This projected storm track shows Tropical Storm Arthur slamming into the Outer Banks with the potential of hurricane-force winds early Friday/NOAA.

Editor's note: This updates with a mandatory evacuation order issued for Hatteras Island at North Carolina's Outer Banks.

The approach of Tropical Storm Arthur, which was building towards hurricane strength Wednesday evening, prompted North Carolina officials to issue a mandatory evacuation order of Hatteras Island on the Outer Banks, much of which is occupied by Cape Hatteras National Seashore.

The order, from Dare County's Emergency Management office, said residents and visitors on Hatteras Island would have to begin leaving the island at 5 a.m. Thursday, and that no access would be allowed onto the island after 5 a.m. Thursday.

All Hatteras Island residents and visitors are advised to evacuate as expediently as possible during daylight hours on Thursday before the effects of Tropical Storm Arthur begin to bring high winds, rough seas, dangerous rip currents, and the potential for water and sand overwash on NC Highway 12....Visitors should evacuate with all personal belongings and follow instructions offered by their property management company.

The prospect of Tropical Storm Arthur slamming into the Outer Banks prompted the National Park Service earlier Wednesday to close Cape Hatteras National Seashore, Cape Lookout National Seashore, Fort Raleigh National Historic Site, and Wright Brothers National Memorial.

Park Service officials said that on its current track, the tropical storm could generate storm conditions beginning Thursday and possibly continuing through Saturday. The National Hurricane Center early Wednesady issued a hurricane watch for the Outer Banks, with the potential of hurricane-force winds above 74 mph hitting there Friday, though later Wednesday it upgraded it to a warning for some areas of the Outer Banks. If the storm's arrival at the Outer Banks coincides with the high tide, the storm surge could approach 4 feet, the National Weather Service forecast.

At Cape Hatteras National seashore, "all NPS campgrounds -- Ocracoke, Frisco, Cape Point and Oregon Inlet -- will close at noon today, Wednesday and remain closed until further notice," national seashore officials announced Wednesday morning. "The Ocracoke campground reservation system has been temporarily suspended. Silver Lake Marina NPS docks will close at noon Wednesday. Ocracoke and Hatteras Island NPS Visitor Centers will close at noon on Wednesday, and then remain closed until further notice.

"Bodie Island Visitor Center, Wright Brothers National Memorial, and Fort Raleigh National Historic Site will be closed Thursday and Friday, July 3 and 4," the release added.

All previously scheduled evening programs were canceled, as well. Lifeguard beach operations at Ocracoke, Buxton, and Coquina were to close at noon on Wednesday until further notice. The Cape Hatteras Lighthouse was to close at noon Wednesday and remain closed until further notice. The Bodie Island Lighthouse was to close at 6:30 p.m. on Wednesday, and the climbing reservation system was to be suspended beginning Thursday.

All national seashore beaches would be be closed to off-road vehicles by 9 p.m. on Wednesday, and remain closed until further notice. The Buxton and Ocracoke Off-Road Vehicle Permit offices were to close at noon on Wednesday, while the Bodie Island Off-Road Vehicle Permit office would close at 4:30 p.m. on Wednesday.

To the south of Cape Hatteras, officials at Cape Lookout National Seashore said they would shut their operations down by 5 p.m. Wednesday.

"On Friday, July 4, the storm will be closing in on the Outer Banks of North Carolina. At this juncture, the storm is anticipated to be Hurricane Arthur, with winds to 75 mph," a statement from Cape Lookout read. "The National Park Service has ordered ferry operations to evacuate visitors and vehicles by 5 p.m. Wednesday, July 2. Again, the park will be closed beginning Wednesday at 5p.m. Park facilities including the Visitor Centers in Beaufort and Harkers Island will be closed on Wednesday at 5 p.m. and until further notice."

Visitors to the national seashores and area residents were urged to listen to NOAA weather radio and local radio and media for updates and advisories.