A hurricane watch was posted Saturday for the Southeast coast as Ophelia strengthened into a hurricane once again and meteorologists said its meandering course could take a sharp turn toward land.

A hurricane watch was posted along a 300-mile stretch from the Georgia-South Carolina line to North Carolina's Cape Lookout (search), meaning hurricane-force wind of at least 74 mph was possible by Sunday evening, the National Hurricane Center (search) said.

North Carolina's governor declared a state of emergency as the storm's track shifted northward with a forecast landfall on the North Carolina coast next week.

The storm wasn't close enough to North Carolina that a decision had to be made on whether to order evacuations, said Eddie King, Pender County emergency management director.

South Carolina officials said a decision would be made soon about whether to order evacuations, but Charleston County (search) announced it would open shelters Saturday evening for voluntary evacuees from low-lying areas and barrier islands.

"We don't think it's a done deal yet," said Joe Farmer, a spokesman for the South Carolina Emergency Management Division. "It's moving really slow so we have to hang with it. But there is some expectation it will move toward the coast."

The crew of an Air Force hurricane hunter airplane flying through Ophelia measured top sustained wind of 80 mph. It could strengthen a bit before an expected Tuesday landfall, said Eric Blake, a meteorologist at the hurricane center in Miami.

"Almost every (computer) model indicates a United States landfall," he said. "It's time to make those preparations."

At 8 p.m. EDT Saturday, Ophelia was about 200 miles southeast of Wilmington, N.C., and was drifting toward the northeast, but forecasters predicted little movement for the rest of the weekend.

Several shelters that opened Saturday already had been closed, and two that remained open didn't have any residents, said Red Cross Carolina Lowcountry Chapter executive director Jim Ledbetter.

Ophelia already was contributing to rough surf along the coast.

"There are large swells from Ophelia and residual swells from (Tropical Storm) Nate and from the northeast winds we've had over the past few days. You can imagine how confused the seas are," said meteorologist Steve Pfaff at the National Weather Service in Wilmington, N.C. He said a buoy at Frying Pan Shoals, 35 miles off Cape Fear, was reporting 12-foot waves.

Nate and another tropical storm, Maria, posed no threat to land as they weakened over the cooler water of the north Atlantic.

If Ophelia makes landfall in South Carolina it would the third hurricane in 13 months to strike the state. Hurricanes Charley and Gaston hit the South Carolina coast last season in the same general area.

Ophelia is the seventh hurricane in this year's busy Atlantic hurricane season, which began June 1 and ends Nov. 30. Peak storm activity typically occurs from the end of August through mid-September.