National Hurricane Center forecasters in Miami say a tropical depression has formed off the mid-Atlantic coast, but it's not expected to threaten land.

The National Weather Service counts the depression as the first of the 2009 Atlantic hurricane season, which officially begins June 1.

The depression's maximum sustained winds are near 35 mph. It is expected to become a tropical storm in the coming days.

Forecasters expect the depression to stay over the Atlantic and move toward the northeast near 17 mph over the next day or two.

At 11 a.m. EST Thursday, the depression was centered about 310 miles south of Providence, R.I., and about 635 southwest of Halifax, Nova Scotia.