Irma, one of the most powerful Atlantic hurricanes on record, was downgraded to a tropical depression on Monday. It will likely dissipate from Tuesday evening, the National Hurricane Center said.

Local authorities told around 90,000 residents of Miami Beach and from some parts of Florida Keys they could go home but warned it may not be prudent to remain there.

“Returning residents should consider that there are limited services. Most areas are still without power and water. Cell service is spotty. And most gas stations are still closed,” the Monroe County of Board of County Commissioners said in a posting on its Facebook page.

After leaving a trail of destruction on several Caribbean islands, killing nearly 40 people, Irma caused record flooding in parts of Florida. Only one fatality has been confirmed so far, but a local official said there had been more deaths.

The U.S. aircraft carrier Abraham Lincoln has arrived off Florida’s east coast and two amphibious assault ships will arrive on Tuesday to help in the Keys, where Irma first made landfall on Sunday as a Category 4 hurricane.

The U.S. Department of Defense said the military will distribute food and help evacuate 10,000 Keys residents who did not leave before the storm.

Heather Carruthers, the Monroe County Commissioner, said people had been killed in the archipelago, where nearly 80,000 permanent residents live, apart from one already known fatality. She did not have a count on how many.

“We are finding some remains,” she said in an interview with CNN. Video footage of the islands showed homes torn apart by sustained winds of up to 130 mph (210 kph).

Several major airports in Florida that halted passenger operations due to Irma began limited service on Tuesday, including Miami International, one of the busiest U.S. airports. Thousands of flights had to be canceled.

Still, the scope of damage in Florida and neighboring states paled in comparison with the devastation left by Irma as a Category 5 hurricane, the rare top end of the scale of hurricane intensity, in parts of the Caribbean. Of the nearly 40 dead, at least 10 were killed in Cuba.

Record Floods

The center of Irma moved into Alabama on Tuesday and will head into western Tennessee by Tuesday evening with maximum sustained winds of 25 mph.

In South Carolina, the Charleston Harbor area saw major flooding on Monday with water about 3 feet (1 meter) above flood stage and minor flooding is forecast for Tuesday, the National Weather Service said.

In Florida, 51 of 178 gauges in the state were at flood stages on Monday with some of the worst floods in Jacksonville, in the northeastern part of the state. The waters are forecast to recede on Tuesday but will still be above flood stages, the service said.

Coast Guard teams used small boats to rescue more than 100 people from flooded neighborhoods in Jacksonville.

Especially hard hit in the United States was the resort archipelago of the Keys, extending into the Gulf of Mexico from the tip of Florida’s peninsula and connected to the mainland by a single, narrow highway, Governor Rick Scott told a news conference on Monday.

“There’s devastation,” he said, adding that virtually every mobile-home park on the island chain was left upended. “It’s horrible what we saw.”

More evacuation orders were likely to be lifted on Tuesday. Miami Beach will allow residents to return home from 8 a.m. (1200 GMT), its mayor said.

Monroe County would reopen road access on Tuesday morning at 7 a.m. EDT (1100 GMT) for residents and business owners from Key Largo, the main island at the upper end of the chain, as well as the towns of Tavernier and Islamorada farther to the south, fire officials said.

No timetable for reopening the remainder of the Keys was given.

The Keys were largely evacuated before the storm struck and police established a checkpoint on Monday to keep displaced residents from returning while authorities worked to restore basic services.

Most of Florida Without Electricity

Insured property losses in Florida from Irma are expected to run from $20 billion to $40 billion, catastrophe modeling firm AIR Worldwide estimated. This has helped spur a rally on Wall Street as fears eased that Irma would cut into U.S. economic growth.

Utilities reported some 7.4 million homes and businesses were without electricity in Florida and neighboring states and said it could take weeks to fully restore service.

Scott said 65% of Florida was without power.

Between 2,000 and 3,000 utility workers from out of state, sent to inspect and repair power lines, were staying in cramped conditions at BB&T Center in Broward County, home to the National Hockey League’s Florida Panthers, said Gus Beyersdorf, 40, of De Pere, Wisconsin.

“Each one of us has a cot, a single foot apart,” Beyersdorf said on Monday afternoon. “I slept in the truck last night just to get a break from it.”

Irma’s arrival in Florida came around two weeks after Hurricane Harvey claimed about 60 lives and caused property damage estimates as high as $180 billion after pummeling the Gulf Coasts of Texas and Louisiana with heavy rains and severe flooding.

The storm claimed its first known U.S. fatality over the weekend in the Keys—a man found dead in a pickup truck that had crashed into a tree in high winds.

At least one other possibly storm-related fatal car crash was reported on Sunday in Orange County, Florida. On Monday, two people were killed by falling trees in two Atlanta suburbs, according to local authorities.