Grand Ridge Half Marathon
Grand Ridge Half Marathon race day weather
Cool start — fast day potential, warming through the race
A cool 50°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temperatures rising to 63°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. High humidity (81%) will make it harder to cool down through sweat — increase fluid intake accordingly.
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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 Grand Ridge Half Marathon
The Grand Ridge Half Marathon is one lap of the longer loop in Grand Ridge Park in Issaquah, and the organizers describe it as closer to 14 miles than 13. It leaves the Issaquah-Preston Trail High Point Way Trailhead, climbs rocky switchbacks to the ridge, detours onto the Flowing Fir Trail and then runs an out-and-back to the Duthie aid station. The trail is graded gently but still packs in steady climbing through Cascade foothill forest.
