Surging north, Hurricane Bill threatens Bermuda, East Coast

Forecasters said Bill should begin pushing large swells toward Bermuda and parts of the southeastern US coast by the weekend, but it wasn’t yet clear how close the storm will come to land.

In New England, the National Weather Service office in Taunton said the hurricane is expected to pass about 200 miles east of Nantucket Sunday, but it warned that dangerous surf and rip currents will make conditions treacherous at south-facing beaches. Waves as large as 20 feet expected east of Nantucket, reaching up to 50 feet in the rich fishing grounds of Georges Bank and Grand Banks.

The National Hurricane Center also said people in the Leeward Islands should keep an eye on the storm, though its core was expected to pass well to the northeast of the chain in the next 24 hours.

Fishermen in Antigua were advised to dock their boats.

As strong as Bill already is, it could get stronger because it’s traveling into warmer waters in the Atlantic that could intensify the storm, said senior hurricane specialist Lixion Avila.

“The warm ocean is like the fuel for car,’’ Avila said yesterday. “If you get high-octane gas you get more power - that’s what warmer water does.’’

Bill was maintaining a top wind speed of 135 miles per hour yesterday, hours after it became a Category 4 storm, and forecasters said it could get stronger. The storm’s center was located 335 miles east of the Leeward Islands and it was moving west-northwest near 20 miles per hour.

The most significant threat could be to Bermuda, which the storm could pass in three or four days, forecasters said.

But it also could move directly between Bermuda and the eastern coast of the United States without making landfall.

It was too early to tell if Bill would veer close to shore over the weekend or swing away from the East Coast of the United States, but the five-day forecast predicted its center would pass well offshore of the North Carolina-Virginia line Saturday.