ATLANTA (AP) — South Georgians were bracing for heavy rains that could lead to flooding as Tropical Storm Andrea gained strength during its approach to the state.

Parts of southeast Georgia -- including Brunswick, Savannah, Valdosta and Waycross -- were under a tropical storm warning Thursday morning. The storm was expected to track northeast over the area through Thursday night.

Forecasters at the National Weather Service said heavy rains and flooding will be the main threats in Georgia, but isolated tornadoes are also possible.

"It looks like it's picking up speed and that's a good thing because it won't sit and rain us so long," said Jan Chamberlain, whose family runs the Blue Heron Inn Bed & Breakfast near the Sapelo Island Ferry station on Georgia's coast.

The ferry takes visitors to the barrier island, which is home to a few dozen full-time residents. The island is sometimes evacuated during hurricanes, but Chamberlain doesn't expect that to happen during this storm.

"The island residents are used to this kind of thing," she said Thursday morning. "So they know what to do and what to be prepared for."

In McIntosh County, also on the Georgia coast, emergency management director Ray Parker said he was concerned that Andrea's high winds could topple trees.

"Our main concern right now is the ground is already saturated from rains the past week," Parker said. "Around here, our root system doesn't go down that deep, so it doesn't take a whole lot to bring trees down."

Meanwhile, a flash flood watch was expanded early Thursday to include all of southwest and south central Georgia and part of northeast Georgia. That area includes Albany, Macon, Dublin, Vidalia, Statesboro and Augusta.

Forecasters said isolated areas in Florida and southeastern Georgia could get 8 inches of rain.