The storm marched from Louisiana to Georgia on Thursday, killing one person in Mississippi, where a twister was spotted.
A tornado also was reported in southeastern Tennessee, prompting authorities to declare a state of emergency. While tornado watches for the Atlanta area had been lifted by early Friday, they remained in effect for parts of the Carolinas throughout the day.
In Georgia, the world's best golfers were keeping a wary eye on the storms as they prepared to play in the second day of the Masters at Augusta National.
The weather was warm and sunny on the first day of the four-day tournament, but severe storms were forecast overnight, and golf- and baseball-sized hail were reported in northeast Georgia and western parts of the Carolinas.
As the system moved through the Southeast, high winds knocked over trees and power lines in rural west Alabama and eastern Mississippi. About 50 school systems in central and north Alabama sent students home early, and a few government offices and businesses also closed early.
In Mississippi, Emergency Management Agency spokesman Greg Flynn said Thursday that one person died and several people were injured after a reported tornado struck Kemper County in the far-eastern part of the state.
At Contract Fabricators Inc. in Kemper County, bent pieces of tin hung from the heavily-damaged building. A tractor-trailer was twisted and overturned, and debris from the business was strewn through the woods across the street.
Tabatha Lott, a dispatcher in Mississippi's Noxubee County, said there were numerous injuries reported in the town of Shuqualak, as well as reports of damaged buildings and power outages.
Derek Cody, an amateur storm chaser who works at East Mississippi Community College in Scooba, just south of Shuqualak, told The Associated Press he drove north to the small town to try to catch a glimpse of a tornado there.
He said he got out of his car on U.S. 45 just as the twister was approaching the highway, only to be hit by a strong gust of wind moving into the storm that almost knocked him over.
"I kind of sat there and hoped it would cross right in front of me," Cody said. "It was just a black mass that moved across the road."
Cody said the centre of Shuqualak, an eastern Mississippi town of 500 people, was unaffected. But he said a gas station and about 10 or so houses west of the town centre were damaged and that one house was "completely flattened" with debris blown across the road.
Shuqualak resident Kathy Coleman, 57, said she was outside her home, signing for a delivery of her dialysis medication, when the deliveryman hustled her back into the house. They huddled with Coleman's housekeeper in the bathroom when the storm hit.
"All I could hear was trees breaking and falling and glass," Coleman said. "He started praying and I started praying. Thank God he was here."
The T-shaped system first swept across the nation's midsection Wednesday night and pummeled portions of Missouri.
An EF-2 tornado, which generally carries winds that can exceed 252 km/hour, appears to have damaged dozens of homes in the St. Louis suburb of Hazelwood. More than 23,000 homes and businesses lost power, the National Weather Service said Thursday.