At least 9 reported dead in 'historic' flooding in New York, New Jersey

Flooding killed at least nine people, swept away cars, submerged subway lines and grounded flights in New York and New Jersey as the remnants of Hurricane Ida brought torrential rains to the area.

New York City Mayor Bill de Blasio described the flooding and weather on Wednesday night as a "historic weather event," and the National Weather Service issued a flash flood emergency in New York City for the first time.

Recovery efforts were underway early on Thursday to bring back transportation systems serving millions of residents in the densely populated metropolitan area.

New York Governor Kathy Hochul urged commuters to stay home from work and pleaded for patience to "give us some time to have complete restoration of the trains" after service was knocked out in much of the area, leaving many riders stranded overnight.

"This is one for the record books," Hochul told CNN.

The storm dumped "extreme rain rates" of 2 to 3 inches (5 to 7.6 cm) per hour along the Philadelphia to New York City corridor, the National Weather Service said.

Subway service in New York City remained "extremely limited" on Thursday morning, the Metropolitan Transit Authority (MTA) said. Janno Lieber, the MTA's acting chair and CEO told local media it was going to take until later in the day to restore full service.