MIAMI (AP) — Tropical Storm Bonnie has formed with winds of 40 mph (65 kph) in the eastern Caribbean, on a course that could take it into the BP oil spill zone.

An Air Force plane sent to study the storm determined it had reached tropical storm strength Thursday.

The storm system was raking the Turks and Caicos Islands and the southern Bahamas, and it had caused flooding in Puerto Rico, the Dominican Republic and Haiti.

The system is expected to bring heavy winds and rains to the Florida Keys in the next few days.

A forecast map shows that the storm could reach the area of the Gulf of Mexico around the massive oil spill by sometime this weekend, but forecasters say that the path of a storm can be difficult to predict.