US forecasters have warned of life-threatening flash flooding in parts of the deep south, particularly across central Alabama, as Tropical Depression Claudette travels over coastal states.
Heavy rain led to high water late on Saturday into early Sunday in the Birmingham and Tuscaloosa metropolitan areas.
More than 20 people were rescued by boat due to flooding in Northport, Alabama, WVUA-TV reported.
Birmingham Fire and Rescue Service Captain Bryan Harrell told news outlets that a search was under way for a man who was possibly swept away by flooding.
The rapidly changing conditions came as Claudette was beginning to batter parts of Georgia and the Carolinas early on Sunday.
The system was about 75 kilometres south of Birmingham, with sustained winds of 45km/h.
It was moving northeast at 20km/h, the National Hurricane Center said.
Claudette was declared a tropical storm early on Saturday morning, well after the storm's centre had gone ashore southwest of New Orleans.
Shortly after landfall, a suspected tornado spurred by the storm demolished or badly damaged at least 50 homes in a small town in Alabama, just north of the Florida border.
In north Florida, winds - in some cases reaching 137km/h - caused an 18-wheeler to flip on its side.
The storm also dumped flooding rains north of Lake Pontchartrain in Louisiana and along the Mississippi coast, inundating streets and, in some areas, pushing water into homes.
Later, the storm was drenching the Florida Panhandle and, well inland, a broad expanse of Alabama.
Claudette is forecast to cross into the Atlantic Ocean on Monday and eventually regain tropical storm strength.
Australian Associated Press
