Tropical Storm Ophelia regained hurricane strength and could threaten the southeast coast, forecasters said Friday.

At 11 p.m. Eastern time, Ophelia was centered about 255 miles east-northeast of Daytona Beach and about 240 miles south-southeast of Charleston, S.C.

Forecasters said Ophelia has been hard to predict. It could go out to sea, but it may also head anywhere from north Florida to North Carolina, said Robbie Berg, a meteorologist at the National Hurricane Center.

The Category 1 storm was moving northeast at about 7 mph and was expected to continue that track through Saturday. Maximum sustained winds were near 75 mph with higher gusts.

No significant change in strength was expected over the next day.

"The models that we look at, most of them are going in all different directions. So, it's making it difficult to forecast for us where Ophelia is going to go," Berg said.

In Flagler Beach, construction workers raced to fortify a section of State Route A1A after Ophelia pushed raging Atlantic waters up a 15-foot embankment Friday, undercutting the coastal highway. Ten-ton trucks hauled boulders to the damaged stretch of highway, which was closed in some sections.

Rebuilding will continue through the weekend, if necessary, said Florida Department of Transportation supervisor Ken Cato. "It all depends on Mother Nature," he said, nodding at the churning waves. "It depends on how violent she gets."

Ophelia, the season's seventh Atlantic hurricane, had weakened to a tropical storm and had been drifting away from Florida's northeast coast earlier Friday. But forecasters warned it could roar back toward the United States next week.

If it lands in Florida, it would be the seventh hurricane in the past 13 months to hit the state and the third this year.

Forecasters said residents of the Carolinas and northeast Florida should remain vigilant.

"It's really in the wheelhouse of Georgia and South Carolina with maybe landfall later on Tuesday," said Rich Thacker, the senior forecaster at the National Weather Service in Charleston.

Emergency officials in Columbia, S.C., said some of the state's workers helping with Katrina recovery could be called back if needed. "In a disaster, no state in the union has all the assets to do what will be needed," said Joe Farmer, a spokesman for the state's Emergency Management Division.

Along the Florida coast, residents and businesses anticipated the storm.

Near the A1A reconstruction, George Curovic, the general manager of Manny's restaurant, said it drew big crowds during last year's hurricane season because the restaurant was one of few in the Flagler Beach area with power.

But not this time, not after last year and not after what Hurricane Katrina did to Louisiana and Mississippi last week.

"Now they're getting away. I think they've seen too much damage, too much death," Curovic said. "All it takes is one tidal wave to wipe this place out."

Workers in Florida dump sand and rocks to fortify a sea wall along Route A1A in Flagler Beach against churning surf.