Marathons Will Shift Race Dates to Combat Rising Heat

Organizers are rescheduling events and shortening routes as rising temperatures make the 26.2-mile distance more dangerous.

Updated on Oct. 2, 2026 in Running

Marathons Will Shift Race Dates to Combat Rising Heat

Live Poll

Should local event organizers reschedule outdoor races to prioritize runner safety during extreme heat?

Starting in 2027, the Twin Cities Marathon will move to late October to avoid extreme heat. This move follows a national trend of races shifting schedules to mitigate physiological risks for runners in a warming climate.

Why it matters

Climate change is driving up temperatures, making it physically difficult for runners to cool their bodies during exertion. As heat indices rise, organizers are forced to adapt traditional formats to ensure participant safety.

A study of 221 races shows that 46 of 51 U.S. marathons analyzed will lose optimal running conditions by 2045. Runners typically struggle to regulate body temperature once ambient levels exceed 60 degrees F.

The players

Climate Central

This independent organization of scientists and journalists conducts research and analysis on the impacts of climate change.

World Meteorological Organization

This United Nations agency coordinates international work on weather, climate, and water resources.

The details

Organizers are increasingly shifting start times to earlier in the morning and moving races to cooler months to bypass peak heat. In Los Angeles, officials offered participants the choice to stop after 18 miles, though fewer than 5% chose that option during the event.

The Twin Cities Marathon will move to late October in 2027.
The Earth recorded its hottest year on record in 2024.
The Twin Cities Marathon was canceled in 2023 due to heat.

Season Trajectory

This trend mirrors findings by Climate Central, which provides the data baseline forcing marathon organizers to reconsider traditional event scheduling. These shifts suggest that the standard fall and spring marathon calendars will continue to see disruptions due to extreme weather.

Runners should expect more races to implement early start times or offer shortened distances as heat mitigation becomes a standard safety protocol. Participation plans for fall marathons in the U.S. will likely require more flexibility as event dates shift in coming years.

The takeaway

Runners should prioritize monitoring local weather forecasts and heat index data when training for major endurance events. Adaptability in race-day strategy is becoming a necessary component for long-distance athletes.