Aspen Backcountry 50K

Aspen, CO, USA · July 31, 2027·
partly-cloudy-day49°·69° high·Light·Dry
7
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Race Day Weather

partly-cloudy-day
49°at start
71° high
Light
Dry
Your goal
0:00:00

Cool start — fast day potential, big temp swing, chance of rain

A cool 49°F at the start line is ideal for fast times — expect to warm up quickly once you're moving. Temps will climb significantly to 71°F by later miles, so expect fading conditions as the race progresses. Light winds shouldn't be a major factor for pacing. There's a chance of rain, so have a backup gear plan ready.

Race day forecast available in 272 days
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Pace Calculator

31.1mi
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Get forecast alerts for Aspen Backcountry 50K

We'll text or email you when the forecast shifts — so you can adjust gear, pacing, and strategy. Max one per day.

Race Plan

Get your personalized Aspen Backcountry 50K race plan

A mile-by-mile breakdown of where your time goes, weather-adjusted splits, fueling timeline with aid stations, packing checklist, carb tracker, spectator guide, all built around your goal and race-day conditions.

Race Pace
Weather Splits
Nutrition
Gear & Packing
T-Minus
Carb Tracker
Spectator Guide
Race Band

Race Info

The Aspen Backcountry 50K starts and finishes at Rio Grande Park in Aspen on the Saturday of race weekend. It follows the marathon course through Henry Stein Park, Four Corners, Hummingbird, Hunter Creek and Smugglers, and adds an out-and-back to McNamara Hut, part of the 10th Mountain Division hut system. The route runs almost entirely on dirt trails with long climbs and descents above town, and tops out above 10,000 feet with views of the Elk Mountains.

Race weekend

Saturday, July 31
6:00 AM50K (31.1 mi)
7:30 AMMarathon (26.2 mi)8:00 AMHeavy Half Marathon (13.1 mi)

FAQ

When is the 2027 Aspen Backcountry 50K?

The 2027 Aspen Backcountry 50K will be held on Saturday July 31, 2027.

What is the time limit for the Aspen Backcountry 50K?

The time limit for the Aspen Backcountry 50K is 10 hours.

What will the weather be like for the 2027 Aspen Backcountry 50K?

The forecast calls for a high of 72°F and a low of 48°F with a 11% chance of rain. Check our detailed hourly forecast above for the best 50K race plan.

Historical Weather

Based on 5 years of data
Avg Temp
61°F
L:51° H:72°
RunScore
7
Conditions
Rain Freq
40%
2 of 5 yrs
Wind5mph
Dew42°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScoreResults
2026
clear-night
51°/79°-
7
2025
partly-cloudy-night
48°/73°Light
8
2023
partly-cloudy-night
48°/69°-
8
2022
partly-cloudy-night
48°/73°-
7
2019
cloudy
62°/65°Light
7