An inverted trough extending from a low pressure system over the Western Atlantic provided a focus for persistent heavy convective rain to continually develop over the NYC metro and surrounding areas during much of the day on September 29th, 2023. In an environment with anomalously high moisture given the time of year, PWATs near 1.5-1.7 inches, rounds of heavy rainfall fell over the same areas for more than 12-18 hours. While the rainfall rates were generally 1 inch per hour or less, the persistence in the heavier rainfall resulted in a widespread total of 4-6 inches of rain with JFK receiving almost 9 inches of rain from the event. There were some brief periods of time where rainfall rates peaked at near 2 inches per hour. This resulted in widespread flash flooding across Southeast NY and Southern Connecticut.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 13:56:00 to 29-SEP-23 14:26:00 (EST-5)
Location: HEWLETT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Several Cars Stranded in flood waters with rescues Underway on Peninsula Blvd near Woodmere Blvd.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:06:00 to 29-SEP-23 14:36:00 (EST-5)
Location: NORTH VLY STREAM
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Hempstead Turnpike closed in both directions between Holland and Plainfield Ave. All lanes are blocked due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:10:00 to 29-SEP-23 14:40:00 (EST-5)
Location: EAST WILLISTON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Shelter Rock Road at Searingtown Road is closedu in both directions due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:46:00 to 29-SEP-23 15:16:00 (EST-5)
Location: SOUTH HEMPSTEAD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Motorist Stranded in flood waters on N Centre Ave. Fire department responding for water rescue.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:56:00 to 29-SEP-23 15:26:00 (EST-5)
Location: BELLMORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Multiple motorists stuck in flood waters on Linden Street. Fire Department responding with water rescue vehicles.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:53:00 to 29-SEP-23 15:23:00 (EST-5)
Location: HEWLETT
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Motorist stuck in flood waters on Island Ave in Woodmere. Fire Department responding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 15:00:00 to 29-SEP-23 15:30:00 (EST-5)
Location: JERICHO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Submerged vehicle in flood waters on Richmond Ave. Fire department responding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 15:15:00 to 29-SEP-23 15:45:00 (EST-5)
Location: JERICHO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Northern State Parkway westbound at Exit 34 is closed due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 15:17:00 to 29-SEP-23 15:47:00 (EST-5)
Location: NORTH BELLMORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report from mPing of vehicles stranded in flooded roadways.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:16:00 to 29-SEP-23 14:46:00 (EST-5)
Location: NEW CASSEL
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reports from mPing of vehicles stranded in flooded roadways.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:01:00 to 29-SEP-23 14:31:00 (EST-5)
Location: SOUTH HEMPSTEAD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report from mPing of vehicle stranded in flood waters.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 13:59:00 to 29-SEP-23 14:29:00 (EST-5)
Location: BELLMORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public report from mPing of vehicle stranded in flood waters.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 07:30:00 to 29-SEP-23 08:00:00 (EST-5)
Location: CONEY IS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Vehicle stranded in flood waters at the intersection of Belt Parkway and Cropsey Avenue. Belt Parkway is closed in both directions.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 15:36:00 to 29-SEP-23 16:06:00 (EST-5)
Location: NORTH BELLMORE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Multiple vehicles stuck in flood waters. Fire Department responding.

Flash Flood in SUFFOLK, NEW YORK
From 29-SEP-23 15:47:00 to 29-SEP-23 16:17:00 (EST-5)
Location: WYANDANCH
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

NY 110 at Conklin Street in Farmingdale is closed due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 16:16:00 to 29-SEP-23 16:46:00 (EST-5)
Location: JERICHO
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Westbound lanes of Northern State Parkway are closed due to flooding at Exit 35 S.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 07:35:00 to 29-SEP-23 08:05:00 (EST-5)
Location: CONEY IS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

David A Boody School is flooded and being evacuated.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 07:38:00 to 29-SEP-23 08:08:00 (EST-5)
Location: BROOKLYN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Car stranded in flood waters at the intersection of Prospect Avenue and Caton Avenue.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 07:43:00 to 29-SEP-23 08:13:00 (EST-5)
Location: BROOKLYN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Multiple cars stranded in flood waters at the intersection of Prospect Expressway and Caton Avenue.

Flash Flood in SUFFOLK, NEW YORK
From 29-SEP-23 15:25:00 to 29-SEP-23 15:55:00 (EST-5)
Location: HALESITE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

NY 110 is closed due to flooding between Mill Lane and Prime Avenue and near Madiosn Street at Heckscher Park.

Flash Flood in SUFFOLK, NEW YORK
From 29-SEP-23 16:37:00 to 29-SEP-23 17:07:00 (EST-5)
Location: COMMACK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Fire Department/Rescue

Motorist stranded on Town Line Road. Dire Department responding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 16:00:00 to 29-SEP-23 16:30:00 (EST-5)
Location: NORTH MERRICK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

Meadow Brook Parkway closed in both directions at Exit M7 due to flooding.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 08:02:00 to 29-SEP-23 08:32:00 (EST-5)
Location: CORONA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Department of Highways

DOT reports flooding on runway drive both directions. 94th Street to Marine Terminal Road. All lanes closed and detoured.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 08:05:00 to 29-SEP-23 08:35:00 (EST-5)
Location: FOREST HILLS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Other Federal Agency

FAA reports LGA Airport fuel farm flooded and unusable.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 08:15:00 to 29-SEP-23 08:45:00 (EST-5)
Location: BROOKLYN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Water rescues on Prospect expressway at Caton Avenue. Fire department responding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 13:53:00 to 29-SEP-23 14:23:00 (EST-5)
Location: QUARRY HGTS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Metro North tracks at the Valhalla station flooded with water covering the tracks.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 11:00:00 to 29-SEP-23 11:30:00 (EST-5)
Location: LARCHMONT NORTH
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Widespread flooding across the town with multiple roads closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 13:30:00 to 29-SEP-23 14:00:00 (EST-5)
Location: CHAPPAQUA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Newspaper

Route 117 closed due to flooding between Orchard Road and North Way.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 08:30:00 to 29-SEP-23 09:00:00 (EST-5)
Location: BROOKLYN
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Multiple car stranded with water up to the windows on Prospect Expressway at Exit 5.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 08:34:00 to 29-SEP-23 09:04:00 (EST-5)
Location: CORONA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Runway Drive between Marine Terminal Road and 94th Street closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 08:37:00 to 29-SEP-23 09:07:00 (EST-5)
Location: HAWTHORNE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Taconic State Parkway closed in both directions between Stevens Ave and Cleveland Street due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:57:00 to 29-SEP-23 15:27:00 (EST-5)
Location: EAST ROCKAWAY
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWSS

Long Island Railroad service on the Long Beach Branch suspended due to flooding between Lynbrook and Long Beach.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 14:02:00 to 29-SEP-23 14:32:00 (EST-5)
Location: CEDARHURST
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWSS

Long Island Railroad service suspended on the Far Rockaway Branch between Valley Stream and Far Rockaway due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 08:37:00 to 29-SEP-23 09:07:00 (EST-5)
Location: HAWTHORNE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

DOT reports flooding on the Taconic State Parkway both directions between Stevens AVe and Commerce Street. All 3 lanes closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 08:52:00 to 29-SEP-23 09:22:00 (EST-5)
Location: TUCKAHOE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hutchinson River Parkway closed in both directions between Exit 8 and Bronx-Westchester County Line.

Flash Flood in BRONX, NEW YORK
From 29-SEP-23 08:54:00 to 29-SEP-23 09:24:00 (EST-5)
Location: HARLEM RIVER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWSS

Six line NYC Subway service suspended in the Bronx Due to heavy  flooding at several subway stations.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 09:00:00 to 29-SEP-23 09:30:00 (EST-5)
Location: CORONA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

All westbound lanes closed on the Grand Central Parkway at 86th street.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 09:01:00 to 29-SEP-23 09:31:00 (EST-5)
Location: EAST CHESTER
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

North Ave closed due to flooding between City Hall and Iona University.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 09:04:00 to 29-SEP-23 09:34:00 (EST-5)
Location: CORONA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

LaGuardia Terminal A closed due to flooding inside the building from heavy rain.

Flash Flood in KINGS, NEW YORK
From 29-SEP-23 09:15:00 to 29-SEP-23 09:45:00 (EST-5)
Location: NEW YORK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

All lanes of I-278 at Grand Street East and West bound are blocked due to flooding.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 09:15:00 to 29-SEP-23 09:45:00 (EST-5)
Location: CORONA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

All lanes blocked due to flooding on the Grand Central Parkway westbound at 86th Street.

Flash Flood in QUEENS, NEW YORK
From 29-SEP-23 09:15:00 to 29-SEP-23 09:45:00 (EST-5)
Location: LITTLE NECK
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Cross Island Parkway Ramp for northbound traffic closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 09:42:00 to 29-SEP-23 10:12:00 (EST-5)
Location: ELMSFORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Saw Mill River Parkway closed in both directions between exit I-287 and Exit 20 due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 09:48:00 to 29-SEP-23 10:18:00 (EST-5)
Location: EAST VIEW
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Route 9A closed in both directions at Old Country Road in Greenburgh due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 09:52:00 to 29-SEP-23 10:22:00 (EST-5)
Location: ELMSFORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

NY 9 both directions south of West Main Street closed due to flooding.

Flash Flood in ROCKLAND, NEW YORK
From 29-SEP-23 09:59:00 to 29-SEP-23 10:29:00 (EST-5)
Location: VIOLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

DOT reports flooding and road closure on NY 306 both directions at Edison Court. All lanes closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 10:08:00 to 29-SEP-23 10:38:00 (EST-5)
Location: MT VERNON
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Bronx River Parkway closed at Oak Street. All 6 lanes closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 11:51:00 to 29-SEP-23 12:21:00 (EST-5)
Location: YONKERS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Bronx River Parkway closed at Cross County Parkway due to flooding. All lanes closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 10:14:00 to 29-SEP-23 10:44:00 (EST-5)
Location: ELMSFORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Srain Brook Parkway closed between the start route of the Sprain Brook Parkway and Exit for NY 100. All lanes closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 10:19:00 to 29-SEP-23 10:49:00 (EST-5)
Location: YONKERS
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Bronx River Parkway closed at Cross County Parkway due to flooding. All lanes closed.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 10:14:00 to 29-SEP-23 10:44:00 (EST-5)
Location: TUCKAHOE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Sprain Brook Parkway closed between start route of the Sprain Brook Parkway and Exit for NY 100. All lanes closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 10:09:00 to 29-SEP-23 10:39:00 (EST-5)
Location: TUCKAHOE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Bronx River Parkway between Sprain Brook Parkway and Exit 22 closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 11:53:00 to 29-SEP-23 12:23:00 (EST-5)
Location: FLEETWOOD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Cross County Parkway Eastbound ramp of Exit 9 closed due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 12:02:00 to 29-SEP-23 12:32:00 (EST-5)
Location: TUCKAHOE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Hutchinson River Parkway closed in both directions at Exit 9A and 9B due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 11:55:00 to 29-SEP-23 12:25:00 (EST-5)
Location: EAST VIEW
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Saw Mill River Parkway closed in both directions between Exit 23 and Old Saw Mill Road due to flooding.

Flash Flood in WESTCHESTER, NEW YORK
From 29-SEP-23 11:35:00 to 29-SEP-23 12:05:00 (EST-5)
Location: VALHALLA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Spraine Brook Parkway at Exit CR 301 closed due to flooding.

Flash Flood in NASSAU, NEW YORK
From 29-SEP-23 13:45:00 to 29-SEP-23 14:15:00 (EST-5)
Location: NORTH VLY STREAM
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Southern State Parkway Eastbound at Exit 13 closed due to flooding. All lanes closed.