At least two deaths were blamed on the extreme storm front – the most powerful hurricane to hit the continental US in more than 50 years.
Though reduced to a tropical storm, it brought flash flooding to North Carolina and Virginia, soaking areas still recovering from Hurricane Florence.
Under a perfectly clear blue sky, families living along the Florida Panhandle emerged tentatively yesterday from darkened shelters and hotels to a perilous landscape of shattered homes and shopping centres, beeping security alarms, wailing sirens and hovering helicopters.
Governor Rick Scott said the Panhandle woke up to “unimaginable destruction”.
“So many lives have been changed forever, so many families have lost everything,” he said.
The full extent of Michael’s fury was only slowly becoming clear. Some of the hardest-hit areas were difficult to reach because of roads blocked by debris or water. An 80-mile stretch of Interstate 10 – the main east-west route along the Panhandle – was closed.
Some of the worst damage was in Mexico Beach where the hurricane crashed ashore on Wednesday as a category four monster with 155mph winds and a storm surge of 9 feet. Video from a drone revealed widespread devastation across the town of about 1,000 people.
Entire blocks of homes near the beach were obliterated, reduced to nothing but concrete slabs in the sand. Rows and rows of other homes were turned into piles of splintered lumber or were crumpled and slumped at odd angles. Entire roofs were torn away and dropped onto a road. Boats were tossed ashore like toys.
A National Guard team got into Mexico Beach and found 20 survivors overnight. The fate of many residents remained unknown last night. State officials said 285 people in Mexico Beach had refused to leave ahead of the hurricane despite a mandatory evacuation order.
As thousands of National Guard troops, law enforcement officers and medical teams fanned out, the governor pleaded with people in the devastated areas to stay away for now because of fallen trees, power lines and other debris.
“I know you just want to go home,” Mr Scott said. “You want to check on things and begin the recovery process, but we have to make sure things are safe.”
More than 900,000 homes and businesses in Florida, Alabama, Georgia and the Carolinas were without power.
The Coast Guard said it rescued at least 27 people before and after the hurricane came ashore, mostly from homes along the Florida coastline, and searched for more victims.
Among those brought to safety were nine people rescued by helicopter from a bathroom of their home in Panama City – another one of the hardest-hit spots – after their roof collapsed.
In Panama City, most homes were still standing, but no property was left undamaged. Downed power lines lay nearly everywhere. Roofs had been peeled off and carried away. Aluminium siding was shredded to ribbons. Homes were split open by fallen trees.
Hundreds of cars had broken windows. Twisted street signs lay on the ground, while pine trees were stripped and snapped off about 20ft high.
The hurricane also damaged hospitals and nursing homes in the Panama City area, with officials working to evacuate hundreds of patients. The damage at Bay Medical Sacred Heart included blown-out windows, a cracked exterior wall and a roof collapse.