Story highlights

NEW: Leslie is downgraded to a tropical storm

NEW: But forecasters say it will likely return to hurricane strength

Forecasters warn of life-threatening rip currents on U.S. beaches from Leslie

(CNN) —  

Hurricane Leslie lost power as it idled over the ocean Friday, weakening into a tropical storm that appeared likely to miss Bermuda.

Forecasters warned that large waves and dangerous rip currents would still pose a threat to coastal areas, and near-tropical-storm-force winds would lash the island Sunday.

The storm also was likely to regain hurricane strength as it moves off the pool of cool ocean water it created for itself while idling for hours more than 400 miles away from Bermuda, the National Hurricane Center said.

However, forecast models indicated it would likely remain a Category 1 storm, rather than the more powerful Category 2 storm previously forecast.

A tropical storm watch remained in effect Friday in Bermuda, where schools were closed and government offices were preparing to close early to give residents more time to prepare.

Government officials are planning to close the damage-prone causeway linking the main portion of the country with St. David’s Island, where its international airport is located, on Saturday, the Emergency Measures Organization said. Sea ferry service will be suspended Friday night, the agency said.

Wayne Perinchief, Bermuda’s national security minister, said Thursday that officials were planning a “well-coordinated” response to any problems caused by the storm.

The storm is already dishing out heavy swells and dangerous currents in coastal areas of Bermuda, the Leeward Islands, Puerto Rico, the Virgin Islands and the U.S. East Coast from Florida to New York, the National Weather Service said.

Forecasters warned of potentially deadly rip currents that can pull even the strongest swimmers out to sea quickly. The agency warned beachgoers to stay out of the surf until the danger passes.

Another hurricane, Michael, formed late Wednesday in the eastern Atlantic. By Thursday, it had become the first major hurricane of the season as it strengthened to a Category 2, with winds of near 110 mph.

Michael is the seventh hurricane of the 2012 season, but posed no immediate threat to land, the hurricane center said.

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