Debby pours more than a foot of rain on coastal Georgia, South Carolina

By Rich McKay and Tyler Clifford

ATLANTA (Reuters) -Tropical Storm Debby inundated coastal Georgia and South Carolina with a deluge of rain that could flood Charleston, Savannah and other cities on Tuesday, a day after it slammed into Florida's Gulf Coast as a hurricane.

At least six people have died in Florida and Georgia in the wake of the storm, which is expected to linger over the southeastern and mid-Atlantic coasts for days.

Between 10 inches (25 cm) and 20 inches (51 cm) of rain was expected to fall along parts of Georgia, South Carolina and North Carolina through Friday and cause catastrophic flooding, the National Hurricane Center said. The governors of those states have declared states of emergency.

The storm featured 45 mile-per-hour (72 km per hour) winds as it moved slowly just south of Savannah, Georgia, early on Tuesday morning. Heavy rainfall could cause flooding in parts of the mid-Atlantic through Sunday, the center said.

More than 8 inches (20 cm) of rain have already fallen on Savannah and Valdosta, Georgia, the National Weather Service said. Charleston and Hilton Head, South Carolina, have received between 10 and 12 inches (25 and 30 cm) of rain so far, the weather service said, with more on the way.

In Savannah, it was coming down hard outside the landmark Bellwether House, a 16-room bed-and-breakfast in the city's historic district, but general manager Victoria Hill was not too concerned.

"This place was built in 1876," she said. "It's built rock-solid, and you can imagine how many storms have hit over the last century."

Hill said a lot of tourists canceled their reservations because of the storm, but a handful of guests were staying on.

"We here, we're open and we're holding up. We'll all ride this out together."

Charleston Mayor William Cogswell said more than 2 feet (61 cm) of rain is expected in his city before the storm passes. Even at low tide, storm surges of between 4 and 6 feet (1.2 and 1.8 meters) will prevent floodwaters from draining into the sea, he said.

There are "not enough pumps in the world" to handle that much rain, Cogswell said late on Monday. He has since extended a citywide curfew until Wednesday morning.

"Nobody should be out on the streets in these conditions unless it is an absolute emergency," the mayor said.

About 50 miles (80 km) west of Charleston, fears of a breach at the McGrady Dam in Colleton County, part of the state's Lowcountry, prompted the county sheriff's office to warn residents to evacuate immediately on Tuesday morning.

Debby made landfall as a Category 1 hurricane in the Big Bend region of Florida's Gulf Coast on Monday morning, dumping 8 to 16 inches (20 to 41 cm) of rain in parts of central Florida, according to local reports. The storm has been blamed for five deaths in Florida and one near Valdosta, Georgia.

Nearly 110,000 customers were without power in Florida as of Tuesday morning, according to poweroutage.us, down from a peak of 350,000 on Monday. And more than 17,000 were without power in Georgia. Hundreds of flights to and from the state were canceled.

Weather conditions could spawn tornadoes as well, according to the National Hurricane Center. A suspected twister flipped over cars and damaged restaurants in Moncks Corner, South Carolina, about 30 miles (48 km) north of Charleston, early Tuesday morning. Mayor Thomas Hamilton Jr. said there were minor injuries.

The hurricane center said Debby would slow down and move east and off Georgia's shore on Tuesday before turning north and drifting inland over South Carolina near Charleston on Thursday.

Vice President Kamala Harris postponed a presidential campaign stop scheduled this week in Savannah, the Savannah Morning News reported.

Savannah Mayor Van Johnson said the city could expect a "once in a thousand year" rain event.

"This will literally create islands in the city," Johnson said.

Cedrick King, a businessman from coastal Brunswick, Georgia, said he and his family had packed up their belongings on Tuesday and were ready to make the five-hour drive to Atlanta.

"We're headed north, far away from this storm," he said.

(Reporting by Rich McKay in Atlanta and Tyler Clifford in New York City; Editing by Frank McGurty and Jonathan Oatis)