In its 5 p.m. EDT update, the National Hurricane Center said Dorian was about 505 miles west of the Cape Verde Islands, moving west-northwest at 20 mph, with top sustained winds of 50 mph.
Dorian was expected to follow the same general motion Wednesday and Thursday, and then lose strength Thursday as it moves over colder water. There is a chance the storm could subsequently gain strength as it returns to warmer water.
Tropical storm-force winds extended 45 miles from the storm's center.
No coastal watches or warnings were in effect.