Alert archive / New Jersey / Flash Flood Warnings in 2026

Flash Flood Warning 49, NWS Philadelphia/Mount Holly

July 18, 20264 counties in New Jersey

NWS Philadelphia/Mount Holly issued this flash flood warning at Jul 18, 2026, 2:36 PM EDT for 4 counties in New Jersey. It was in force for 4 hr. 5 reports came from inside the area while it was in force.

The area

The outline as issued, with what was reported inside it.

The facts

Issued
Jul 18, 2026, 2:36 PM EDT (18:36 UTC)
Expired
Jul 18, 2026, 6:45 PM EDT
In force
4 hr
Issued by
NWS Philadelphia/Mount Holly
Area
Storm-based polygon
Flood severity
None

Counties Hunterdon County, NJ, Mercer County, NJ, Middlesex County, NJ, Monmouth County, NJ

The radar

The Philadelphia radar (KDIX), 49 km from the middle of the area, began a volume at 18:37 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.

What was reported inside it

TimeReportWhereRemark
Jul 18, 3:22 PM EDTFLOODMonmouth Hills, NJNJDOT reported Flooding on NJ 36 Both Directions At Linden Av (Highlands), All lanes closed eastbound; All lanes closed westbound.
Jul 18, 3:22 PM EDTFLASH FLOODMonmouth Hills, NJCorrects previous flood report from Monmouth Hills. NJDOT reported Flooding on NJ 36 Both Directions At Linden Av (Highlands), All lanes closed eastbound; All lanes closed westbound.
Jul 18, 3:31 PM EDTFLASH FLOODPort Monmouth, NJNJDOT reported flooding on NJ 36 Northbound At Wilson Av (Middletown Twp), All lanes closed.
Jul 18, 3:54 PM EDTFLASH FLOOD2 Sse Middletown Twp, NJNJDOT reported flooding on NJ 35 Northbound South of Oak Hill Rd/Cooper Rd (Middletown Twp), All lanes closed.
Jul 18, 4:52 PM EDTFLASH FLOODAtlantic Highlands, NJRoad flooded in Highlands. Time from report.

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

The nearest sounding before it

Brookhaven, NY (KOKX), launched 12:00Z, 6.6 hours before the alert went out and 145 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 2026-07-18Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 5 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 2026-07-18The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 131 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
5 J/kg
Mixed-layer CIN
-238 J/kg
Mixed-layer LCL
1076 m above ground
0-6 km bulk shear
45 kt
0-1 km storm-relative helicity
131 m²/s²
0-3 km storm-relative helicity
157 m²/s²
Significant tornado parameter
0.0
Supercell composite
1.0

Open this sounding in Storm Lab

The text

As transmitted.

351 
WGUS51 KPHI 181836
FFWPHI
NJC019-021-023-025-182245-
/O.NEW.KPHI.FF.W.0049.260718T1836Z-260718T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/

BULLETIN - EAS ACTIVATION REQUESTED
Flash Flood Warning
National Weather Service Mount Holly NJ
236 PM EDT Sat Jul 18 2026

The National Weather Service in Mount Holly has issued a

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

* Until 645 PM EDT.

* At 236 PM 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 0.5 to 1.5 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...
  Trenton, Sandy Hook, Middletown, Old Bridge, East Brunswick, 
  Ewing, Holmdel, Princeton, Red Bank, Keansburg, Matawan and 
  Jamesburg.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 67 and 76.
	New Jersey Turnpike near exit 9.
	Garden State Parkway between mile markers 112 and 121.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4036 7479 4035 7476 4041 7428 4045 7422
      4044 7421 4046 7414 4040 7398 4048 7401
      4044 7398 4038 7388 4024 7483 4030 7487
      4034 7494 4039 7496 4041 7479

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

$$

Kruzdlo
2 follow-up statements
891 
WGUS71 KPHI 181906
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
306 PM EDT Sat Jul 18 2026

NJC019-021-023-025-182245-
/O.CON.KPHI.FF.W.0049.000000T0000Z-260718T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Middlesex NJ-Monmouth NJ-
306 PM EDT Sat Jul 18 2026

...FLASH FLOOD WARNING REMAINS IN EFFECT UNTIL 645 PM EDT THIS 
EVENING FOR NORTHEASTERN MERCER, NORTHWESTERN MONMOUTH, SOUTHWESTERN 
MIDDLESEX AND SOUTHEASTERN HUNTERDON COUNTIES...

At 306 PM EDT, Doppler radar indicated thunderstorms producing heavy 
rain across the warned area. Between 0.5 and 2 inches of rain have 
fallen. The expected rainfall rate is 1 to 3 inches in 1 hour. 
Additional rainfall amounts of 0.5 to 2 inches are possible in the 
warned area. Flash flooding is ongoing or expected to begin shortly.

HAZARD...Life threatening flash flooding caused by thunderstorms.

SOURCE...Radar.

IMPACT...Life threatening flash flooding of creeks and streams,
         urban areas, highways, streets, and underpasses.

Some locations that may experience flash flooding include...
  Trenton, Sandy Hook, Middletown, Old Bridge, East Brunswick, 
  Ewing, Holmdel, Princeton, Red Bank, Keansburg, Matawan and 
  Jamesburg.

This includes the following highways...
	Interstate 295 in New Jersey between mile markers 66 and 76.
	New Jersey Turnpike near exit 9.
	Garden State Parkway between mile markers 112 and 120.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

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

&&

LAT...LON 4036 7479 4035 7476 4041 7428 4045 7422
      4044 7421 4046 7414 4040 7398 4048 7401
      4044 7398 4038 7388 4024 7483 4030 7487
      4034 7494 4039 7496 4041 7479

FLASH FLOOD...RADAR INDICATED
FLASH FLOOD DAMAGE THREAT...CONSIDERABLE
EXPECTED RAINFALL RATE...1-3 INCHES IN 1 HOUR

$$

Kruzdlo
569 
WGUS71 KPHI 182247
FFSPHI

Flash Flood Statement
National Weather Service Mount Holly NJ
647 PM EDT Sat Jul 18 2026

NJC019-021-023-025-182257-
/O.EXP.KPHI.FF.W.0049.000000T0000Z-260718T2245Z/
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/
Hunterdon NJ-Mercer NJ-Middlesex NJ-Monmouth NJ-
647 PM EDT Sat Jul 18 2026

...FLASH FLOOD WARNING HAS EXPIRED FOR NORTHEASTERN MERCER, 
NORTHWESTERN MONMOUTH, SOUTHWESTERN MIDDLESEX AND SOUTHEASTERN 
HUNTERDON COUNTIES...

This Flash Flood Warning that covered multiple counties has expired. 
We are still receiving flooding reports from earlier rain in 
Monmouth County and a Flood Warning will issued for this shortly.

A Flood Watch remains in effect until 200 AM EDT Sunday for portions 
of northern Delaware, New Jersey, and Pennsylvania.

&&

LAT...LON 4036 7479 4035 7476 4041 7428 4045 7422
      4044 7421 4046 7414 4040 7398 4048 7401
      4044 7398 4038 7388 4024 7483 4030 7487
      4034 7494 4039 7496 4041 7479

$$

Kruzdlo

The office that day

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

IssuedProductOfficeCountiesLasted
Jul 18, 10:39 AM EDTSevere Thunderstorm WarningPHISussex, Warren21 min
Jul 18, 12:40 PM EDTFlash Flood WarningPHIMiddlesex, Morris, Somerset3 hr
Jul 18, 1:52 PM EDTFlash Flood WarningPHIMercer, Middlesex, Somerset4 hr
Jul 18, 3:13 PM EDTSevere Thunderstorm WarningPHIBurlington, Mercer, Middlesex, Monmouth, Ocean47 min
Jul 18, 3:14 PM EDTFlash Flood Warning Considerable damage threatPHIMercer4 hr
Jul 18, 3:16 PM EDTSpecial Marine WarningPHI59 min
Jul 18, 3:30 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden45 min
Jul 18, 3:31 PM EDTSevere Thunderstorm WarningPHIBurlington, Monmouth, Ocean44 min
Jul 18, 3:36 PM EDTSevere Thunderstorm WarningPHIBurlington, Camden, Gloucester39 min
Jul 18, 3:44 PM EDTFlash Flood WarningPHIMiddlesex, Monmouth, Ocean4 hr
Jul 18, 4:02 PM EDTSpecial Marine WarningPHI118 min
Jul 18, 4:03 PM EDTSevere Thunderstorm WarningPHIBurlington, Ocean42 min
Jul 18, 4:34 PM EDTFlash Flood WarningPHIOcean4 hr
Jul 18, 4:46 PM EDTFlash Flood WarningPHIOcean4 hr
Jul 18, 5:14 PM EDTSevere Thunderstorm WarningPHICumberland, Salem61 min
Jul 18, 5:16 PM EDTSpecial Marine WarningPHI89 min
Jul 18, 5:47 PM EDTSpecial Marine WarningPHI118 min
Jul 18, 5:49 PM EDTSevere Thunderstorm WarningPHIMonmouth, Ocean41 min
Jul 18, 6:30 PM EDTSpecial Marine WarningPHI2 hr
Jul 18, 6:30 PM EDTSevere Thunderstorm WarningPHIMercer, Middlesex, Monmouth, Somerset45 min
Jul 18, 6:55 PM EDTAreal Flood WarningPHIMonmouth4 hr
Jul 18, 6:56 PM EDTSpecial Marine WarningPHI64 min
Jul 18, 7:13 PM EDTSevere Thunderstorm WarningPHICape May32 min
Jul 18, 7:47 PM EDTAreal Flood WarningPHIMonmouth, Ocean4 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; local storm reports from the same archive; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.