NEW : Ike goes from 80-mph winds to peak winds in six hours . Hanna to the Bahamas , and regain hurricane status . Hanna expected to make U.S. waters by Friday or Saturday .
NEW : Ike goes from 80-mph winds to 135-mph winds in six hours . Hanna to pound Bahamas , could regain hurricane strength . Hanna expected to make U.S. landfall by Friday or Saturday .