A developing area of low pressure along a surface trough helped produce heavy rainfall across parts of northeast New Jersey on the morning of August 4th that resulted in flash flooding. Rainfall amounts ranged from 1-3 inches in many places. Between the afternoon of August 3rd and the afternoon of August 4th, the Caldwell, NJ ASOS measured 2.75, and CoCoRaHS observers in Park Ridge and Hawthorne measured 2.90 and 2.95, respectively, with a CWOP station in Scotch Plains reporting 2.42.

Flash Flood in UNION, NEW JERSEY
From 04-AUG-18 08:28:00 to 04-AUG-18 09:17:00 (EST-5)
Location: BERKELEY HGTS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Flooding closed all westbound lanes of US Route 22 in Scotch Plains at the intersection with Bonnie Burn Road and Park Avenue.

Flash Flood in UNION, NEW JERSEY
From 04-AUG-18 08:45:00 to 04-AUG-18 09:17:00 (EST-5)
Location: NEW PROVIDENCE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Both lanes of Division Avenue in Summit were closed due to flooding.

Flash Flood in ESSEX, NEW JERSEY
From 04-AUG-18 08:47:00 to 04-AUG-18 09:17:00 (EST-5)
Location: WHITEOAK RIDGE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

Old Short Hills Road was closed due to flooding in Millburn.

Flood in BERGEN, NEW JERSEY
From 04-AUG-18 09:56:00 to 04-AUG-18 10:26:00 (EST-5)
Location: HILLSDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Broadway closed between Lake Street and Lawrence Street along the Westwood/Hillsdale town line. In addition, the Pascack Brook was over its banks in Hillsdale, with flooding near the Hillsdale train station and several nearby parking lots and streets.

Flash Flood in BERGEN, NEW JERSEY
From 04-AUG-18 06:00:00 to 04-AUG-18 12:30:00 (EST-5)
Location: RIDGEWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Hohokus Brook at Ho-Ho-Kus rose above its flood stage of 3.0 feet at 7:00am EDT, crested at a height of 4.15 feet at 7:45am EDT, and fell back below flood stage at 1:30pm EDT.

Flash Flood in BERGEN, NEW JERSEY
From 04-AUG-18 09:45:00 to 04-AUG-18 13:45:00 (EST-5)
Location: HILLSDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Pascack Brook at Westwood rose above its flood stage of 5.0 feet at 10:45am EDT, crested at a height of 5.34 feet at 12:45pm EDT, and fell back below flood stage at 2:45pm EDT.

Flash Flood in BERGEN, NEW JERSEY
From 04-AUG-18 08:15:00 to 04-AUG-18 09:00:00 (EST-5)
Location: WOODCLIFF LAKE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Pascack Brook at Park Ridge rose above its flood stage of 5.2 feet at 9:15am EDT, crested at a height of 5.29 feet at 9:30am EDT, and fell back below flood stage at 10:00am EDT.

Flash Flood in BERGEN, NEW JERSEY
From 04-AUG-18 09:00:00 to 04-AUG-18 11:00:00 (EST-5)
Location: WESTWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: River/Stream Gage

The Saddle River at Ridgewood rose above its flood stage of 5.0 feet at 10:00am EDT, crested at a height of 5.41 feet at 11:15am EDT, and fell back below flood stage at 12:00pm EDT.