MIAMI (Reuters)—Powerful Hurricane Bill, a dangerous Category 4 storm with 135 mph winds, raged across the open Atlantic Wednesday, days from land but on a path that could menace Canada's eastern province next week.

Still located east of the Leeward Islands of the Caribbean, the first hurricane of the 2009 Atlantic season was no threat to oil and gas installations in the Gulf of Mexico and on its current forecast track would sweep between the U.S. East Coast and Bermuda, well offshore.

Residents of Bermuda, a British territory and reinsurance capital in the mid-Atlantic, were warned to be prepared for the storm. The latest forecast track issued by the U.S. National Hurricane Center would take Bill more than 100 miles to the west.

But Bill's massive size—tropical storm-force winds of 39 to 73 mph extend up to 175 miles from its center—meant Bermuda would still feel it, forecasters said.

"As strong as this hurricane is and as large as this hurricane is, Bermuda is still going to have tremendous wave impacts," said Max Mayfield, former director of the U.S. National Hurricane Center.

Forecasters said Bill might get stronger. Hurricanes of Category 3 or higher on the five-step Saffir-Simpson intensity scale are considered "major" and are the most destructive type.

Heavy surf expected on U.S. East Coast

The well-defined eye of Bill was located about 1,080 miles south-southeast of Bermuda at 11 a.m. on Wednesday and the system was moving toward the west-northwest at 18 mph, the hurricane center said.

Its curving forecast track would take it to a position hundreds of miles east of Miami by early Friday, and well off New York by Sunday.

"How close it gets to the New England coast, there's still the usual uncertainty in that long time period," Mr. Mayfield said. "But the core of the hurricane—most of the models indicate it's going to remain off the coast."

He said the U.S. East Coast was still likely to see heavy surf by the weekend, a warning to surfers and swimmers.

The forecast track shows it skirting the Nova Scotia coast on Sunday and just south of Newfoundland as a Category 1 hurricane by Monday. But five days in advance, the forecast has an average error of several hundred miles.

Energy traders still had a wary eye on the remnants of Tropical Storm Ana drifting toward the warm waters of the eastern Gulf of Mexico on Wednesday.

The hurricane center gave the system, which was producing showers over the northwestern Bahamas and Florida, a low chance, less than 30%, of becoming a cyclone again.