Forecasters said up to 5 inches (13 centimeters) of rain were possible in northern Alabama and central and north Georgia. A flood warning was also issued for Asheville, North Carolina.
Water flooded more than a dozen homes in St. Charles Parish, Louisiana, on Thursday.
A Trader Joe’s store in Metairie outside New Orleans lost power during the storm Thursday, prompting the chain to donate more than 10,000 pounds (4,500 kilograms) of perishable grocery items to the Second Harvest Food Bank.
Food bank spokesman Joe Vise said the refrigerated and frozen items will be distributed across 23 parishes in the state.
Teams were heading out in Mississippi on Friday to determine the extent of damage.
Three emergency shelters were set up in Forrest and Jones counties, but only a few people were in them early Friday, Flynn said.
The National Weather Service planned to check the Vicksburg area on Friday for evidence of a tornado, said forecaster Mike Edmunston in Jackson.
There had been at least two dozen water rescues in the Hattiesburg area, Edmunston said.