At least six people have been killed after Storm Ida dumped a month’s worth of rain on parts of the US.

Four of those who died were in New York City, while the other two were in New Jersey, according to NBC.

A state of emergency has been declared after the remnants of a hurricane sparked flash floods, with subway services suspended.

Last night, New York City suffered its wettest hour on record, with more than 80mm of rain falling in Central Park in the space of 60 minutes.

That eclipsed the previous record of 49mm that was set in the aftermath of Tropical Storm Henri just last month.

Parts of New Jersey and Connecticut are also under a flash flood warning.

The National Weather Service’s New York City Twitter account said: “This emergency was issued due to the ongoing life threatening flash flooding.

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The heaviest rain has pushed east of the Flash Flood Emergency area, with more moderate rainfall the next few hours.”

Flights in and out of Newark airport have been cancelled, and there was widespread disruption on railways.

Newark Liberty Airport’s Twitter account said: “We’re experiencing severe flooding due to tonight’s storm.

“All flight activity is currently suspended and travellers are strongly advised to contact their airline for the latest flight and service resumption information.

“Passengers are being diverted from ground-level flooded areas.”

Announcing a state of emergency, New York City mayor Bill de Blasio said: “I’m declaring a state of emergency in New York City tonight.

“We’re enduring a historic weather event tonight with record-breaking rain across the city, brutal flooding and dangerous conditions on our roads.

“Please stay off the streets tonight and let our first responders and emergency services get their work done.

“If you’re thinking of going outside, don’t. Stay off the subways. Stay off the roads. Don’t drive into these heavy waters.

“Stay inside.”