MIRAMAR, Fla. One of the most powerful Atlantic hurricanes ever weakened to a tropical storm as it barged toward northern Florida and Georgia early Monday, uprooting thousands of people and leaving a trail of darkness in its wake.

Irma, which at its peak was a Category 5 hurricane with 185 mph winds, has left more than 5.8 million people in Florida without power, according to the state Division of Emergency Management. Roughly 83 percent of Monroe County, which includes the Florida Keys and Everglades National Park, is in the dark.

The storm, which devastated the Caribbean last week, is expected to become a tropical depression by Tuesday, the National Hurricane Center said.

Irma first made landfall in the Lower Florida Keys a little after 9 a.m. on Sunday, bringing ferocious winds and intense rainfall to the small beachside towns. The storm then headed for Floridas southwestern coast, making landfall again at 3:35 p.m. on Marco Island and weakening to a Category 2 shortly thereafter.

Officials reported four storm-related deaths and urged Floridians to stay off the roads.

The sheriffs office for Monroe County, which includes the Florida Keys, said on Saturday that one man had died in a car crash during the storm. Separately, a Florida sheriffs deputy was helping supply an evacuation shelter in Hardee County when the vehicle she was driving crashed into one driven by a state prison employee, killing them both.

Even as the storms wrath began to subside, many parts of Florida were virtual ghost towns , with stores and restaurants closed and no gasoline available at stations. Shelters were packed with people seeking safety. Families who sought refuge in hotels sat in the lobbies playing games with their children to keep their minds off what might be happening to their homes.

An estimated 208,000 people across six states, as well as Puerto Rico and the U.S. Virgin Islands, stayed in shelters on Sunday night, the Red Cross told HuffPost. Around 200,000 of those people were in Florida alone.

Nearly 7 million people from multiple states in the storms path were told to evacuate their homes, according to The Associated Press .

Meanwhile, residents in the Caribbean have begun the slow and painful process of rebuilding their lives after Irma devastated the region last week, leaving at least 38 people dead and almost completely destroying some islands.

Travis Waldron, David Lohr and Sebastian Murdock contributed reporting from Florida. Alana Horowitz, Lydia OConnor, Hayley Miller, Hilary Hanson, Carla Herreria, Nick Robins-Early, Peter Finocchiaro and Lee Moran also contributed to this report.

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