Seattle Marathon
Race Day Weather
Cool start, moderate humidity
Runners will face a temperature trend from 35°F at the start to a high of 42°F. With an average humidity of 78% and light winds from the SE at 5 mph, conditions will be comfortable but may feel cooler. Runners should dress in layers and consider hydration strategies, especially as temperatures rise.
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Race Info
The Seattle Marathon starts at Seattle Center and finishes at Bell Harbor Pier 66 on the downtown waterfront. A new course introduced for the 2025 race takes runners north along Lake Union's Eastlake shore, across the Montlake Bridge, and through Interlaken Park into the Washington Park Arboretum and the University of Washington campus, then west past Gas Works Park and through Fremont before finishing on the waterfront. First run in 1970 by a group of University of Washington friends, it's the oldest marathon in the Pacific Northwest and still pairs a half marathon with the full on race morning.
