Alert archive / New Jersey / Flash Flood Warnings in 2026

Flash Flood Warning 22, NWS Philadelphia/Mount Holly

July 6, 2026Hunterdon County, Mercer County, Somerset County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 6, 2026, 9:16 AM EDT for Hunterdon County, Mercer County, Somerset County, New Jersey. It was in force for 2 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
Jul 6, 2026, 9:16 AM EDT (13:16 UTC)
Expired
Jul 6, 2026, 11:31 AM EDT
In force
2 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Mercer County, NJ, Somerset County, NJ

The radar

The Philadelphia radar (KDIX), 60 km from the middle of the area, began a volume at 13:17 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 12:00Z, 1.3 hours before the alert went out and 177 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 2026-07-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 11 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 2026-07-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 34 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
11 J/kg
Mixed-layer CIN
-171 J/kg
Mixed-layer LCL
645 m above ground
0-6 km bulk shear
32 kt
0-1 km storm-relative helicity
34 m²/s²
0-3 km storm-relative helicity
170 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.1

Open this sounding in Storm Lab

The text

As transmitted.

022 
WGUS51 KPHI 061316
FFWPHI
NJC019-021-035-061715-
/O.NEW.KPHI.FF.W.0022.260706T1316Z-260706T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
916 AM EDT Mon Jul 6 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northwestern Mercer County in central New Jersey...
  Southwestern Somerset County in northern New Jersey...
  Southeastern Hunterdon County in northwestern New Jersey...

* Until 115 PM EDT.

* At 916 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 32 inches of rain 
  have fallen. 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...
  Pennington, Hopewell, Washington Crossing, Skillman and 
  Lambertville.

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 4042 7496 4046 7488 4046 7474 4039 7469
      4033 7473 4029 7487 4030 7487 4031 7488
      4031 7489 4032 7490 4035 7494

FLASH FLOOD...RADAR INDICATED

$$

Robertson
3 follow-up statements
482 
WGUS51 KPHI 061322 CCA
FFWPHI
NJC019-021-035-061715-
/O.COR.KPHI.FF.W.0022.260706T1316Z-260706T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning...CORRECTED
National Weather Service Mount Holly NJ
922 AM EDT Mon Jul 6 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northwestern Mercer County in central New Jersey...
  Southwestern Somerset County in northern New Jersey...
  Southeastern Hunterdon County in northwestern New Jersey...

* Until 115 PM EDT.

* At 916 AM EDT, Doppler radar indicated thunderstorms producing 
  heavy rain across the warned area. Between 2 and 3 inches of rain 
  have fallen. 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...
  Pennington, Hopewell, Washington Crossing, Skillman and 
  Lambertville.

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 4042 7496 4046 7488 4046 7474 4039 7469
      4033 7473 4029 7487 4030 7487 4031 7488
      4031 7489 4032 7490 4035 7494

FLASH FLOOD...RADAR INDICATED

$$

Robertson
473 
WGUS71 KPHI 061400
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1000 AM EDT Mon Jul 6 2026

NJC019-021-035-061715-
/O.CON.KPHI.FF.W.0022.000000T0000Z-260706T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Somerset NJ-
1000 AM EDT Mon Jul 6 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 115 PM EDT THIS 
AFTERNOON FOR NORTHWESTERN MERCER, SOUTHWESTERN SOMERSET AND 
SOUTHEASTERN HUNTERDON COUNTIES...

At 1000 AM EDT, Doppler radar indicated rainfall lessening in 
intensity across the warned area. However, between 2 and 3 inches of 
rain have fallen. 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...
  Pennington, Hopewell, Washington Crossing, Skillman and 
  Lambertville.

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 4042 7496 4046 7488 4046 7474 4039 7469
      4033 7473 4029 7487 4030 7487 4031 7488
      4031 7489 4032 7490 4035 7494

FLASH FLOOD...RADAR INDICATED

$$

Robertson
846 
WGUS71 KPHI 061531
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
1131 AM EDT Mon Jul 6 2026

NJC019-021-035-061541-
/O.CAN.KPHI.FF.W.0022.000000T0000Z-260706T1715Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Somerset NJ-
1131 AM EDT Mon Jul 6 2026

...FLASH FLOOD WARNING IS CANCELLED FOR NORTHWESTERN MERCER, 
SOUTHWESTERN SOMERSET AND SOUTHEASTERN HUNTERDON COUNTIES...

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 800 PM EDT Monday for portions 
of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4042 7496 4046 7488 4046 7474 4039 7469
      4033 7473 4029 7487 4030 7487 4031 7488
      4031 7489 4032 7490 4035 7494

$$

Robertson

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 5, 8:37 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset38 min
Jul 5, 9:14 PM EDTSevere Thunderstorm WarningPHIHunterdon, Morris, Somerset, Sussex46 min
Jul 5, 9:58 PM EDTSpecial Marine WarningPHI2 hr
Jul 5, 10:05 PM EDTSevere Thunderstorm WarningPHIGloucester, Salem40 min
Jul 5, 10:21 PM EDTSpecial Marine WarningPHI84 min
Jul 5, 10:37 PM EDTSevere Thunderstorm WarningPHICumberland, Gloucester, Salem38 min
Jul 5, 11:00 PM EDTFlash Flood Warning Considerable damage threatPHIBurlington, Camden, Gloucester, Salem4 hr
Jul 5, 11:30 PM EDTSevere Thunderstorm WarningPHICamden, Cumberland, Gloucester, Salem45 min
Jul 6, 12:01 AM EDTSevere Thunderstorm WarningPHIAtlantic, Burlington, Camden, Cumberland, Gloucester, Salem29 min
Jul 6, 9:27 AM EDTFlash Flood WarningPHICumberland, Gloucester, Salem3 hr
Jul 6, 10:15 AM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester4 hr
Jul 6, 10:27 AM EDTFlash Flood WarningPHIBurlington, Camden, Gloucester, Salem4 hr
Jul 6, 10:38 AM EDTFlash Flood WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean4 hr
Jul 6, 11:01 AM EDTSpecial Marine WarningPHI78 min
Jul 6, 11:02 AM EDTFlash Flood WarningPHIMiddlesex, Monmouth4 hr
Jul 6, 11:13 AM EDTFlash Flood Warning Considerable damage threatPHIBurlington3 hr
Jul 6, 11:44 AM EDTFlash Flood Warning Considerable damage threatPHIMonmouth, Ocean4 hr
Jul 6, 1:46 PM EDTSpecial Marine WarningPHI59 min
Jul 6, 2:15 PM EDTAreal Flood WarningPHIBurlington, Camden, Gloucester4 hr
Jul 6, 2:40 PM EDTAreal Flood WarningPHIBurlington4 hr
Jul 6, 3:07 PM EDTAreal Flood WarningPHIMonmouth, Ocean4 hr
Jul 6, 3:39 PM EDTSpecial Marine WarningPHI48 min
Jul 6, 3:50 PM EDTSpecial Marine WarningPHI55 min
Jul 6, 4:36 PM EDTSpecial Marine WarningPHI54 min
Jul 6, 5:23 PM EDTSpecial Marine WarningPHI82 min

Nearby

Flash 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.