Tropical Storm Dean formed in the Atlantic Ocean midway between Africa and the Caribbean on Tuesday and could become the first Atlantic hurricane of the 2007 season later in the week, U.S. forecasters said.

The fourth cyclone of the year was days away from any contact with land.

But the U.S. National Hurricane Center's forecast track had it reaching the Lesser Antilles -- the islands of the eastern Caribbean -- late this week. The Lesser Antilles stretch from Trinidad in the south to the British and U.S. Virgin Islands in the north.

At 11 a.m. EDT (1500 GMT), the center of Dean was located about 1,490 miles (2,400 km) east of the Lesser Antilles and was charging west at about 23 miles per hour (37 kph), the hurricane center said.

Dean's top sustained winds were about 40 mph (64 kph). It was expected to gradually strength and become a hurricane with winds of at least 74 mph (119 kph) by Friday.

The storm could be a Category 3 hurricane with winds of up to 127 mph (204 kph) in five days, forecasters said. The strongest and most dangerous hurricanes, known as major hurricanes, are Category 3 to Category 5 storms.

Computer models disagreed on Dean's long-range destination.

One carried it into the Caribbean Sea well south of Jamaica, while another had it hitting the northernmost Lesser Antilles and curving north into the Atlantic Ocean east of the Bahamas, hundreds of miles from the Florida coast.

The Miami-based National Hurricane Center was also eyeing a weather system in the south-central Gulf of Mexico that could become a tropical depression, the forerunner of a tropical storm, in the near future.

Energy markets were keeping a close eye on the system, as roughly a third of U.S. domestic oil and gas production comes from the Gulf of Mexico, while residents of southern Texas and northeastern Mexico were also told to be on alert.

Forecasters have been warning residents of the Caribbean and the U.S. East and Gulf coasts that the peak of the hurricane season is coming. The period from Aug. 20 to mid-October is historically the busiest time for Atlantic hurricanes.