Alert archive / Pennsylvania / Flash Flood Warnings in 2026

Flash Flood Warning 87, NWS Philadelphia/Mount Holly

August 3, 2026Hunterdon County, Warren County, New Jersey; Bucks County, Monroe County, Northampton County, Pennsylvania

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 3, 2026, 12:05 AM EDT for Hunterdon County, Warren County, New Jersey; Bucks County, Monroe County, Northampton County, Pennsylvania. It was in force for 3 hr. No storm report in the archive falls inside the area while it was in force.

The area

The outline as issued.

The facts

Issued
Aug 3, 2026, 12:05 AM EDT (04:05 UTC)
Expired
Aug 3, 2026, 3:30 AM EDT
In force
3 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Warren County, NJ, Bucks County, PA, Monroe County, PA, Northampton County, PA

The radar

The Philadelphia radar (KDIX), 128 km from the middle of the area, began a volume at 04:07 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.

The nearest sounding before it

Brookhaven, NY (KOKX), launched 00:00Z, 4.1 hours before the alert went out and 184 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 2026-08-03Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 151 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 2026-08-03The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 163 square meters per square second.193958Sfc1 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
151 J/kg
Mixed-layer CIN
-2 J/kg
Mixed-layer LCL
507 m above ground
0-6 km bulk shear
38 kt
0-1 km storm-relative helicity
163 m²/s²
0-3 km storm-relative helicity
198 m²/s²
Significant tornado parameter
0.1
Supercell composite
1.7

Open this sounding in Storm Lab

The text

As transmitted.

090 
WGUS51 KPHI 030405
FFWPHI
NJC019-041-PAC017-089-095-030730-
/O.NEW.KPHI.FF.W.0087.260803T0405Z-260803T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1205 AM EDT Mon Aug 3 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  West Central Hunterdon County in northwestern New Jersey...
  Warren County in northwestern New Jersey...
  Eastern Northampton County in eastern Pennsylvania...
  Southeastern Monroe County in northeastern Pennsylvania...
  North Central Bucks County in southeastern Pennsylvania...

* Until 330 AM EDT.

* At 1205 AM 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 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...
  Easton, East Stroudsburg, Washington, Blairstown, Bangor, Pen 
  Argyl, Wind Gap, Belvidere, Harmony, Oxford, Alpha and Hope.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 0 and 8.
	Interstate 80 in New Jersey between mile markers 0 and 13.
	Interstate 80 in Pennsylvania between mile markers 311 and 314.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4113 7507 4109 7504 4108 7503 4108 7502
      4108 7501 4109 7501 4109 7500 4109 7499
      4109 7498 4108 7495 4102 7489 4059 7507
      4052 7527 4081 7516 4086 7531

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

$$

Cooper
2 follow-up statements
838 
WGUS71 KPHI 030512
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
112 AM EDT Mon Aug 3 2026

NJC019-041-PAC017-089-095-030730-
/O.CON.KPHI.FF.W.0087.000000T0000Z-260803T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Bucks PA-Monroe PA-Northampton PA-
112 AM EDT Mon Aug 3 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 330 AM EDT EARLY THIS 
MORNING FOR WEST CENTRAL HUNTERDON, WARREN, EASTERN NORTHAMPTON, 
SOUTHEASTERN MONROE AND NORTH CENTRAL BUCKS COUNTIES...

At 112 AM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms producing heavy rain across the warned area. Between 
1.5 and 2.5 inches of rain have fallen. Flooding impacts will 
continue, but no additional rainfall is expected. 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...
  Easton, East Stroudsburg, Washington, Blairstown, Bangor, Pen 
  Argyl, Wind Gap, Belvidere, Harmony, Oxford, Alpha and Hope.

This includes the following highways...
	Interstate 78 in New Jersey between mile markers 0 and 9.
	Interstate 80 in New Jersey between mile markers 0 and 13.
	Interstate 80 in Pennsylvania between mile markers 311 and 314.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4113 7507 4109 7504 4108 7503 4108 7502
      4108 7501 4109 7501 4109 7500 4109 7499
      4109 7498 4108 7495 4102 7489 4059 7507
      4052 7527 4081 7516 4086 7531

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Cooper
370 
WGUS71 KPHI 030721 RRA
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
321 AM EDT Mon Aug 3 2026

NJC019-041-PAC017-089-095-030731-
/O.EXP.KPHI.FF.W.0087.000000T0000Z-260803T0730Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Warren NJ-Bucks PA-Monroe PA-Northampton PA-
321 AM EDT Mon Aug 3 2026

...FLASH FLOOD WARNING WILL EXPIRE AT 330 AM EDT EARLY THIS MORNING 
FOR WEST CENTRAL HUNTERDON, WARREN, EASTERN NORTHAMPTON, 
SOUTHEASTERN MONROE AND NORTH CENTRAL BUCKS 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.

A Flood Watch remains in effect until 1100 PM EDT Monday for 
portions of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4113 7507 4109 7504 4108 7503 4108 7502
      4108 7501 4109 7501 4109 7500 4109 7499
      4109 7498 4108 7495 4102 7489 4059 7507
      4052 7527 4081 7516 4086 7531

$$

Cooper

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 2, 11:20 PM EDTFlash Flood WarningPHIWarren4 hr
Aug 3, 12:36 AM EDTSpecial Marine WarningPHI84 min
Aug 3, 2:50 AM EDTFlash Flood WarningPHIHunterdon, Mercer, Morris, Somerset4 hr
Aug 3, 3:05 AM EDTSevere Thunderstorm WarningPHIHunterdon, Mercer, Somerset40 min
Aug 3, 4:41 AM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester, Mercer, Middlesex, Somerset2 hr
Aug 3, 5:59 AM EDTFlash Flood WarningPHIMiddlesex, Somerset4 hr
Aug 3, 7:02 AM EDTAreal Flood WarningPHIBurlington, Camden, Gloucester, Mercer, Middlesex, Somerset3 hr
Aug 3, 8:21 AM EDTSpecial Marine WarningPHI69 min
Aug 3, 9:08 AM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester, Mercer, Salem3 hr
Aug 3, 10:12 AM EDTFlash Flood WarningPHIAtlantic, Cumberland, Salem86 min
Aug 3, 10:36 AM EDTFlash Flood WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean, Somerset6 hr
Aug 3, 10:44 AM EDTFlash Flood Warning Considerable damage threatPHIBurlington, Camden, Gloucester6 hr
Aug 3, 12:01 PM EDTAreal Flood WarningPHIMercer74 min
Aug 3, 1:20 PM EDTAreal Flood WarningPHIBurlington, Camden, Mercer4 hr
Aug 3, 1:51 PM EDTSpecial Marine WarningPHI24 min
Aug 3, 2:53 PM EDTSpecial Marine WarningPHI97 min
Aug 3, 2:57 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean27 min
Aug 3, 5:15 PM EDTSpecial Marine WarningPHI90 min
Aug 3, 3:01 AM EDTFlash Flood WarningPHIBucks, Chester, Delaware, Montgomery3 hr
Aug 3, 6:26 AM EDTAreal Flood WarningPHIBucks, Montgomery94 min

Nearby

Flash Flood Warnings in Pennsylvania, 2026Flash Flood Warnings in New Jersey, 2026Every flash flood warning in 2026

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.