MIAMI Tropical Storm Erika formed in the Atlantic Ocean east of the Caribbean's northern Leeward Islands on Tuesday and could become a hurricane, the U.S. National Hurricane Center said.
The fifth tropical storm of the 2009 Atlantic hurricane season had sustained winds of 50 miles per hour (80 km per hour) and was located 390 miles east of the islands at 5 p.m. EDT (2100 GMT), the hurricane center said.
The storm's most likely track would see it avoid the Gulf of Mexico oil patch and take it north of the Caribbean islands, just east of the Bahamas on a curving path toward the U.S. east coast, according to the hurricane center.
It was expected to encounter strong wind shear -- a difference in wind speeds at different altitudes that can tear apart nascent cyclones -- in about two days and the official forecast did not show it becoming a hurricane within the next five days.
But there was still a good chance of Erika reaching hurricane strength eventually, with sustained winds of 74 mph.
"Almost all of the reliable intensity guidance show Erika eventually becoming a hurricane, despite the shear," the hurricane center said in a statement.