Subtropical Storm Fay formed in the Atlantic on Friday as forecasters issued a tropical storm watch for Bermuda.
The U.S. National Hurricane Center in Miami said the storm was 525 miles south of Bermuda on Friday afternoon. It was moving north-northwest at 12 mph, with maximum sustained winds of 40 mph.
The Hurricane Center said the storm was expected to strengthen over the weekend and to produce rainfall of 2 to 4 inches in Bermuda as well as generate large swells along the island's southern coast.
Forecasters said Fay likely would turn toward the north and increase in speed today, then turn toward the northeast Sunday, staying well out in the Atlantic.
Bermuda's government weather service said that the storm was expected to pass southeast of Bermuda early Sunday.