Gov. Mark Sanford is calling for a voluntary evacuation of South Carolina's northern coast as Tropical Storm Hanna moves slowly toward the U.S.

The governor's office says Sanford will hold a news conference at noon Thursday to discuss the state's response to the approaching storm.

Earlier Thursday, the National Weather Service issued hurricane watches for much of South Carolina's coastline, meaning hurricane conditions are possible within 36 hours.

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The weather service says tropical storm force winds could reach the state's northern coast by Friday afternoon and tides could be up to four feet above normal. The worst of the weather should come early Saturday.

Coastal residents moved boats and booked inland hotel rooms while National Guard troops prepared to deploy along the Southeastern coast as Hanna plowed through the Atlantic on a shifting track toward the U.S.

The uncertain path of the storm, which may become a hurricane by the time it hits land sometime on Saturday, had emergency officials holding off ordering coastal residents to head inland Wednesday.

Still, high schools in South Carolina canceled football games and workers in Savannah, Ga., put storm shutters over the windows of the gold-domed City Hall.

"Hopefully the good Lord will bless us and this storm will skirt past but we are ready in whatever case happens," North Charleston Mayor Keith Summey said.

Hanna, responsible for 61 deaths in Haiti, was tentatively predicted to hit somewhere along the South Carolina and North Carolina coasts, and its winds were forecast to rake along more southern shorelines.

Officials as far north as Washington, D.C., urged people to prepare for the possibility of heavy winds and rain.

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Two More Major Hurricanes Predicted for September.

The warnings had residents such as John Farrell making preparations. Farrell, 49, of Isle of Palms, spent part of Wednesday helping a friend move his 80-foot-yacht from the Charleston City Marina to a drydock for the winter.

"With hurricane season, it's time to do it," said Farrell, noting that two other storms are brewing in the Atlantic.

Hanna comes as New Orleans residents start to return home after fleeing Hurricane Gustav, which did less damage than feared but still caused serious flooding and could leave some in Louisiana without electricity for up to a month.

But Hanna wasn't spawning such a mass exodus just yet.

Some coastal residents booked inland hotel rooms while others gave a collective shrug. Officials contemplated whether to order evacuations, make them voluntary or simply tell people to sit tight, a decision complicated by Hanna's unpredictability and the prospect of turning major highways into one-way evacuation routes for the roughly 1 million people who live between Savannah and Wilmington, N.C.

"The time window is OK," Joe Farmer, spokesman for the South Carolina Emergency Management Division, said Wednesday evening. "We're monitoring the storm and letting the storm drive what we do."

Farmer said there was plenty of time for an orderly evacuation. He said calls for coastal residents to evacuate could come around noon Thursday, starting with voluntary evacuations.

He said various agencies were ready to respond, including about 830 law officers, and that 2,500 National Guardsmen were standing by, along with 700 doctors, nurses, social workers and pharmacists, who were prepared to be dispatched if needed.

North Carolina Gov. Mike Easley activated his state's National Guard to help respond to the storm, with up to 270 troops expected to be in place by Friday. He said the storm could bring 10 inches of rain to the state and pleaded with residents to be prepared. Food and other emergency supplies are available at state emergency warehouses — examples of a state accustomed to responding to hurricanes.

"We have in place everything that we need," Easley said.

Cape Lookout National Seashore superintendent Russell Wilson ordered visitors to leave uninhabited islands at the park north of Wilmington, N.C., which were to close at 5 p.m. Thursday.

Rangers at the Cape Hatteras National Seashore were pulling out hurricane plans and emergency planners along the state's southern coast were preparing.

"It's going to put our county in hurricane force winds for a while, which we weren't anticipating initially," said Mark Goodman, emergency management director in Onslow County on North Carolina's central coast, home to Camp Lejeune.

While no evacuations were ordered Wednesday, Hanna already was disrupting other events.

The Marines at Parris Island, S.C., moved their weekly recruit graduation up a day to Thursday. South Carolina restricted port operations. In North Carolina, Air Force bases sent planes to Ohio.

Some said they were unimpressed by forecasts the storm could bring 80 mph winds as it neared land.

"I'm not evacuating. I don't have any concerns about it. We're going to stay," said Margarita Lynn, 58, as she walked her dogs along a road on Sullivans Island near Charleston.

Lynn said the media and people not accustomed to the storms were the ones causing all the ruckus. She said she simply went to the store and bought a new tarp in case her roof was damaged.

"We're not hysterical about things like this. We choose to live here," she said. "Every time there is a hurricane, people everywhere get hysterical about it."

And Hanna wasn't the only tropical weather system to watch. Farther out to sea, Hurricane Ike reached Category 4 strength as it spun westward across the Atlantic and could arrive in the Bahamas on Sunday. Tropical Storm Josephine was out there, too.

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