Earl becomes major hurricane, could swipe U.S. east

MIAMI (Reuters) - Hurricane Earl turned into a major Category 3 storm on Monday as it lashed northeast Caribbean islands on a track that could see it swiping the U.S. East Coast in the next few days, the U.S. National Hurricane Center said.

But the Miami-based center said it was too early to say what part of the U.S. eastern seaboard might take a direct impact from Earl, the second major hurricane of the 2010 Atlantic season.

Earl had sustained winds of 120 mph and additional strengthening was expected in the next 48 hours, the center said.

The hurricane was moving west-northwest on a curving track that the National Hurricane Center said would take it east of Cape Hatteras, North Carolina, in the next few days.

Hurricane center forecaster Jessica Schauer said authorities along the U.S. eastern seaboard should closely monitor Earl's progress. "Right now it's forecast to pass off the coast of Cape Hatteras, probably within about 300 miles but that forecast track can change," she told Reuters.

Schauer said a direct hit to the North Carolina coast could not be ruled out.

On its current path, Earl posed no threat to the Gulf of Mexico, where major U.S. oil and gas installations are located.

Hovensa LLC said operations were normal at its 500,000 barrel-per-day refinery on the island of St. Croix but that the refinery's harbor and all other ports in the U.S. Virgin Islands had been closed because of Earl.

At noon EST (1600 GMT), the hurricane was 9O miles east-northeast of St. Thomas in the U.S. Virgin Islands and about 16O miles east of San Juan, Puerto Rico.

The hurricane buffeted the northernmost Leeward Islands of the Caribbean with fierce winds, driving rain and pounding waves as it passed on Monday.

The world's three largest cruise lines -- Carnival Corp, Royal Caribbean and Norwegian Cruise Line -- changed their Caribbean itineraries and rerouted at least seven ships to avoid the storm.

POWER OUTAGES, TREES TOPPLED

Residents on the island of St. Martin/St. Maarten, its two halves respectively administered by France and the Netherlands, said Earl's passage caused power outages and toppled trees.

"Now the wind is really blowing, incredibly strong ... I've seen a lot of tree damage ... I would certainly assume roofs off, I'm watching mine very carefully," Steve Wright, general manager of the Grand Case Beach Club in Grand Case, St. Martin, told Reuters.

"It's nothing that we haven't seen before but I'm surprised at the ferocity of the winds right now," he said.

There were no immediate reports of casualties.

In Antigua, some flooding in low-lying areas was reported. After the hurricane passed, Antigua and Barbuda Governor General Dame Louise Lake-Tack declared a national holiday to allow residents of the twin-island state to clean and mop up.

The hurricane center said hurricane conditions would spread westward into the Virgin Islands on Monday and possibly into Puerto Rico later in the day.

The ports of the U.S. Virgin Islands and the ports of Vieques, Culebra, Fajardo, and San Juan, Puerto Rico, were closed, the U.S. Coast Guard reported. Government offices and schools in eastern Puerto Rico were shut.

In the North Atlantic, Hurricane Danielle, a major Category 4 storm last week, was barely still a hurricane as its sustained winds fell to 75 mph. The storm was expected to lose its tropical characteristics later in the day. It was about 420 miles south southeast of Cape Race, Newfoundland.

The hurricane center said earlier a new Atlantic weather system carrying showers and thunderstorms, located about 1,050 miles east of the Lesser Antilles, had a 90 percent chance of becoming a tropical cyclone in the next 48 hours as it moved westward.

(Reporting by Pascal Fletcher, Tom Brown and Jane Sutton in Miami; Writing by Pascal Fletcher; Editing by Bill Trott)