Mo Cowbell Marathon

This edition is listed as Marathon in St. Charles, Missouri, USA.

When we have race morning history, use that range for planning, not as a promise. Inside about 14 days, the live forecast on this page is the better read. We do not invent a start-hour number when history is not loaded here.

Inside about 14 days, use the live forecast on this page. Further out, use typical conditions for this race window, not a locked number. Set effort from the forecast when race day is close enough to trust it.

Heat, humidity, wind or a lumpier day than you hoped all raise the chance of a late fade. If the start feels easy, don't spend it. Back off early, and hold even effort even if that means slower than the A-goal. The preview on this page is the starting point. Full personalised splits sit in Race Pass or Pro.

About 145 m of climbing and 146 m of descent. Rolling. Almost all of it sits within 2%. No steep grades over 6%. 5 climbs.

It is an estimate of how the course and conditions could move your baseline. Your body still decides the rest: heat adaptation, fuelling, prep, mindset, how you race, and whether you can draft.

The free page covers conditions, course context and a finish preview. Full personalised pacing and weather-adjusted splits sit in Race Pass or Pro.