Flash Flood Warning 115, NWS Philadelphia/Mount Holly

Issued

Aug 7, 2026, 5:42 PM EDT (21:42 UTC)

Expired

Aug 7, 2026, 8:45 PM EDT

In force

3 hr

Issued by

NWS Philadelphia/Mount Holly

Area

Storm-based polygon

Flood severity

None

Counties Mercer County, NJ, Middlesex County, NJ, Morris County, NJ, Somerset County, NJ

The Philadelphia radar (KDIX), 85 km from the middle of the area, began a volume at 21:41 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.

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

768 
WGUS51 KPHI 072142
FFWPHI
NJC021-023-027-035-080045-
/O.NEW.KPHI.FF.W.0115.260807T2142Z-260808T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
542 PM EDT Fri Aug 7 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northeastern Mercer County in central New Jersey...
  Middlesex County in northern New Jersey...
  Southeastern Morris County in northern New Jersey...
  Central Somerset County in northern New Jersey...

* Until 845 PM EDT.

* At 542 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...
  New Brunswick, Morristown, Somerville, Somerset, Edison, East 
  Brunswick, South Brunswick, North Brunswick, Madison, Middlesex, 
  Princeton and Florham Park.

This includes the following highways...
	New Jersey Turnpike between exits 8A and 11.
	Interstate 287 in New Jersey between mile markers 0 and 16...and
	between mile markers 27 and 47.
	Interstate 78 in New Jersey between mile markers 34 and 42.
	Interstate 80 in New Jersey between mile markers 40 and 48.
	Garden State Parkway between mile markers 130 and 134.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4092 7447 4092 7427 4091 7427 4090 7428
      4091 7433 4086 7432 4076 7438 4075 7436
      4067 7446 4066 7445 4066 7440 4060 7446
      4061 7431 4059 7429 4060 7427 4023 7452
      4034 7468 4065 7460

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

$$

Cooper

972 
WGUS71 KPHI 072225
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
625 PM EDT Fri Aug 7 2026

NJC021-023-027-035-080045-
/O.CON.KPHI.FF.W.0115.000000T0000Z-260808T0045Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Mercer NJ-Middlesex NJ-Morris NJ-Somerset NJ-
625 PM EDT Fri Aug 7 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 845 PM EDT THIS 
EVENING FOR NORTHEASTERN MERCER, MIDDLESEX, SOUTHEASTERN MORRIS AND 
CENTRAL SOMERSET COUNTIES...

At 625 PM EDT, the public reported thunderstorms producing heavy 
rain across the warned area with roads flooded in New Brunswick. 
Between 1 and 2 inches of rain have fallen. 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...Public 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...
  New Brunswick, Morristown, Somerville, Somerset, Edison, East 
  Brunswick, South Brunswick, North Brunswick, Madison, Middlesex, 
  Princeton and Florham Park.

This includes the following highways...
	New Jersey Turnpike between exits 8A and 11.
	Interstate 287 in New Jersey between mile markers 0 and 17...and
	between mile markers 27 and 47.
	Interstate 78 in New Jersey between mile markers 34 and 42.
	Interstate 80 in New Jersey between mile markers 40 and 48.
	Garden State Parkway between mile markers 130 and 134.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4092 7447 4092 7427 4091 7427 4090 7428
      4091 7433 4086 7432 4076 7438 4075 7436
      4067 7446 4066 7445 4066 7440 4060 7446
      4061 7431 4059 7429 4060 7427 4023 7452
      4034 7468 4065 7460

FLASH FLOOD...OBSERVED

$$

Cooper

Flash Flood Warnings in New Jersey, 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.