don't drown when encountering flooded roads. Most 
flood deaths occur in vehicles.

&&

LAT...LON 4036 7576 4031 7557 4026 7548 4015 7551
      4014 7587 4014 7588 4032 7615 4040 7602
      4043 7593

FLASH FLOOD...OBSERVED
EXPECTED RAINFALL RATE...0.75-1.5 INCHES IN 1 HOUR

$$

Hoeflich
720 
WGUS71 KPHI 020056
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
856 PM EDT Tue Jul 1 2025

PAC011-029-091-020106-
/O.EXP.KPHI.FF.W.0031.000000T0000Z-250702T0100Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Berks PA-Chester PA-Montgomery PA-
856 PM EDT Tue Jul 1 2025

...FLASH FLOOD WARNING WILL EXPIRE AT 9 PM EDT THIS EVENING FOR 
SOUTHEASTERN BERKS, NORTH CENTRAL CHESTER AND WEST CENTRAL 
MONTGOMERY COUNTIES...

Flash Flooding is no longer expected to pose a threat. Please 
continue to heed remaining road closures. A more targeted Flood 
Warning was just issued for the Reading area. Please refer to that 
bulletin for the updated information.


&&

LAT...LON 4036 7576 4031 7557 4026 7548 4015 7551
      4014 7587 4014 7588 4032 7615 4040 7602
      4043 7593

$$

Hoeflich

The office that day

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

IssuedProductOfficeCountiesLasted
Jun 30, 11:20 PM EDTFlash Flood WarningPHIBerks4 hr
Jun 30, 11:47 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Delaware, Montgomery43 min
Jul 1, 12:38 AM EDTSevere Thunderstorm WarningPHIChester, Delaware36 min
Jul 1, 2:30 AM EDTFlood WatchPHIBerks, Bucks, Chester, Delaware, Montgomery, Philadelphia19 hr
Jul 1, 6:15 AM EDTRiver Flood WarningPHIChester3 hr
Jul 1, 6:21 AM EDTAreal Flood WarningPHIDelaware2 hr
Jul 1, 2:32 PM EDTSevere Thunderstorm WarningPHIChester43 min
Jul 1, 2:58 PM EDTSevere Thunderstorm WarningPHIBucks, Montgomery, Philadelphia47 min
Jul 1, 3:00 PM EDTFlash Flood WarningPHIChester4 hr
Jul 1, 3:06 PM EDTRiver Flood WarningPHIChester, Delaware8 hr
Jul 1, 3:31 PM EDTFlash Flood WarningPHIBucks, Montgomery, Philadelphia4 hr
Jul 1, 3:34 PM EDTSevere Thunderstorm WarningPHIBerks56 min
Jul 1, 3:39 PM EDTSevere Thunderstorm WarningPHIBucks, Philadelphia66 min
Jul 1, 4:27 PM EDTSevere Thunderstorm WarningPHIBerks, Chester, Lehigh, Montgomery63 min
Jul 1, 4:44 PM EDTFlash Flood WarningPHIChester4 hr
Jul 1, 4:47 PM EDTTornado WarningPHIBerks, Montgomery28 min
Jul 1, 5:07 PM EDTSevere Thunderstorm WarningPHIBerks, Bucks, Lehigh, Montgomery, Northampton38 min
Jul 1, 5:14 PM EDTFlash Flood WarningPHIBerks, Bucks, Lehigh, Montgomery4 hr

Nearby

Flash 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.