The city of New York declared a state of emergency this week due to “brutal flooding” after being caught by the tail end of Hurricane Ida.

The National Weather Service (NSW) also issued its first ever flash flood warning in the city as streets, subway stations and airports were inundated.

At least 45 people were feared dead after storm Ida dumped record levels of rain in parts of New York and New Jersey, causing widespread flooding.

New York was placed on tornado watch on Wednesday night (1 September) after the area was hit by the remnants of tropical storm Ida.

Announcing the state of emergency at 11.30pm local time, mayor Bill de Blasio wrote: “We’re enduring an historic weather event tonight with record breaking rain across the city, brutal flooding and dangerous conditions on our roads. Please stay off the streets… 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.”

He added: “We’re keeping our eyes on our power grid. We’ve seen about 5,300 customers without power.”

New Jersey and Pennsylvania have also been hit by torrential rain and strong winds, with at least one tornado collapsing the roof of a US Postal Service building and threatening to overrun a dam on the way.

Governor Phil Murphy declared a state of emergency in all of New Jersey’s 21 counties, urging people to stay off the flooded roads.

The NWS confirmed that a tornado had struck and issued a flood warning to New York residents.

The service wrote on Twitter that “this particular warning for NYC is the second time we’ve ever issued a Flash Flood Emergency (It’s the first one for NYC)”

It added: “The first time we’ve issued a Flash Flood Emergency was for Northeast New Jersey an hour ago”.

The weather also forced a suspension in play at the US Open when a night match had to be halted, despite it being played under a roof.

Play between Kevin Anderson and Diego Schwartzman inside the Louis Armstrong Stadium was stopped after the torrential rain began blowing in sideways through openings under the roof.

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