ST. IGNACE, Mich. (AP) - The Mackinac Bridge has closed to traffic for the third time in a week because of ice falling from cables and towers. The bridge connecting Michigan's two peninsulas shut down again Sunday morning. It had reopened Saturday after a 20-hour closure and also was closed for several hours from Tuesday into Wednesday. MLive reports it's the fourth weather-related closure this year for the bridge that spans the Straits of Mackinac. It has closed 20 times for weather issues since 1995.