Alert archive / New Jersey / Flash Flood Warnings in 2026

Flash Flood Warning 106, NWS Philadelphia/Mount Holly

August 6, 2026Morris County, New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Aug 6, 2026, 12:31 AM EDT for Morris County, New Jersey. It was in force for 4 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 6, 2026, 12:31 AM EDT (04:31 UTC)
Expired
Aug 6, 2026, 4:30 AM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

County Morris County, NJ

The radar

The Philadelphia radar (KDIX), 115 km from the middle of the area, began a volume at 04:32 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, 4.5 hours before the alert went out and 126 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 2026-08-06Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 94 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 2026-08-06The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 83 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
94 J/kg
Mixed-layer CIN
-35 J/kg
Mixed-layer LCL
462 m above ground
0-6 km bulk shear
22 kt
0-1 km storm-relative helicity
83 m²/s²
0-3 km storm-relative helicity
123 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted.

561 
WGUS51 KPHI 060431
FFWPHI
NJC027-060830-
/O.NEW.KPHI.FF.W.0106.260806T0431Z-260806T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
1231 AM EDT Thu Aug 6 2026

The National Weather Service in Mount Holly has issued a

* Flash Flood Warning for...
  Northeastern Morris County in northern New Jersey...

* Until 430 AM EDT.

* At 1231 AM EDT, Doppler radar 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.

  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...
  Lincoln Park, Kinnelon, Boonton, Butler, Riverdale, Pequannock 
  Township, Green Pond and Lake Telemark.

This includes Interstate 287 in New Jersey between mile markers 46 
and 53.

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.

Be aware of your surroundings and do not drive on flooded roads.

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 4091 7433 4089 7434 4087 7434 4097 7454
      4105 7444 4104 7443 4102 7443 4103 7442
      4101 7439 4101 7436 4100 7435 4101 7434
      4100 7431 4100 7430 4099 7429 4098 7430
      4097 7428 4095 7428 4091 7430

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

$$

MPS
2 follow-up statements
616 
WGUS71 KPHI 060558
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
158 AM EDT Thu Aug 6 2026

NJC027-060830-
/O.CON.KPHI.FF.W.0106.000000T0000Z-260806T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
158 AM EDT Thu Aug 6 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 AM EDT EARLY THIS 
MORNING FOR NORTHEASTERN MORRIS COUNTY...

At 158 AM EDT, Doppler radar indicated thunderstorms produced heavy 
rain across the warned area, and additonal rainfall is likely. 
Between 1.5 and 2.5 inches of rain have fallen. Additional rainfall 
amounts of up to 0.5 inches 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...
  Lincoln Park, Kinnelon, Boonton, Butler, Riverdale, Pequannock 
  Township, Green Pond and Lake Telemark.

This includes Interstate 287 in New Jersey between mile markers 46 
and 53.

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.

Be aware of your surroundings and do not drive on flooded roads.

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 4091 7433 4089 7434 4087 7434 4097 7454
      4105 7444 4104 7443 4102 7443 4103 7442
      4101 7439 4101 7436 4100 7435 4101 7434
      4100 7431 4100 7430 4099 7429 4098 7430
      4097 7428 4095 7428 4091 7430

FLASH FLOOD...RADAR INDICATED

$$

MPS
977 
WGUS71 KPHI 060706
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
306 AM EDT Thu Aug 6 2026

NJC027-060830-
/O.CON.KPHI.FF.W.0106.000000T0000Z-260806T0830Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Morris NJ-
306 AM EDT Thu Aug 6 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 430 AM EDT EARLY THIS 
MORNING FOR NORTHEASTERN MORRIS COUNTY...

At 306 AM EDT, Doppler radar and automated rain gauges indicated 
thunderstorms produced 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...
  Lincoln Park, Kinnelon, Boonton, Butler, Riverdale, Pequannock 
  Township, Green Pond and Lake Telemark.

This includes Interstate 287 in New Jersey between mile markers 46 
and 53.

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.

Be aware of your surroundings and do not drive on flooded roads.

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 4091 7433 4089 7434 4087 7434 4097 7454
      4105 7444 4104 7443 4102 7443 4103 7442
      4101 7439 4101 7436 4100 7435 4101 7434
      4100 7431 4100 7430 4099 7429 4098 7430
      4097 7428 4095 7428 4091 7430

FLASH FLOOD...RADAR AND GAUGE INDICATED

$$

Staarmann

The office that day

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

IssuedProductOfficeCountiesLasted
Aug 5, 11:40 PM EDTFlash Flood WarningPHIHunterdon, Morris, Somerset4 hr

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.