Big Sky Marathon

Ennis, MT, USA · July 12, 2026
partly-cloudy-day50°·73° high·Light·Dry
9
Weather
Pace Calc
Course
Race Info
FAQ
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Race Day Weather

partly-cloudy-day
50°at start
75° high
Light
Dry

Cool start, warming trend ahead

Runners will face a temperature rise from 49°F to 74°F during the race, with a gentle breeze at 7 mph from the SSW. Humidity will remain moderate at 50%, with a dew point of 43°F. Participants are advised to start conservatively and adjust their pace as temperatures climb.

Race day forecast available in 14 days
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Pace Calculator

Distance: 26.2mi
0:00:00
HH:MM:SS
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Race Info

The Big Sky Marathon offers runners a thrilling point-to-point course through Montana's high mountains, starting at approximately 8,600 feet elevation and descending into the charming town of Ennis. This trail marathon is part of the Greater Yellowstone Adventure Series and features stunning mountain views throughout the challenging downhill route. The race is known as one of the longest downhill road marathons on the planet, making it a bucket list event for serious runners.

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Area Map

Course Map

Course Map Unavailable

We don't have course map data for Big Sky Marathon yet. If you have a GPX file (or other format) for this race, we'd love to add it!

FAQ

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When is the 2026 Big Sky Marathon?

The 2026 Big Sky Marathon will be held on Sunday July 12, 2026.

What will the weather be like for the 2026 Big Sky Marathon?

The forecast calls for a high of 77°F and a low of 48°F with a 7% chance of rain.

Historical Weather

Based on 2 years of data
Avg Temp
87°F
L:55° H:87°
RunScore
7
Conditions
Rain Freq
0%
0 of 2 yrs
Wind10mph
Dew34°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore

2025 Big Sky Marathon

Clear conditions throughout the day.

2025
clear-day
55°/86°-
8

2024 Big Sky Marathon

Clear conditions throughout the day.

2024
clear-day
56°/89°-
8

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Free guidesMarathon Fueling Guide·Carb Loading Guide·Race Morning Guide·Race Day Gear Guide·Pacing Strategy Guide·Mental Strategy Guide

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