The storm far from land over the Atlantic had been a hurricane earlier in the day before temporarily weakening to tropical storm status in the afternoon.
The hurricane could pick up more strength by the end of the week.
Danielle is located about 795 miles east of the Leeward Islands and is moving west-northwest near 18 mph.
Meanwhile in the Pacific, Tropical Storm Frank is moving slowly away from Mexico. Frank's maximum sustained winds are near 65 mph. The storm is located about 145 miles southwest of Lazaro Cardenas, Mexico, and is moving west-northwest.