Green River Marathon
Race Day Weather
Comfortable temps
Mild 55°F temps at gun time mean comfortable early miles without overheating risk. Temperatures rising to 65°F through the course will gradually increase perceived effort in the second half. Light winds shouldn't be a major factor for pacing. Moderate humidity at 66% is worth noting for effort level, especially in later miles.
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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.
