Green River Marathon
Race Day Weather
Cool start, warming potential
Runners will face temperatures starting at 55°F and climbing to 65°F, with humidity around 66%. Light winds from the W will provide a negligible effect. Given the rising temperatures, pacing adjustments and hydration strategies should be implemented, especially as the heat sets in.
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Race Info
The Green River Marathon is a free, donation-supported marathon, half marathon, and 50K held each June in Kent, Washington. The course follows the Green River Trail as an out-and-back route starting and finishing at Three Friends Fishing Hole. It is a USATF-certified Boston qualifier and has run annually since 1997, reaching its 31st running in 2027. The race is organized entirely by volunteers, with no entry fee, official awards, or paid staff.