Re: Best week to sail in MA
The club cruises can fill up harbors, particularly if it's the New York Yacht Club. We've run into them a number of times at Nantucket, Edgartown, and Cuttyhunk. It seems these guys favor late July thru early August.
Later in August is probably safer. Water temps hit their peak as kids return to school and family boats are laid up for the winter. After labor day, amenities, like launch service at Block Island's Salt Pond, begin to dry up fast. By mid September, there is quite a scene in Newport during the boat show.