Hurricane Dorian sideswiped the US Carolinas with shrieking winds, tornadoes and sideways rain on Thursday as it closed in for a possible direct hit on the dangerously exposed Outer Banks islands.
At least four deaths in the Southeast were blamed on the storm.
Twisters spun off by Dorian peeled away roofs and flipped trailers, and more than 250,000 homes and businesses were left without power as the hurricane pushed north along the coastline, its winds weakening after sunset to 100 mph (160 kph).
Trees and power lines littered flooded streets in Charleston's historic downtown.
Gusts had topped 80 mph (129 kph) in some areas.
North Carolina's Outer Banks, a thin line of islands that stick out from the US coast like a boxer's chin, braced for a hit late on Thursday or early on Friday.
To the north, Virginia was also in harm's way, and a round of evacuations was ordered there.
The damage from the same storm that mauled the Bahamas was mercifully light in many parts of South Carolina and Georgia as well, and by mid-afternoon many of the 1.5 million people who had been told to evacuate in three states were allowed to return.
But overnight winds will cause trees and branches to fall on power lines, and debris could block repair crews from accessing damaged lines, said Mike Burnette senior vice president of Electric Cooperatives, a North Carolina utility provider.
Customers should prepare for prolonged power outages, he said.
"We have a long night ahead of us. Everyone needs to stay in a safe place and off the roads until the storm passes," North Carolina Governor Roy Cooper said.
After leaving at least 30 people dead when it slammed the Bahamas with 185 mph (295 kph) winds, Dorian swept past Florida at a relatively safe distance, grazed Georgia, and then hugged the South Carolina-North Carolina coastline.