The New York Times reported that there have been at least seven storm-related deaths in the city itself, while neighboring New Jersey has seen two deaths. Ida, now a tropical storm, walloped the region with several inches of rain and triggered tornadoes in Maryland and New Jersey. At one point, the rain was so heavy that New York’s Central Park received 3.15 inches (8 cm) of rain in one hour Wednesday evening, about what it normally gets in three weeks, breaking an hourly record of 1.9 inches set just days before when Tropical Storm Henri came through the region.

Twitter was full of videos of the storm: Waterfalls cascaded down staircases in New York City subway stations, and cars floated down streets throughout the region in scenes reminiscent of the chaos brought by Hurricane Sandy in 2012, which flooded and destroyed parts of the subway system.

“We’re enduring a historic weather event tonight with record-breaking rain across the city, brutal flooding, and dangerous conditions on our roads,” de Blasio said in a tweet. New York Gov. Kathy Hochul and New Jersey Gov. Phil Murphy have also declared states of emergency.

The National Weather Service issued a Flash Flood Emergency for New York City and northeast New Jersey on Wednesday, which it said was the the first it had ever issued for the region. The flood comes on the heels of an unusually wet August in the area that included a number of big rainfalls in addition to Tropical Storm Henri, making it even harder for the soil and sewage system to handle all the rain. Parts of New York City remained under flood advisories early Thursday morning even though the rain has ended.

Ida has left a trail of destruction in its wake elsewhere in the United States: On Sunday, it slammed into Louisiana as a Category 4 hurricane with record 150 mph (241 kph) winds. Hundreds of thousands of people in New Orleans are still without electricity.

The calamity is sure to reignite debate about climate change as the latest example of extreme weather this summer that has included record heat in Canada, and wildfires from California to Greece to Siberia.

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