Arthur strengthened to a Category 2 hurricane Thursday night, its winds strengthening to 100 mph before it made landfall near the southern end of the Outer Banks.
Little change was expected in the storm's strength overnight into Friday, and Arthur was expected to weaken as it travels northward, slinging rain on Fourth of July festivities along the East Coast.
Forecasters expect Arthur to whip the Outer Banks — a 200-mile string of narrow barrier islands with about 57,000 permanent residents — with rain, heavy winds, storm surges and dangerous rip tides.
Warnings about the coming storm had prompted an exodus that began Wednesday night of thousands of vacationers and residents from the popular but flood-prone Outer Banks.
Forecasters are predicting the Category 2 hurricane will weaken on Friday night and become a post-tropical cyclone Saturday.
Prior to the storm, tourism officials had expected 250,000 people to travel to the Outer Banks for the holiday weekend. Gov. Pat McCrory warned people not to risk their safety by trying to salvage their picnics, barbecues and prepaid beach vacations.
"Don't put your stupid hat on," McCrory said.
Al Jazeera meteorologist Kevin Corriveau said the biggest issue will be flooding and storm surges in the areas Hurricane Arthur is expected to hit, including the northern part of South Carolina as well as North Carolina.
“We do expect to see later on this evening, probably about 2 a.m., the storm is expected to make landfall in Cape Hatteras. The biggest issue is the storm surge — we can expect to see 2 to 4 feet in that area,” he said.
The National Hurricane Center predicted Arthur would swipe the North Carolina coast early Friday with winds of up to 85 mph and travel north off the coast of New England later in the day, eventually making landfall in Canada's maritime provinces as a tropical storm.
Outer Banks residents and out-of-town visitors who fail to evacuate ahead of the hurricane's expected arrival should prepare for possibly getting stuck for several days without food, water or power, National Hurricane Center forecaster Stacy Stewart said Thursday.
"We want the public to take this system very seriously, go ahead and start their preparations because time is beginning to run out," he said.
Arthur, the first named storm of the Atlantic season, prompted a hurricane warning for much of the North Carolina coast. Tropical storm warnings were in effect for coastal areas in South Carolina and Virginia.
On the Outer Banks' Ocracoke Island, accessible only by ferry, a voluntary evacuation was underway. The evacuation for Hatteras Island residents and visitors began at 5 a.m. Officials called it mandatory, but some residents were likely to stay to try to ride out the hurricane, as in past storms.
Before sunset Wednesday on Route 12, a long line of cars, trailers and recreational vehicles formed a steady stream of traffic. The road has been sliced apart twice in recent years as storms cut temporary channels from the ocean to Pamlico Sound, and is easily blocked by sand and water.
Other areas of the Outer Banks were taking a cautious yet optimistic approach: No evacuations had been ordered for areas north of Hatteras, including the popular town of Kill Devil Hills, which was the site of the Wright brothers' first controlled, powered airplane flights in December 1903.
There, plenty of people enjoyed the beach Thursday, lounging on chairs or under umbrellas. A few dipped into the water, and a lifeguard stand was staffed.
The holiday weekend was not expected to be a complete loss on the Outer Banks. Forecasters said the storm would move through quickly with the worst of the weather near Cape Hatteras about dawn Friday. Then it was expected to clear.
Farther north, the annual Boston Pops Fourth of July concert and fireworks show was moved forward a day because of potential heavy rain ahead of Hurricane Arthur. Organizers and public safety officials said Thursday appeared to be the better of two potential bad weather days.
On Thursday morning, Arthur was about 300 miles southwest of Cape Hatteras and moving north around 9 mph with maximum sustained winds of 80 mph.
Al Jazeera and wire services