Flash flood warning issued as storms bear down on NYC and Long Island

More than 60 million people from Ohio to Massachusetts and Virginia are bracing for possible flash flooding on Monday following a deadly holiday weekend heat wave that left much of the East Coast sweltering in triple-digit temperatures.

New York City and Long Island appear to be in the center of the storm zone, with a level 3 out of 4 threat for flash flooding. Southern Connecticut, Rhode Island and southeast Massachusetts are also expected to get heavy rain.

Up to 3 inches of rain per hour is possible in some parts of the Northeast, and some areas could receive up to 8 inches.

A flood watch is in effect for the entire New York City metropolitan area through Monday night. A flash flood warning was issued on Monday for the New York City boroughs of Brooklyn and Queens, where 1 to 2 inches of rain had already fallen on Monday morning.

A flash flood warning has also been issued for more than 2.5 million people in the Philadelphia area, where flooding was already reported Monday, including in the Lemon Hill Park neighborhood in North Philadelphia.

New York City Mayor Zohran Mamdani released an online video statement on Sunday, advising New Yorkers to take precautions.

“We ask New Yorkers in this time to stay safe, stay prepared, and to keep an eye out for one another,” said Mamdani, adding that city workers were out over the weekend clearing catch basins and preparing neighborhoods that are historically flood-prone for the impending storm.

The mayor asked New Yorkers who live in basement apartments to plan to evacuate.

“If you see water rising around you, move to higher ground,” Mamdani said.

In Ocean Township, New Jersey, severe weather likely caused the roof of a BJ’s Wholesale Club to partially collapse while 27 people were inside the store, according to Monmouth County Sheriff Michael Sorrentino.

Sorrentino said the incident occurred around 11:16 a.m. He said two people were partially entrapped but managed to free themselves and safely exit the business. He said no injuries were reported.

“This incident is another reminder of how quickly severe weather can create dangerous and unpredictable conditions,” Sorrentino said in a statement.

Meanwhile, more than 700 flights have been canceled as of 2:30 p.m ET at New York and New Jersey airports due to the severe weather.

All major airports in the New York region were seeing flight delays of more than an hour due to thunderstorms, with ground stops being issued by the Federal Aviation Administration throughout the day.

Flights out of Ronald Reagan Washington National Airport and Philadelphia International Airport were also seeing flight delays due to thunderstorms.

The storms expected on Monday follow a multi-day heat wave. Parts of the mid-Atlantic and South saw heavy rain on Sunday night.

At one point, more than 800,000 utility customers from Oklahoma to Connecticut lost electricity on Sunday, including 85,000 in New York, according to the website PowerOutage.com.

In New Jersey, Gov. Mikie Sherrill said that thunderstorms on Friday night and over the weekend knocked out power to nearly 300,000 utility customers and that wind gusts of up to 80 mph toppled trees and power lines.

At least 25 people are suspected to have died in New Jersey from the sweltering heat wave that had enveloped a large portion of the country, officials said.

At least 60,424 utility customers in New Jersey, 43,664 in New York, more than 95,000 across Pennsylvania and at least 100,000 in Michigan remained without power on Monday morning, according to PowerOutage.com.

New Jersey Health Commissioner Dr. Raynard Washington told reporters at the news conference on Saturday that many of the people who perished in the heat in New Jersey were found in homes without air conditioning.