Hurricane Earl raked North Carolina's barrier islands with gusting winds, pounding surf and rain on Thursday as it took a swipe at the U.S. East Coast on an offshore path towards New England and Canada.

After weakening from a Category 4 peak to a downscaled but still dangerous Category 2 storm, Earl was running northeast parallel to the U.S. eastern seaboard, a track that appeared to spare the coast so far from the worst of its violent weather.

At 11 p.m. EDT (4:00 a.m. British time), Earl was packing top sustained winds of 105 miles per hour (165 kph) and its centre was passing east of North Carolina's Outer Banks islands that jut into the Atlantic, the U.S. National Hurricane Centre said.

It positioned Earl's core at about 115 miles (185 km) south southeast of Cape Hatteras, and about 570 miles (915 km) south southwest of Nantucket, Massachusetts.

Tropical storm-force winds are occurring along the North Carolina coast within the warning area and hurricane conditions are expected in the Outer Banks overnight, the Miami-based centre said.

A slight further weakening was forecast during the next 24 to 36 hours but Earl was expected to remain a large hurricane as it passed near the Outer Banks and headed for southeastern New England, which it would approach on Friday night.

Outer Banks residents who had ignored mandatory evacuation orders said they were experiencing gusting winds and rain.

It's definitely picking up, both the wind and the rain. We're getting more wind and the rain is starting to come down harder, said Mike Howe, who lives in the village of Salvo.

A marine weather buoy off Cape Hatteras was registering 20-foot (6.1-metre) waves.

Emergency officials said there were no immediate reports of any damage.

U.S. EAST COAST ON ALERT

As oil refineries, drilling platforms and nuclear power plants along the Atlantic coast monitored Earl's path, EnCana Corp said it suspended drilling and pulled personnel from a Nova Scotia rig in Canada.

Exxon Mobil said it had pulled nonessential staff from its Sable field in offshore Nova Scotia.

The U.S. Energy Information Administration said about 1.1 million barrels per day (bpd) of oil refining capacity lies in the likely U.S. affected area.

At least 100,000 people were ordered to evacuate from North Carolina's Outer Banks islands as Earl approached the Atlantic shore. It was one of the biggest storms to menace the state since Hurricane Floyd killed more than 50 people in 1999.

The U.S. Census Bureau estimated 26 million people in coastal counties from North Carolina to Maine could feel Earl's effects in the next two days.

While a direct U.S. landfall was not forecast, Earl was still expected to sideswipe the North Carolina coastline and farther northward before the Labour Day holiday weekend marking the end of the summer vacation season.

Forecasters warned that hurricane-force winds from Earl still extended out 70 miles (110 km) from its centre, so it would not need a direct landfall to inflict damage from strong wind and high seas.

On Ocracoke Island, charter boat captain Ryan O'Neal, 31, said he was staying put with his dog despite an evacuation order. He spoke as the last ferry off the island, accessible only by boat, left on Thursday morning.

I've been here for every hurricane since I was born. This one may be bad, but I'm sure we've had worse. I've got to watch out for my house and boat, O'Neal said.

Watches and warnings were posted along the Atlantic coast for North Carolina, Virginia, Maryland, Delaware, New Jersey, New York, Connecticut, Rhode Island, Massachusetts, Maine and parts of Canada's Nova Scotia and New Brunswick provinces, alerting residents hurricane and tropical storm conditions were possible in the next day or so.

Nantucket, (Martha's) Vineyard and the eastern half of the Cape (Cod) will experience hurricane-force winds, National Hurricane Centre Director Bill Read said earlier on Thursday.

Few vacationers were visible along Main Street in Hyannis, normally one of the busiest towns in the beach community of Cape Cod, which is expected to feel the storm on Friday.

We were tempted to leave, but I think we'll stick it out, said John Tracy, 58, of Newport, New York, who was in town to visit his daughter.

DON'T WAIT

Federal Emergency Management Agency Administrator Craig Fugate urged coastal residents to stay alert and heed evacuation orders.

People need to be rapidly completing their preparedness now, Fugate said. Don't wait for the forecast every six hours and think it's going to get better.

Massachusetts Governor Deval Patrick declared a state of emergency, an administrative step that speeds storm relief.

Cars lined up to get off the island resort of Nantucket off Cape Cod and hundreds of boats were removed from its main harbour. Smaller ferry line back-ups were seen on Martha's Vineyard, the island that recently hosted the Obama family's summer vacation and is home to many celebrities.

No storm has threatened such a broad swath of the U.S. shoreline -- the densely populated coast from North Carolina to New England -- since Hurricane Bob in 1991.

Behind Earl, Tropical Storm Gaston dissipated in the central Atlantic. There was still a chance it could regenerate as it moved west towards the Caribbean Sea, but it was too early to tell whether it would enter the energy-rich Gulf of Mexico.

(Additional reporting by Tom Brown, Kevin Gray and Jane Sutton in Miami, Joe Silha in New York, Ros Krasny in Boston and Scott Malone in Hyannis; writing by Jane Sutton and Pascal Fletcher; editing by Anthony Boadle)

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