In Chatham, Mass., boaters and fisherman have moored their boats. Some have taken them out of the water completely.
"People need to know the seriousness of Mother Nature," Hawkins said. "It's beautiful to watch but they need to be careful."
After earning its name last Saturday when it became a tropical storm, Hurricane Bill became the first hurricane of the Atlantic storm season by Monday morning. The hurricane strengthened to a Category 4 hurricane by Wednesday, with sustained winds up to 135 miles per hour.
On Thursday morning, it weakened slightly to a Category 3, with winds decreasing to 120 mph.
"Weakening is expected to begin on Sunday as Bill moves over cooler waters," the National Hurricane Center's update said Saturday evening.
ABC News' Marysol Castro, Stephanie Sy, Jeffrey Kofman, Gerard McNiff, Jan Simmonds, Sharyn Alfonsi and The Associated Press contributed to this report.