Boulder Boulder

Boulder, CO, USA · May 25, 2026
partly-cloudy-day53°·65° high·Light·Dry
9
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Weather
Course
Race Info
FAQ
History

Race Day Weather

partly-cloudy-day
53°at start
67° high
Light
Dry

Cool start, warming trend

Runners will face a start-line temperature of 49°F, climbing to 67°F by the finish. Winds will be light at 6 mph from the SE, with occasional gusts up to 41 mph. With moderate humidity at 55%, pacing adjustments may be necessary as temperatures rise, encouraging runners to hydrate adequately and monitor their effort levels.

Race day forecast available in 23 days
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Race Info

The Bolder Boulder (styled as BOLDERBoulder and previously BolderBOULDER) is an annual 10-kilometer run in Boulder, Colorado. The most recent race featured over 54,000 runners, walkers, and wheelchair racers, making it the second largest 10k race in the US and the fifth largest road race in the world. It has one of the largest non-marathon prize purses in road racing. Wikipedia

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Course Map

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FAQ

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When is the 2026 Boulder Boulder?

The 2026 Boulder Boulder will be held on Monday May 25, 2026.

What will the weather be like for the 2026 Boulder Boulder?

The forecast calls for a high of 67°F and a low of 48°F with a 0% chance of rain.

Historical Weather

Based on 25 years of data
Avg Temp
66°F
L:50° H:67°
RunScore
8
Conditions
Rain Freq
12%
3 of 25 yrs
Wind8mph
Dew38°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore

2025 Boulder Boulder

Partly cloudy throughout the day with rain.

2025
cloudy
50°/61°-
8

2024 Boulder Boulder

Clear conditions throughout the day.

2024
clear-day
55°/74°-
8

2023 Boulder Boulder

Clear conditions throughout the day.

2023
clear-day
54°/77°-
8

2022 Boulder Boulder

Clearing in the afternoon with early morning rain.

2022
cloudy
50°/62°-
8

2021 Boulder Boulder

Becoming cloudy in the afternoon with late afternoon rain.

2021
clear-day
53°/63°-
8

2020 Boulder Boulder

Clear conditions throughout the day.

2020
clear-day
52°/77°-
8

2019 Boulder Boulder

Partly cloudy throughout the day with rain.

2019
partly-cloudy-day
42°/56°-
9

2018 Boulder Boulder

Partly cloudy throughout the day with afternoon rain.

2018
cloudy
59°/64°-
8

2017 Boulder Boulder

Becoming cloudy in the afternoon with rain.

2017
clear-day
50°/67°-
9

2016 Boulder Boulder

Clear conditions throughout the day with afternoon rain.

2016
clear-day
52°/77°-
8

2015 Boulder Boulder

Partly cloudy throughout the day with late afternoon rain.

2015
clear-day
44°/62°-
8

2014 Boulder Boulder

Becoming cloudy in the afternoon.

2014
clear-day
56°/72°-
8

2013 Boulder Boulder

Clear conditions throughout the day.

2013
clear-day
55°/80°-
8

2012 Boulder Boulder

Clear conditions throughout the day.

2012
clear-day
51°/71°-
8

2011 Boulder Boulder

Partly cloudy throughout the day.

2011
cloudy
55°/62°-
9

2010 Boulder Boulder

Partly cloudy throughout the day.

2010
partly-cloudy-day
46°/65°-
9

2009 Boulder Boulder

Partly cloudy throughout the day with rain.

2009
cloudy
43°/51°-
8

2008 Boulder Boulder

Cloudy skies throughout the day with a chance of rain throughout the day.

2008
cloudy
37°/41°Light
7

2006 Boulder Boulder

Partly cloudy throughout the day with late afternoon rain.

2006
partly-cloudy-day
38°/56°-
8

2005 Boulder Boulder

Cloudy skies throughout the day with rain.

2005
partly-cloudy-day
41°/48°Light
8

2004 Boulder Boulder

Partly cloudy throughout the day with morning rain or snow.

2004
partly-cloudy-day
34°/48°Light
6

2003 Boulder Boulder

Partly cloudy throughout the day with late afternoon rain.

2003
partly-cloudy-day
67°/87°-
8

2002 Boulder Boulder

Partly cloudy throughout the day.

2002
partly-cloudy-day
53°/79°-
9

2001 Boulder Boulder

Cloudy skies throughout the day with late afternoon rain.

2001
partly-cloudy-day
50°/76°-
8

2000 Boulder Boulder

Partly cloudy throughout the day.

2000
partly-cloudy-day
61°/87°-
7

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