- Video report by ITV News Washington Correspondent Robert Moore
Search and rescue teams are searching for both bodies and survivors after the most powerful hurricane to hit the continental US in more than 50 years obliterated beachfront communities and killed at least 13 people.
Authorities expect the death toll to rise as rescue teams reach isolated areas.
Hurricane Michael’s pounding waves and winds slammed ashore on the Florida Panhandle as a Category 4 storm on Wednesday and, despite being downgraded to a tropical storm, was still spreading high winds, rains and flash flooding misery as far away as Virginia early on Friday.
Recovery is just beginning from the catastrophic destruction, which will take billions of dollars to repair.
In Mexico Beach, one of the worst hit areas, roofs have been lifted from buildings and pine trees snapped by 155mph winds.
In one Florida community, Panama City, most homes were still standing but none escaped unscathed.
Aluminium siding was shredded and homes were split by fallen trees.
Hundreds of cars had broken windows and downed power lines and twisted street signs lay everywhere.
As the clean up and repairs began, residents struggled to come to terms with what happened and face up to the uncertainties which lay ahead.
"I didn't recognise nothing. Everything's gone. I didn't even know our road was our road," said Tiffany Marie Plushnik, 25, an evacuee who returned to find her home in Sandy Creek too damaged to live in.
When she went back to the hotel where she took shelter from the storm, she found out she could no longer stay there either because of mould.
"We've got to figure something out. We're starting from scratch, all of us," Ms Plushnik said.
The hurricane also damaged hospitals and nursing homes in Panama City and officials worked to evacuate hundreds of patients.
“So many lives have been changed forever. So many families have lost everything" said Florida governor Rick Scott, calling it “unimaginable destruction".
After wreaking destruction in Flordia, Hurricane Michael headed north into neighbouring Georgia.
Across the ravaged region, officials have set up distribution centres to hand out food and water to victims.
Some supplies were brought in by trucks, while others had to be delivered by helicopter because roads had yet to be cleared of debris.
President Donald Trump announced plans to visit Florida and hard-hit Georgia early next week but did not say what day he would arrive.
"We are with you!" he tweeted.
Among the dead was an 11-year-old girl who died in Georgia when debris was hurled through a roof, hitting her in the head.
A man outside Tallahassee, Florida, was killed by a falling tree and a driver in North Carolina also was killed when a tree fell on his car.
Across Florida, Alabama, Georgia and the Carolinas, more than 900,000 homes and businesses were left without power by Michael.
Linda Marquardt rode out the hurricane with her husband at their home in Mexico Beach, a town which was almost completely destroyed by Michael.
Ms Marquardt's house filled with surging ocean water during the hurricane and is now full of mud.
“All of my furniture was floating,” said Ms Marquardt, 67.
“A river just started coming down the road. It was awful, and now there’s just nothing left.”
State officials said that by one count, 285 people in Mexico Beach defied mandatory evacuation orders and stayed behind.
Emergency officials said they have received thousands of calls asking about missing people.
But with mobile phone service out across vast swathes of the Florida Panhandle, officials said it was possible that some of those unaccounted for are safe and just have not been able to contact friends or family to let them know.
Governor Rick Scott said state officials still "do not know enough" about the fate of those who stayed behind in the region.
"We are not completely done. We are still getting down there," the governor added.
Shell-shocked survivors who barely escaped with their lives told of terrifying winds, surging floodwaters and homes cracking like eggs.
Federal Emergency Management Agency chief Brock Long said he expected to see the death toll rise.
"We still haven't gotten into the hardest-hit areas," he said, adding with frustration: "Very few people live to tell what it's like to experience storm surge, and unfortunately in this country we seem to not learn the lesson."
Long expressed worry that people have suffered "hurricane amnesia".
"When state and local officials tell you to get out, dang it, do it. Get out," he said.
On the Panhandle, Tyndall Air Force Base "took a beating," so much so that Colonel Brian Laidlaw told the 3,600 men and women stationed on the base not to come back.
Many of the 600 families who live there had followed orders to pack what they could in a single suitcase as they were evacuated ahead of the storm.
The hurricane's eyewall passed directly overhead, severely damaging nearly every building and leaving many a complete loss.
The primary school, the flight line, the marina and the runways were devastated.
"I will not recall you and your families until we can guarantee your safety. At this time I can't tell you how long that will take, but I'm on it," Laidlaw wrote.
"We need to restore basic utilities, clear our roads of trees and power lines, and assess the structural integrity of our buildings."
Meanwhile, in North Carolina’s mountains, motorists had to be rescued from cars trapped by high water.
More than 375,000 people up and down the Gulf Coast were ordered or urged to clear out as Michael closed in, but emergency authorities lamented that many ignored the warnings.
The Coast Guard said it rescued at least 27 people before and after the hurricane’s landfall, mostly from coastal homes.
Nine people had to be rescued by helicopter from a bathroom of a home in hard-hit Panama City after their roof collapsed.
As the clean-up continues, arguments are now underway as to whether the brutal storm was the result of climate change.