New Yorkers mopped up flooded homes and businesses and began removing fallen debris from crushed cars Thursday as they counted the cost of record rainfall that caught much of the Big Apple by surprise.

Under piercing blue skies that belied the carnage of just a few hours earlier, shocked residents surveyed the damage of a chaotic night that left at least nine people dead in the city and killed several more in outlying areas.

"I honestly feel heartbroken," said Marcio Rodrigues, at his destroyed car repair shop in the New York suburb of Mamaroneck, where several clients' cars were ruined.

A motorist drives a car through a flooded expressway in Brooklyn, New York early on September 2, 2021, as flash flooding and record-breaking rainfall brought by the remnants of Storm Ida swept through the area
A motorist drives a car through a flooded expressway in Brooklyn, New York early on September 2, 2021, as flash flooding and record-breaking rainfall brought by the remnants of Storm Ida swept through the area AFP / Ed JONES

"This was my dream. And I feel like I lost it all right now," he told AFP, crying.

A short distance away, electrical contractor Jim Lanza's ground-floor office was full of mud after water rose 7-feet high.

"It's pretty devastating," he said, adding that the water took about seven hours to recede.

Record rainfall brought chaos to New York City roads in the early hours of September 2, 2021
Record rainfall brought chaos to New York City roads in the early hours of September 2, 2021 AFP / Ed JONES

Nearby, Jeannsie Silva Barrios recalled a sleepless night as the owner of her house pumped water from her basement.

"I was really scared. My husband had to wake up at like four o'clock in the morning just to see the water, how it was going," she said.

A few miles south, on Manhattan's Upper West Side, Jonas Sigle eyed the wreckage of his car outside his home.

"A ten-ton tree just fell on my car. My car's crushed. It's totaled," he told AFP.

A person sweeps up debris in the front of a brownstone after the extremely heavy rainfall from Hurricane Ida on September 2, 2021, in the Bronx borough of New York City
A person sweeps up debris in the front of a brownstone after the extremely heavy rainfall from Hurricane Ida on September 2, 2021, in the Bronx borough of New York City GETTY IMAGES NORTH AMERICA / David Dee Delgado

"Wow, this was just unbelievable," said his neighbor, Michael Price.

Record rainfall of 3.15 inches (80 millimeters) fell in Central Park in just an hour, breaking a record set last month during Tropical Storm Henri.

Nearby, Metodija Mihajlov inspected the basement of his restaurant, which was flooded with three inches of water late Wednesday.

A fallen tree is blocked off in Central Park following a night of heavy wind and rain from the remnants of Hurricane Ida on September 02, 2021 in New York City
A fallen tree is blocked off in Central Park following a night of heavy wind and rain from the remnants of Hurricane Ida on September 02, 2021 in New York City GETTY IMAGES NORTH AMERICA / SPENCER PLATT

"When the rain started to get bad, my guys called me and we decided to close the restaurant and turn off the electricity and everybody left," he said.

"I've never seen that much rain ever," added the 50-year-old. "It was like living in the jungle, like tropical rain.

"Luckily nothing was damaged. As soon as the rain stopped the water drained away," Mihajlov told AFP.

The flooding reignited memories of Hurricane Sandy, a more powerful storm that knocked out power for much of Manhattan and flooded subways in 2012.

Many residents posted videos on social media that showed water cascading down stairs and into apartments.

In Brooklyn, Rebecca Stronger was mopping up water from the basement and first floors of her veterinary clinic.

"We all show up, we all clean and we all get our job done," she told AFP.

Stronger said she expects more storms in the future as the surface layer of oceans warms due to climate change.

"Of course. Everybody knows (about) climate change. The world is exploding on so many different levels. I expect it to happen a lot," she added.

The New York Police Department said nine people had died, eight of them trapped in basements and one in a car.

They were aged between two and 86 and were found mostly in flooded locations in Queens.

"Our hearts ache for the lives lost in last night's storm," tweeted Mayor de Blasio, who declared a state of emergency late Wednesday.

"Please keep them and their loved ones in your thoughts today. They were our fellow New Yorkers and to their families, your city will be there for you in the days ahead," he added.