The National Weather Service (NWS) has issued its first ever flash flood warning for the city of New York, as the remnants of Hurricane Ida brought heavy rain that flooded subway lines and streets in Manhattan, Brooklyn and New Jersey.

Amid the downpour, the service said on Twitter, “this particular warning for NYC is the second time we’ve ever issued a Flash Flood Emergency (It’s the first one for NYC). The first time we’ve issued a Flash Flood Emergency was for Northeast New Jersey an hour ago.”

The storm killed one person in New Jersey, according to the Washington Post.

New York mayor Bill de Blasio declared a state of emergency shortly before midnight on Wednesday, saying “We’re enduring an historic weather event tonight with record breaking rain across the city, brutal flooding and dangerous conditions on our roads.”

De Blasio declared a state of emergency at about 11:30pm and said thousands of New Yorkers had lost power.

The NWS recorded 3.15 inches of rain in Central Park in one hour, far surpassing the 1.94 inches that fell in one hour during Tropical Storm Henri on the night of 22 August, which was believed at the time to be the most ever recorded in the park.

Heavy winds, drenching rains and at least one tornado also battered Pennsylvania and New Jersey, collapsing the roof of a US Postal Service building and threatening to overrun a dam on the way.

The NWS confirmed at least one tornado and social media posts showed homes reduced to rubble in Mullica Hill, a southern New Jersey county just outside Philadelphia.

The Port Authority of New York and New Jersey, which operates Newark Liberty International Airport, tweeted at 10:30pm that all flights were suspended and all parking lots were closed due to severe flooding. All train service to the airport also was suspended.

Video showed parts of the airport flooded with water.

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 Metropolitan Train Authority announced that services would be “extremely limited tonight because of heavy rainfall and flooding across the region” and “strongly” recommended that commuters avoid travel if possible.

With Associated Press