A vehicle lies upside down in a ditch following a suspected tornado, Saturday, April 13, 2019 in Franklin, Texas. On Saturday morning, the storm system dropped hail ranging from the size of golf balls to baseballs on San Antonio.
The most significant risk of severe weather is expected Saturday, but there's still considerable potential Sunday.
The biggest threat with the storms will be damaging winds with the possibility of a tornado.
Damage was reported early Saturday evening in Vicksburg, Mississippi, as severe thunderstorms rumbled through the city.
Residents have reported downed power lines, cars overturned and homes completely destroyed, KBTX reports.
"We'll be seeing severe weather from Florida to NY, with the most unstable parts so far in Georgia", said meteorologist David Roth of the National Weather Service Weather Prediction Center.
He said the threat for severe weather is greatest at such times but that the risk remained even after warm temperatures dropped. The system shifts to the Ohio Valley and the Southeast on Sunday.
To the north, dime-sized hail pounded the Dallas-Fort Worth area. The death is believed to be storm related, the sheriff's office said.
The Mississippi Emergency Management Agency warned of a confirmed tornado around Saturday night.
CNN meteorologist Chad Myers said the warm air present during Saturday afternoon enhanced the atmosphere's instability, creating more energy for storms to tap into and aiding in their development.
A possible tornado knocked out power and left damage in Troy, about 50 miles (80 kilometres) south of Montgomery.
"It looks like a storm came up through Louisiana and into MS and exploded in Monroe County", Monroe County Sheriff Cecil Cantrell said. We have a lot of flooding.
At Georgia's Augusta National Golf Club, organizers of The Masters golf tournament moved up tee times Sunday to try to beat risky weather.
We have an Alert Day due to strong storms later this afternoon and tonight. The main time frame is from approximately 4 p.m. until 2 a.m.; earlier time west of I-55, then later farther east as storms moves across the state. Very heavy rain - capable of producing pockets of flash flooding, damaging wind gusts, hail, and even an isolated, short-lived tornado can not be ruled out.