Thumb Coast Marathon
Race Day Weather
Cool start, steady wind
Runners will face temperatures starting at 38°F and rising to 47°F. With a light wind from the WSW at 10 mph, runners may feel a chill, especially early on. Adjusting pace conservatively during the first half is advisable, and a throwaway layer could be beneficial during pre-race. Humidity will be moderate at 69%.
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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
