In Florida, pictures and video from Mexico Beach - a community of about 1,000 people where Michael made landfall around midday Wednesday - showed scenes of devastation, with houses floating in flooded streets, some ripped from their foundations and missing roofs.
US Army personnel used heavy equipment to push a path through debris in Mexico Beach to allow rescuers through to search for trapped residents, survivors or casualties, as Blackhawk helicopters circled overhead.
"It's hard to convey in words the scale of the catastrophe in Panama City".
More than 900,000 homes and businesses are still without power in Florida, Alabama, Georgia and the Carolinas.
FEMA's Long said he's anxious the number of deaths will rise Thursday.
After daylight Thursday residents of north Florida would just be beginning to take stock of the enormity of the disaster.
Florida state emergency officials say they've done an initial search of 80 percent of the area affected by Hurricane Michael, and found no sign of widespread deaths.
Authorities said a falling tree killed a man outside Tallahassee, Florida, and an 11-year-old girl in Georgia was killed when the winds picked up a carport and dropped it on her home.
"This is what we expect with storm surge and high wind events", said Craig Fugate, former director of the Federal Emergency Management Agency and a former emergency management chief for the state of Florida.
He spoke with CNN's Brooke Baldwin live on air Thursday, in front of a home that was pushed onto its side.
On Thursday, authorities and residents will begin to discover the full extent of Michael's destruction in Florida and Georgia while the Carolinas brace for possible flooding, tornadoes and risky winds in numerous same areas still recovering from Hurricane Florence flooding.
The eye of the storm was 30 miles west of Augusta, Ga., as of the NHC's 5 a.m. EDT update.
11-year-old Sarah Radney, identified by a coroner Thursday, was killed when a portable carport fell on her home in Seminole County, which is in the extreme southwest corner of Georgia.
An additional 16 roads have been closed, in addition to those closed by Hurricane Florence, due to downed trees and standing water, he said. "If the house and the cars are destroyed they can be replaced, but my niece needs her dad - and as much as I sometimes can't stand him, I would do anything to just know he's OK", McCall said.
Michael, which has since been downgraded to a tropical storm, battered the Florida Gulf Coast before moving on to Georgia and the Carolinas. More than 375,000 people up and down the Gulf Coast were ordered or urged to clear out as Michael closed in. I can't think of anything that is more related to hell than that, ' he said.
Tropical Storm Michael is racing across the Carolinas.
Tropical storm conditions are occurring over portions of central and eastern SC and will spread northward over central and eastern North Carolina this afternoon and evening.
Home after home was razed from its foundations in the town of around 1,000 people. And then there was the life-threatening storm surge.