Runners will start in chilly 36°F conditions — dress in layers for the corral and plan to shed early. Moderate humidity at 78% is worth noting for effort level, especially in later miles.
Race day forecast available in 46 days
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Distance: 26.2mi
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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.
The 2026 Seattle Marathon will be held on Sunday November 29, 2026.
Is the Seattle Marathon a Boston Marathon Qualifier?
Yes, the Seattle Marathon is an official Boston Marathon qualifier.
What will the weather be like for the 2026 Seattle Marathon?
The forecast calls for a high of 45°F and a low of 35°F with a 25% chance of rain. Check our detailed hourly forecast above for the best marathon race plan.
Historical Weather
Based on 25 years of data
Avg Temp
46°F
L:41° H:47°
RunScore
Conditions
Rain Freq
36%
9 of 25 yrs
Wind9mph
Dew39°F
Temperature History
Range of temperatures during race hours for each year.
