Autumn Run

Buena Vista, CO, USA · September 18, 2027·

60°·69° high·Light·Dry

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Race Day Weather

60°at start

74° high

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Dry

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Warm start, steady conditions

Runners will face a temperature rise from 60°F at the start to 69°F at the finish. With light winds from the WSW at 7 mph, conditions should remain comfortable. The low humidity at 37% allows for a more favorable performance, but runners should still stay hydrated as temperatures increase.

Race day forecast available in 315 days

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Distance: 13.1mi

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Race Info

The Autumn Run takes place on the third Saturday of September in Buena Vista, Colorado, in the upper Arkansas River Valley below the Collegiate Peaks. The half marathon starts near Cottonwood Lake and finishes at McPhelemy Park. A 10K, 5K, and free kids' fun run share the same race weekend. Source

Website

Race weekend

Saturday, September 18

9:15 AMHalf Marathon (13.1 mi)

9:30 AM10K (6.2 mi)

9:30 AM5K (3.1 mi)

Course Map

FAQ

When is the 2027 Autumn Run?

The 2027 Autumn Run will be held on Saturday September 18, 2027.

Is the Autumn Run a Boston Marathon Qualifier?

No, the Autumn Run is NOT a Boston Marathon qualifier.

What is the time limit for the Autumn Run?

The time limit for the Autumn Run is 2:00 PM hours.

What will the weather be like for the 2027 Autumn Run?

The forecast calls for a high of 75°F and a low of 46°F with a 4% chance of rain.

Historical Weather

Based on 9 years of data

Avg Temp

57°F

L:51° H:62°

RunScore

Conditions

Rain Freq

11%

1 of 9 yrs

Wind5mph

Dew30°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 Autumn Run Partly cloudy throughout the day with morning rain. 2026	50°/61°	Light	43°
2025 Autumn Run Partly cloudy throughout the day with afternoon rain. 2025	52°/60°	-	37°
2024 Autumn Run Becoming cloudy in the afternoon with late afternoon rain. 2024	54°/65°	-	28°
2023 Autumn Run Clear conditions throughout the day. 2023	44°/53°	-	36°
2022 Autumn Run Partly cloudy throughout the day. 2022	52°/64°	-	34°
2019 Autumn Run Clear conditions throughout the day. 2019	50°/62°	-	16°
2018 Autumn Run Clear conditions throughout the day. 2018	61°/71°	-	20°
2017 Autumn Run Partly cloudy throughout the day. 2017	52°/60°	-	31°
2016 Autumn Run Clear conditions throughout the day. 2016	48°/59°	-	29°

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