The death toll caused by Hurricane Ida continued to rise on Sunday, with many in the U.S. Northeast holding out hope for people missing in the floodwaters, while in Louisiana nearly 600,000 residents still lacked power a week after the storm made landfall.

Ida slammed into Louisiana on August 29 as a Category 4 hurricane with sustained winds of 150 miles per hour (240 kilometers per hour), and the latest death toll there rose to at least 13 by Sunday.

The storm weakened as it moved north but still unleashed flash flooding on the East Coast that killed at least 50 more people, according to updated numbers on Sunday.

"Human toll was tremendous"

Ida's record-breaking rainfall of 3.1 inches (7.8 centimeters) per hour on Wednesday, recorded in New York City's Central Park, sent walls of water cascading through businesses, public transportation systems and 1,200 homes, causing more than $50 million in damages, New York's governor Kathy Hochul said.

"The human toll was tremendous," said Hochul, recounting a trip to East Elmhurst in the city borough of Queens to assess the devastation.

"One woman wept in my arms, an 89-year-old woman. She had nothing left after living in that home for over 40 years," Hochul said.

Hochul had previously secured an emergency disaster declaration from President Joe Biden and on Sunday signed paperwork to request related federal money to cover the costs of temporary housing as well as rebuilding homes, possibly in less flood-prone locations.

New York had 17 confirmed deaths, four in Westchester County and the remainder in New York City, where nearly all the victims were trapped in illegal basement apartments that are among the last remaining affordable options for low-income residents in the area, the governor's spokesperson said.

In New Jersey, there were 27 confirmed storm deaths and four people still missing, said a spokesperson for Governor Phil Murphy.

Restoring power underway

Amid stifling heat and humidity, more than 591,000 homes and businesses lacked electricity as of Sunday, according to PowerOutage.US. Some 1.2 million had originally lost power.

Ida also paralyzed U.S. Gulf of Mexico oil production, and 88 percent of crude oil output and 83 percent of natural gas production remained suspended as of Sunday.

The Grand Classica, a cruise ship that will house 1,500 workers trying to restore power, departed from the Port of Palm Beach on Saturday and is due to arrive in New Orleans on Tuesday under a charter agreement with Entergy Corp., the Bahamas Paradise Cruise Line said.

A massive oil slick has emerged near the oil hub of Port Fourchon, with satellite images showing a miles-long brownish-black slick spreading in the coastal waters. A private dive team was attempting to locate the source.