Flash Flood Warning 151, NWS Philadelphia/Mount Holly

Issued

Sep 1, 2026, 9:19 PM EDT (01:19 UTC)

Expired

Sep 1, 2026, 11:15 PM EDT

In force

116 min

Issued by

NWS Philadelphia/Mount Holly

Area

Storm-based polygon

Flood severity

None

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Bucks County, PA

The Philadelphia radar (KDIX), 39 km from the middle of the area, began a volume at 01:19 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.

698 
WGUS51 KPHI 020119
FFWPHI
NJC019-021-023-PAC017-020515-
/O.NEW.KPHI.FF.W.0151.260902T0119Z-260902T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
919 PM EDT Tue Sep 1 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Mercer County in central New Jersey...
  Southwestern Middlesex County in northern New Jersey...
  Southeastern Hunterdon County in northwestern New Jersey...
  Southeastern Bucks County in southeastern Pennsylvania...

* Until 115 AM EDT.

* At 919 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 1 to 2 inches in 1 hour.
  Flash flooding is ongoing or expected to begin shortly.

  HAZARD...Flash flooding caused by thunderstorms.

  SOURCE...Radar indicated.

  IMPACT...Flash flooding of small creeks and streams, urban areas,
           highways, streets and underpasses as well as other poor
           drainage and low-lying areas.

* Some locations that will experience flash flooding include...
  Trenton, Ewing, Princeton, Bristol, Hightstown, Pennington,
  Yardley, Newtown, Hopewell and Tullytown.

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.

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 4043 7479 4040 7474 4038 7472 4038 7469
      4027 7447 4025 7447 4025 7449 4024 7448
      4022 7454 4019 7456 4018 7461 4014 7459
      4014 7462 4018 7470 4015 7472 4012 7478
      4013 7482 4010 7484 4008 7487 4025 7507

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

$$

MPS

044 
WGUS71 KPHI 020315
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1115 PM EDT Tue Sep 1 2026

NJC019-021-023-PAC017-020325-
/O.CAN.KPHI.FF.W.0151.000000T0000Z-260902T0515Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Middlesex NJ-Bucks PA-
1115 PM EDT Tue Sep 1 2026

...FLASH FLOOD WARNING IS CANCELLED FOR MERCER, SOUTHWESTERN
MIDDLESEX, SOUTHEASTERN HUNTERDON AND SOUTHEASTERN BUCKS COUNTIES...

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

&&

LAT...LON 4043 7479 4040 7474 4038 7472 4038 7469
      4027 7447 4025 7447 4025 7449 4024 7448
      4022 7454 4019 7456 4018 7461 4014 7459
      4014 7462 4018 7470 4015 7472 4012 7478
      4013 7482 4010 7484 4008 7487 4025 7507

$$

MPS

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

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.