MIAMI (AP) _ Tropical storm Bonnie, strengthening as it skirts near Puerto Rico, could threaten the southeastern U.S. coast as a major hurricane within three days, forecasters said today.

``Definitely, it's getting stronger,'' said Jerry Jarrell, director of National Hurricane Center. ``People along the southeastern U.S. should pay attention to its progress.''

Late this morning, Bonnie was centered in the Atlantic north-northeast of Puerto Rico on a course that will take it east of the Bahamas toward the Southeastern United States as early as Monday.

Wind speed had strengthened to 65 mph. A weather disturbance becomes a named tropical storm when sustained winds reach 39 mph and a hurricane when winds reach 74 mph. Bonnie would be the first hurricane of this year's Atlantic hurricane season.