Charles River Marathon Invitational
Race Day Weather
Comfortable temps, adjust pace later
Runners will face temperatures starting at 55°F and gradually climbing to 70°F, with humidity averaging 71%. Wind will be light and variable, with a maximum of 5 mph, posing minimal impact on pace. As temperatures rise in the late laps, it is advisable for runners to adjust their pace conservatively and ensure adequate hydration.
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Race Info
The Charles River Marathon Invitational is an invitation-only marathon in Boston, run on the same USATF-certified, ten-lap Charles River loop as the Charles River Marathon. Entry requires having finished a certified marathon since January 2024 within 20 minutes of a Boston qualifying time, with a limited number of fundraiser entries available. First run in September 2025, it drew a 73% Boston-qualifying rate among finishers. The race benefits the RACE Cancer Foundation's cancer research fundraising.
