The Jackson Hole Marathon Events are scheduled to take advantage of the beautiful late summer colors of the aspens and cottonwoods. Participants should be prepared for a chilly morning (usually around 40F) and warm temperatures, sometimes hot, around midday. The sun is intense at altitude, so it may feel warmer than the actual actual temperature indicates. Sunscreen is a good idea, as well. It is important to stay hydrated and know that you’ll be running at altitude. Here is a link to some High Altitude Health Tips.
Average temperatures for Labor Day Weekend:
Highs ~ 72F/ 22C
Lows ~ 42F/ 5C