MIAMI, Oct. 14 (UPI) -- Omar strengthened into a Category 1 hurricane late Tuesday as it chugged across the Caribbean toward Puerto Rico.
At 11 p.m. EDT, the storm's maximum sustained winds were about 75 mph, up from 40 mph at 11 a.m., the National Hurricane Center in Miami reported. Omar was expected to gain strength further Wednesday.
Hurricane warnings were posted for the U.S. Virgin Islands and for the British Virgins and St. Martin, Saba, St. Eustatius, St. Barthelmy, Anguilla, St. Kitts and Nevis, Antigua, Barbuda and Montserrat. A tropical storm warning and hurricane watch was in effect for Puerto Rico, and forecasters said that was likely to be a hurricane warning by Wednesday morning.
Omar was 315 miles south-southwest of San Juan, Puerto Rico, moving northeasterly at 6 mph, the center said. Hurricane winds extended 15 miles from the center and tropical storm winds 90 miles.
The storm was expected to hit the northern Leeward Islands late Wednesday.
Forecasters warned Omar is likely to bring heavy rain in Puerto Rico and smaller islands in its path and to the northern coast of Venezuela. The rain could trigger flash floods.
The storm was also expected to bring heavy swells and battering surf.