The coolest-weather marathons in the US
Heat is the silent time-killer — every degree above about 55°F slowly bleeds minutes from your finish. We ranked marathons by their 10-year average race-morning temperature and dew point so you can pick a race where the weather is on your side. These 10 run the coolest.
- 1Allianz Richmond MarathonNov 14, 2026Richmond, VA · Climate score 10.0/1037°F / 31°F dew
- 2Mercedes-Benz Marathon BirminghamFeb 14, 2027Birmingham, AL · Climate score 10.0/1038°F / 31°F dew
- 3California International MarathonDec 6, 2026Sacramento, CA · Climate score 10.0/1041°F / 40°F dew
- 4TIAA Philadelphia MarathonNov 22, 2026Philadelphia, PA · Climate score 10.0/1042°F / 34°F dew
- 5CNO Financial Indianapolis MonumentalNov 7, 2026Indianapolis, IN · Climate score 10.0/1044°F / 38°F dew
- 6Eugene MarathonApr 25, 2027Eugene, OR · Climate score 10.0/1045°F / 43°F dew
- 7Detroit Free Press MarathonOct 18, 2026Detroit, MI · Climate score 10.0/1046°F / 39°F dew
- 8Ascension Seton Austin MarathonFeb 14, 2027Austin, TX · Climate score 10.0/1046°F / 42°F dew
- 9Chevron Houston MarathonJan 17, 2027Houston, TX · Climate score 10.0/1047°F / 39°F dew
- 10Marine Corps MarathonOct 25, 2026Arlington, VA · Climate score 10.0/1048°F / 42°F dew
Race-day temp (10-yr) · ranked live from the Green Score catalog.
Frequently asked
- What temperature is best for running a marathon?
- Most research points to a sweet spot around 45–55°F for marathon performance. Above ~60°F, finish times degrade measurably; dew point matters as much as temperature because it limits how well you cool by sweating.
- How is race-day weather estimated?
- We pull 10 years of historical temperature and dew point at each race's start location and start hour, then average them. It's a climatology, not a forecast — but it tells you what to expect in a typical year.
Not sure which fits you? Get a finish probability and your earliest safe race date.
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