Charles River Marathon Invitational
Race Day Weather
Mild rain, steady conditions ahead
Runners will face a steady temperature range of 64°F to 67°F with high humidity at 89%. Moderate rain is expected, which may create a slippery surface, so caution is advised. The wind, light at 8 mph from the ESE, will have minimal impact on performance. Runners should consider adjusting their pace conservatively and ensure hydration due to the warm conditions.
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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.