BOLDERBoulder

Boulder, CO, USA · May 31, 2027

52°·72° high·Light·Dry

Weather

Race Day Weather

52°at start

76° high

Light

Dry

Cool start, warming trend ahead

Runners will face a temperature rise from 50°F at the start to a peak of 73°F. With light wind from the S, humidity will remain moderate at 49%. As temperatures increase, runners should consider adjusting their pace and hydrating frequently to maintain performance.

Race day forecast available in 253 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

Website

Course Map

FAQ

When is the 2027 BOLDERBoulder?

The 2027 BOLDERBoulder will be held on Monday May 31, 2027.

What will the weather be like for the 2027 BOLDERBoulder?

The forecast calls for a high of 79°F and a low of 51°F with a 7% chance of rain.

Historical Weather

Based on 26 years of data

Avg Temp

67°F

L:50° H:67°

RunScore

Conditions

Rain Freq

12%

3 of 26 yrs

Wind8mph

Dew38°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

Year	Low / High	Rain	Dew Point
2026 BOLDERBoulder Clear conditions throughout the day. 2026	59°/80°	-	38°
2025 BOLDERBoulder Partly cloudy throughout the day with rain. 2025	50°/61°	-	51°
2024 BOLDERBoulder Clear conditions throughout the day. 2024	55°/74°	-	34°
2023 BOLDERBoulder Clear conditions throughout the day. 2023	54°/77°	-	45°
2022 BOLDERBoulder Clearing in the afternoon with early morning rain. 2022	50°/62°	-	29°
2021 BOLDERBoulder Becoming cloudy in the afternoon with late afternoon rain. 2021	53°/63°	-	48°
2020 BOLDERBoulder Clear conditions throughout the day. 2020	52°/77°	-	30°
2019 BOLDERBoulder Partly cloudy throughout the day with rain. 2019	42°/56°	-	41°
2018 BOLDERBoulder Partly cloudy throughout the day with afternoon rain. 2018	59°/64°	-	51°
2017 BOLDERBoulder Becoming cloudy in the afternoon with rain. 2017	50°/67°	-	41°
2016 BOLDERBoulder Clear conditions throughout the day with afternoon rain. 2016	52°/77°	-	38°
2015 BOLDERBoulder Partly cloudy throughout the day with late afternoon rain. 2015	44°/62°	-	42°
2014 BOLDERBoulder Becoming cloudy in the afternoon. 2014	56°/72°	-	43°
2013 BOLDERBoulder Clear conditions throughout the day. 2013	55°/80°	-	24°
2012 BOLDERBoulder Clear conditions throughout the day. 2012	51°/71°	-	17°
2011 BOLDERBoulder Partly cloudy throughout the day. 2011	55°/62°	-	50°
2010 BOLDERBoulder Partly cloudy throughout the day. 2010	46°/65°	-	38°
2009 BOLDERBoulder Partly cloudy throughout the day with rain. 2009	43°/51°	-	51°
2008 BOLDERBoulder Cloudy skies throughout the day with a chance of rain throughout the day. 2008	37°/41°	Light	45°
2006 BOLDERBoulder Partly cloudy throughout the day with late afternoon rain. 2006	38°/56°	-	29°
2005 BOLDERBoulder Cloudy skies throughout the day with rain. 2005	41°/48°	Light	52°
2004 BOLDERBoulder Partly cloudy throughout the day with morning rain or snow. 2004	34°/48°	Light	26°
2003 BOLDERBoulder Partly cloudy throughout the day with late afternoon rain. 2003	67°/87°	-	47°
2002 BOLDERBoulder Partly cloudy throughout the day. 2002	53°/79°	-	37°
2001 BOLDERBoulder Cloudy skies throughout the day with late afternoon rain. 2001	50°/76°	-	45°
2000 BOLDERBoulder Partly cloudy throughout the day. 2000	61°/87°	-	47°

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