Oscar became the eighth hurricane of the Atlantic season on Sunday, but forecasters said it posed no threat to land, although Bermuda residents were told to expect rough seas in the days ahead.
Oscar already packs sustained winds around 60 miles per hour.
"Environmental conditions appear conducive for further development and this system will likely become a tropical or subtropical cyclone later today or tonight while it moves generally northward over the central Atlantic". Officials at the hurricane center said it was about 815 miles east-southeast of Bermuda and moving slowly west, but was expected to turn northwest soon.
The storm had top sustained winds of 60 miles per hour (95 kph).
There are no coastal watches or warnings in effect.
Tropical Storm Oscar has been upgraded to a hurricane in the central Atlantic. Oscar is forecast to begin moving toward the north and then the northeast by early next week.
Oscar is the 15th named storm of the six-month Atlantic hurricane season that ends November 30.