Debby makes second landfall in South Carolina as it marches northward

By Rich McKay and Brad Brooks

ATLANTA (Reuters) -Tropical Storm Debby made a second landfall northeast of Charleston early on Thursday as it dumped more rain on coastal South and North Carolina, exacerbating fears of flash flooding in areas already soaked by the slow-moving weather system.

The storm came ashore again near Bulls Bay, South Carolina, three days after slamming into Florida's Gulf Coast as a Category 1 hurricane on Monday, then traveling across northern Florida and Georgia to the Atlantic Coast.

Debby, which has killed at least six people, was located about 90 miles (145 km) north of Charleston and 65 miles (100 km) southwest of Myrtle Beach, South Carolina, on Thursday morning.

It could bring another 3 inches (7 cm) of rain on Thursday to parts of eastern South Carolina, the National Hurricane Center said, with total amounts in some spots exceeding 25 inches (64 cm) since Monday. Rainfall totals could reach 15 inches (38 cm) in southeastern North Carolina and 10 inches (25 cm) in parts of Virginia.

While Debby produced less rain on Wednesday than the previous days, it could pick up again on Thursday, said Rich Bann, a meteorologist with the National Weather Service.

"Moisture has pulsed back into Debby," Bann said, as it spent the last day parked over the Atlantic Ocean. "As Debby makes its way inland ... the threat of heavy rains will lead to flooding concerns."

Moving northwest at 7 miles per hour (11 km per hour) with maximum sustained winds of 45 mph (72 kph), Debby is likely to weaken into a tropical depression on Thursday afternoon or evening as its rains spread northward.

In the coming days, it will soak through Maryland, Washington, upstate New York and Vermont, although rainfall totals will moderate.

More than 140,000 customers were without power in the Carolinas on Thursday morning, according to the tracking site, Poweroutage.us. About 7,000 remained without power in Florida, down from a peak of 350,000.

An apparent tornado tore through eastern North Carolina and damaged at least four houses, a church and a school in Wilson County, North Carolina, early on Thursday morning, NBC affiliate WITN reported. The system could spawn tornadoes in the region on Thursday, the hurricane center said.

By the weekend, Debby could produce up to 6 inches (15 cm) of rain from Maryland into northern Vermont. But New York City will avoid the worst of the storm, said Josh Weiss, a forecaster with the weather service.

In Bulloch County, Georgia, about 50 miles (80 km) northwest of Savannah, four dams burst on Wednesday as a result of floodwaters, and officials warned the Cypress Lake Dam was at risk of failure on Thursday morning.

That forced the evacuation of local residents after homes were flooded and roads made impassable as lakes and creeks overflowed, the Bulloch County Sheriff's Office reported.

Emergency management officials were keeping a close watch as rainwater drained into the numerous river systems in the Carolinas over the coming days, presenting the risk of major flooding long after the storm exited.

(Reporting by Rich McKay in Atlanta and Brad Brooks in Colorado; additional reporting by Swati Verma; editing by Miral Fahmy, Bernadette Baum and Jonathan Oatis)