Seattle Half Marathon
Seattle Half Marathon race day weather
Cold start — layer up
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.
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A mile-by-mile breakdown of where your time goes, weather-adjusted splits, fueling timeline with aid stations, packing checklist, carb tracker, spectator guide, all built around your goal and race-day conditions.
About the Seattle Half Marathon
The Seattle Half Marathon starts at Seattle Center and finishes at Bell Harbor Pier 66 on the downtown waterfront. The route runs east to Lake Union, follows the Eastlake shoreline north and returns along Northlake Way past Gas Works Park, then continues along the ship canal through Fremont. The last miles come back on the Elliott Bay Trail through Myrtle Edwards Park to the finish at the water. It runs on the Sunday of race weekend, alongside the full marathon.
