Thumb Coast Marathon
Race Day Weather
Cool conditions, slight wind chill
Runners will face a steady temperature rise from 37°F to 47°F, with light winds from the WSW at 10 mph. Humidity will hover around 69%, creating a cooler feel. A conservative pace is recommended for the early miles to accommodate the wind chill and maintain energy throughout the race.
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Race Info
The Thumb Coast Marathon is a point-to-point race along Lake Huron's Saginaw Bay shoreline in Michigan's Thumb region, starting in downtown Caseville and finishing on Main Street in Port Austin. The USATF-certified course is flat and fully paved, gaining about 265 feet over 26.2 miles and passing Point Crescent State Park near the finish. It is a Boston Qualifier: 8.9% of finishers in the 2025 inaugural race hit a BQ time, and the course carries a 99.45 course score, the second-fastest marathon course in Michigan. Race weekend also includes a half marathon starting at Sleeper State Park and a 5K in downtown Port Austin. Source
