Suspected tornadoes were reported in Louisiana, Mississippi, Alabama and South Carolina, and thousands of people were without power as trees and power lines were downed.
In South Carolina, three people were killed and five injured when an apparent tornado swept through a rural community near Rock Hill, about 20 miles south of Charlotte, N.C. In north Georgia, an unidentified person was killed when a tree fell on a sport utility vehicle.
In eastern Alabama, a suspected twister splintered trees and demolished mobile homes at a pair of housing parks near the Auburn University campus. Less than seven months ago, a massive tornado roared past the campus of archrival University of Alabama in the western part of the state.
It was the worst bout of weather for the state since about 250 people were killed during the tornado outbreak in April. Both campuses were spared major damage this time.
As weather service experts fanned out to assess damage, Auburn graduate student Staci DeGeer didn't have any doubts about what sent a pair of trees crashing through her mobile home at Ridgewood Village.
"It's tornado damage. I'm from Kansas; I know tornado damage," said DeGeer, who wasn't home at the time. "It's kind of hit or miss. There will be two or three (trailers) that are bad and then a few that are OK."
A similar scene occurred in southeastern Mississippi, where Jones County emergency director Don McKinnon said some people were briefly trapped in their homes as trees fell on them. Mobile homes were tossed off their foundations. In all, 15 people were hurt in the area.
As the weather moved east, tornado warnings and watches were issued in Georgia and South Carolina.
Forecasters said a cold front stretching from the Gulf of Mexico to the Northeast was to blame. Temperatures dropped in some areas from the low 70s to the 50s as the front passed, and winds gusted to near 30 mph.
Damage was reported in several parts of Alabama. In Sumter County, in the west-central part of the state, an elderly woman was in her home as a tree crashed into it. She had to be taken to the hospital.
In Tuscaloosa, home of the University of Alabama, the day was a harsh reminder of the threat of violent weather for communities still recovering from the killer tornadoes.
"It makes you sit up on the edge of the chair a little more," said Tom Perryman, who works for the school system in Tuscaloosa County, which was hard hit in April.
Some 130 miles to the east, the ailing oaks at Toomer's Corner on the Auburn campus, were OK. An Alabama fan is suspected of poisoning the famous trees in February.
Nearby, DeGeer's dog Jack rode out the storm in her mobile home without injury, but the trailer itself didn't fare as well.
"It looks like I redecorated with a wilderness theme. There are trees through my house," she said.
In southern Louisiana, a suspected tornado hit a neighborhood in Houma, splintering a home. Crews helped clean up storm debris near a school and the Red Cross sent workers to help with damage assessments.
Johnson reported from Birmingham and Associated Press writer Jay Reeves contributed to this report from there.