Residents of Bermuda installed storm shutters and hauled their yachts onto beaches in preparation for Tropical Storm Florence, which intensified Saturday and was expected to become a hurricane as it approaches the North Atlantic island.

Florence, which could become a hurricane as it moves over the open Atlantic on Sunday, was expected to reach the tiny British territory Monday, according to the National Hurricane Center in Miami. But it was too early to tell whether it will make a direct hit.

"It's probably not going to become a hurricane tonight, but it could become a hurricane tomorrow," said Stacy Stewart, a senior hurricane specialist at the center. It could be a Category 2 hurricane, which has winds of 96 to 110 mph, he said.

Click here to track Tropical Storm Florence.

Bermuda issued a hurricane watch and a tropical storm warning, and the government urged its 65,000 residents to take precautions. Part of Bermuda's volunteer army has been mobilized.

"We are asking residents to please stay home. We are urging the public's cooperation so that emergency vehicles will have free passage on the roads," Derrick Burgess, minister of public safety, said at a news conference. "Also, we are discouraging the public from sightseeing as this puts everyone at risk."

He also encouraged the public to stock up on hurricane supplies and secure their homes, lawn furniture and any other loose items which could be affected by high winds.

In boatyards and marinas in Bermuda — a wealthy island chain 640 miles east of the U.S. coast — boat owners dragged their yachts onto beaches or secured their moorings.

At Pitts Bay marina, Bermudian Alan Hughes moved his 17-foot Boston Whaler away from the dock wall and tied it down.

"We are obviously concerned and cautious. It will be a tidal issue, with up to five or six foot tidal swells," he said.

At the Fairmont Hamilton Princess, the hotel distributed a disaster plan — which included provisions for evacuation — and told guests that patio furniture would be removed from their rooms.

Roy Riggio, a 72-year-old volunteer counselor with Medicare from New Canaan, Conn., said he and his wife, Barbara, arrived in Bermuda on Friday.

As other guests at the Fairmont were leaving, Riggio said he didn't believe the hurricane would deter him and his wife and he wanted a "window seat" at the hotel's restaurant on Sunday night to watch the storm.

"If not, I'm going to take pictures from my room — I have a room up at the top of the hotel — and I want to get some photos. I'm not a glutton for punishment, but it's exciting," he said.

The island's only airport, Bermuda International Airport, was to close at 9 p.m. EDT and was not expected to reopen until late Tuesday at the earliest, said Acting General Manager Aaron Adderley. Flights from New York and Miami scheduled to arrive late Saturday have been canceled.

Adderley said staff members were securing the airport and terminal building, boarding them up and laying sand bags because it is next to the ocean.

Ferries stopped running Saturday afternoon and bus service will end Sunday at 1 p.m.. Authorities have opened a shelter in the island's center, and the public utility has warned there may be power outages due to the high winds.

Public schools and government offices will be closed Monday.

Acting Police Commissioner Roseanda Young said arrangements have been made for tourists to leave after the airport shuts down, with commercial airlines and private jets helping out.

"All tourists have been given the opportunity to leave. Those still here have chosen to stay," she said.

The storm was expected to veer away from the U.S. coast as it turns north toward Bermuda, but forecasters said its large size could also create high surf and rip currents along parts of the eastern U.S. coast.

"Those waves will affect a good portion of the U.S. East Coast from basically Florida all the way up to the Cape Cod area" starting Sunday through the early part of next week, Stewart said. "When those large swells come rolling in to the coastline they tend to produce dangerous and potentially deadly rip currents."

Large ocean swells were affecting Bermuda and the northern coasts of the Caribbean islands, including Puerto Rico and the U.S. Virgin Islands, the hurricane center said.

The storm's sustained winds have slightly weakened to nearly 65 mph Saturday. Tropical storm force wind extended up to 345 miles from Florence's center.

At 8 p.m. EDT, the storm was centered about 430 miles south of Bermuda, where it has started to rain. It was moving northwest at about 13 mph.

Bermuda requires newly built houses to withstand sustained winds of 110 mph . It also has a sturdy infrastructure with many of its power and phone lines underground.

Hurricane Fabian killed four people when it struck in 2003 as the strongest storm to hit Bermuda in 50 years. Fabian, a Category 3 hurricane with 120 mph winds, tore the roofs off several homes and left many of Bermuda's famed golf courses in ruins.

Florence follows on the heels of Tropical Storm Ernesto, which was briefly the season's first hurricane before weakening and drenching the U.S. East Coast last week. The storm was blamed for nine deaths in the United States and two in Haiti.

Florence, the sixth named storm of the hurricane season, developed in the peak of hurricane season over warm Atlantic water, the source of energy for storm development this time of year. Although those waters are warm enough to spur storm intensification, forecasters said they are not as warm as last year's storm season, which had a record 28 named storms and 15 hurricanes, including Katrina.

The 2006 Atlantic hurricane season has not been as rough as initially feared. The National Hurricane Center lowered its forecast in August to between 12 and 15 named storms and seven to nine hurricanes.

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