HAMILTON (Reuters) - Hurricane Bill weakened slightly on Friday as it followed a path between the U.S. East Coast and Bermuda, but the tiny British territory warned its residents to prepare for dangerous surf and possible flooding.
The core of the massive storm was expected to stay over the open Atlantic as it passes west of Bermuda early on Saturday and east of Cape Cod in Massachusetts early on Sunday. Bill was forecast to weaken to a tropical storm before skirting eastern Canada later on Sunday.
The North American energy market was watching Bill because it could threaten oil and natural gas platforms and refineries in eastern Canada.
The U.S. National Hurricane Centre said Bill, the first hurricane of the 2009 Atlantic season, had become a little less organized and its maximum sustained winds had dropped slightly to 110 mph (175 kph).
It was a Category 2 storm on the five-step Saffir-Simpson scale of hurricane intensity and its strength was expected to fluctuate in the next day or two.
At 2 p.m. EDT (7 p.m. British time), the hurricane's centre was 290 miles (465 km) south-southwest of Bermuda. Bill was moving northwest and was forecast to curve to the north and then northeast as it approached cooler waters that would start to sap its strength.
The Miami-based hurricane centre said Bermuda, a 20 square mile (53 sq km) British overseas territory that is a centre for the global insurance industry, could expect "significant coastal flooding ... over the next day or two due to large and dangerous breaking waves generated by the hurricane."
Bermudian authorities warned the island's 68,000 inhabitants to be prepared.
"Stay off the roads, stay off the beaches and stay close to home -- please think safety first," Bermuda's Acting Home Affairs Minister Walter Roban urged.
U.S. Secretary of State Hillary Clinton and her husband, former President Bill Clinton, wrapped up a brief private vacation on Bermuda and left the island ahead of the storm on Thursday, the State Department said.
Hurricane Bill's closest point of approach to Bermuda was expected to be on Saturday morning when the eye of the hurricane would be passing around 230 miles (370 km) to the west.
The hurricane centre said large swells generated by the hurricane -- which whipped up dangerous surf and rip-currents -- were already affecting Bermuda, the Bahamas, Puerto Rico and Hispaniola. Over the next day or two such swells would also be experienced on the U.S. East Coast and Canada's Atlantic maritime provinces.
High waves along the north coast of the Dominican Republic had caused some coastal flooding with damage to roads and houses.
The U.S. forecasters were also keeping watch on a small disturbance off the Atlantic coast of Africa, about 525 miles (840 km) southwest of the Cape Verde Islands.
Any development would be slow and there was less than a 30 percent chance it would grow into a tropical cyclone in the next two days, they said.
(Additional reporting by Scott DiSavino in New York, Pascal Fletcher in Miami and Sue Pleming in Washington; Writing by Jane Sutton; Editing by Pascal Fletcher and Vicki Allen)
