(Updates with hurricane making landfall, changes in movement and size, paragraphs 1-6)
By Chris Keane
NAGS HEAD, N.C., July 3 (Reuters) - The first hurricane of the Atlantic season made landfall on the North Carolina coast Thursday night, a windy, wet party-pooper that forced thousands of vacationers to scrap their July Fourth holiday plans amid evacuation orders.
Hurricane Arthur crossed the coast near Cape Lookout at the southern end of North Carolina's Outer Banks at 11:15 p.m. EDT (0315 GMT), with maximum sustained winds of 100 miles per hour (160 kph), earning it Category 2 status on the five-step Saffir-Simpson scale of hurricane intensity, according to the U.S. National Hurricane Center.
Moving northeast at 18 mph (30 kph), Arthur is the first hurricane to hit the United States since Superstorm Sandy devastated New York and New Jersey in October 2012 and caused $70 billion in estimated damage.
Despite growing in intensity on Thursday, Arthur remained a medium-sized storm, with hurricane force winds only extending outward up to 40 miles (65 km) from the center, although lesser tropical storm-force winds extended 150 miles (240 km).
After scything through the Outer Banks, Arthur is expected to move toward the northeast over cooler water on Friday, diminishing in strength and posing little risk to the northeastern United States, forecasters said.
Tropical storm warnings were issued on Thursday for Cape Cod and Nantucket, as well as parts of eastern Canada, including New Brunswick, Nova Scotia, and the islands of Cape Breton and Prince Edward.
The storm disrupted plans for holiday beachgoers and others ordered off North Carolina's low-lying barrier islands in its path. Tourists and some residents packed ferries and crowded the only highway off Ocracoke and Hatteras islands, where voluntary and mandatory evacuations were in effect.
Ferry service between some islands was suspended on Thursday afternoon as conditions began to deteriorate, with 22-foot waves reported offshore and heavy rain and wind gusts reported along the coast.
Some people on Hatteras Island planned to ride out the storm. Retiree Gerry Lebing said he was tying things down at his house and moving cars to higher ground.
Troy Scroggin drove from Virginia to check on his vacation home on Hatteras Island. "We had to batten down the hatches and we're going to stay and see what it's like," he said.
The storm could bring life-threatening rip currents and a storm surge of up to 5 feet (1.5 meters) to North Carolina's barrier islands, forecasters said.
HIGHWAY AT RISK FROM STORM SURGE
North Carolina officials warned the storm surge could make the narrow 50-mile (80 km) Highway 12 connecting Hatteras Island to the mainland impassable. The state was putting extra heavy equipment in place to remove sand and the overwash as soon as possible after the storm passes.
Part of the highway was washed out by storm surge for two months after Sandy, forcing people to use ferries to reach the mainland.
"I think it's probably going to get knocked out again," said Jeff Masters, a hurricane expert with private forecaster Weather Underground.
State officials said 105 National Guard members have been deployed to help with storm preparation and safety, and 400 state troopers are helping with the evacuation efforts.
"Right now our crews are in place and ready to deploy once conditions allow for recovery efforts to begin," North Carolina Secretary of Transportation Tony Tata said in a statement.
"We will work to open the roads and resume ferry operations as quickly as possible."
Several towns and villages on North Carolina's coast rescheduled Independence Day festivities and fireworks as the storm approached.
Farther north, the beach resort of Ocean City, Maryland, and more than a dozen communities in New Hampshire and Connecticut moved their July Fourth fireworks display to Saturday.
Despite losing strength on Friday, Arthur would likely bring heavy rain to Boston and strong winds over Cape Cod and Nantucket. It would still be near hurricane strength when it passes over Nova Scotia on Saturday, according to Masters.
(Additional reporting by Gene Cherry in Raleigh, David Adams in Miami, Ted Siefer in New Hampshire and Richard Weizel in Connecticut; Writing by Colleen Jenkins and David Adams; Editing by Doina Chiacu and Jim Loney)