Heatwave Half Marathon/5K/10K

The Heatwave Half Marathon returns to St. Louis on Saturday, July 31, 2027. It's a mid-summer race, and the name isn't exactly a metaphor—running in St. Louis at the end of July means dealing with the full weight of the Missouri humidity, so you'll want to plan your hydration and pacing around the heat. The half marathon is the main event, but there are also 5K and 10K options on the same day, which gives you a few different ways to get your miles in depending on how much you're looking to push yourself.

Having a 5K and a 10K alongside the half makes it a good one to do with friends or family who might not be ready for thirteen miles. You can all head out to the same start and finish, just at different distances. If you've been training for a half, this is a solid chance to put that work to use; if you're just looking for a morning run with a crowd around you, the shorter distances keep it accessible. It's a single-day event, so everyone is out there at once.

Since it's a late-July race, the timing is something to keep in mind. The Heatwave Half Marathon takes place on Saturday, July 31, 2027, in St. Louis, Missouri, with the half marathon as the primary distance and 5K and 10K races running alongside it.