Runbelievable Half Marathon
Race Day Weather
Comfortable temps
Starting at 61°F, heat will be a factor from the gun — go out conservative and stay on top of hydration. Light winds shouldn't be a major factor for pacing. High humidity (82%) will make it harder to cool down through sweat — increase fluid intake accordingly.
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Race Info
Runbelievable Half Marathon is a superhero-themed race held along the Long Beach shoreline near 5400 E Ocean Blvd. The course follows a flat, mostly out-and-back beach path shared with several other CaliFlow Runs events at the same venue. Runners are encouraged to wear capes and costumes, and the event also includes 5K, 10K, one-mile, and kids' distances. The race debuted June 6, 2026, and its second edition is scheduled for June 6, 2027.
