BOLDERBoulder

Boulder, CO, USA · May 31, 2027
partly-cloudy-day52°·52° high·Light·Dry
10
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Race Day Weather

partly-cloudy-day
52°at start
76° high
Light
Dry
Your goal
0:00:00

Cool start, warming trend ahead

Runners will face a temperature rising from 50°F at the start to a warm 73°F by the finish. With light winds from the S, conditions are generally favorable, and humidity will remain moderate at 49%. To maintain performance, runners should start conservatively and hydrate frequently as temperatures increase.

Race day forecast available in 207 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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FAQ

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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
49°F
L:47° H:50°
RunScore
10
Conditions
Rain Freq
0%
0 of 26 yrs
Wind4mph
Dew40°F

Temperature History

Range of temperatures during race hours for each year.

Detailed History

YearConditionsLow / HighRainScore

2026 BOLDERBoulder

Clear conditions throughout the day.

2026
clear-day
53°/59°-
10

2025 BOLDERBoulder

Partly cloudy throughout the day with rain.

2025
fog
48°/50°-
10

2024 BOLDERBoulder

Clear conditions throughout the day.

2024
clear-day
52°/55°-
10

2023 BOLDERBoulder

Clear conditions throughout the day.

2023
clear-day
50°/54°-
10

2022 BOLDERBoulder

Clearing in the afternoon with early morning rain.

2022
partly-cloudy-day
46°/50°-
10

2021 BOLDERBoulder

Becoming cloudy in the afternoon with late afternoon rain.

2021
clear-day
51°/53°-
10

2020 BOLDERBoulder

Clear conditions throughout the day.

2020
clear-day
47°/52°-
10

2019 BOLDERBoulder

Partly cloudy throughout the day with rain.

2019
partly-cloudy-day
42°/43°-
10

2018 BOLDERBoulder

Partly cloudy throughout the day with afternoon rain.

2018
cloudy
59°/59°-
8

2017 BOLDERBoulder

Becoming cloudy in the afternoon with rain.

2017
clear-day
48°/50°-
10

2016 BOLDERBoulder

Clear conditions throughout the day with afternoon rain.

2016
clear-day
46°/52°-
10

2015 BOLDERBoulder

Partly cloudy throughout the day with late afternoon rain.

2015
partly-cloudy-day
41°/44°-
10

2014 BOLDERBoulder

Becoming cloudy in the afternoon.

2014
clear-day
54°/56°-
10

2013 BOLDERBoulder

Clear conditions throughout the day.

2013
clear-day
51°/55°-
10

2012 BOLDERBoulder

Clear conditions throughout the day.

2012
clear-day
46°/51°-
10

2011 BOLDERBoulder

Partly cloudy throughout the day.

2011
cloudy
55°/55°-
8

2010 BOLDERBoulder

Partly cloudy throughout the day.

2010
partly-cloudy-day
41°/46°-
10

2009 BOLDERBoulder

Partly cloudy throughout the day with rain.

2009
cloudy
42°/43°-
10

2008 BOLDERBoulder

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

2008
partly-cloudy-day
39°/41°-
10

2006 BOLDERBoulder

Partly cloudy throughout the day with late afternoon rain.

2006
partly-cloudy-day
35°/38°-
10

2005 BOLDERBoulder

Cloudy skies throughout the day with rain.

2005
partly-cloudy-day
36°/41°-
10

2004 BOLDERBoulder

Partly cloudy throughout the day with morning rain or snow.

2004
partly-cloudy-day
32°/34°-
10

2003 BOLDERBoulder

Partly cloudy throughout the day with late afternoon rain.

2003
partly-cloudy-day
63°/67°-
7

2002 BOLDERBoulder

Partly cloudy throughout the day.

2002
partly-cloudy-day
48°/53°-
10

2001 BOLDERBoulder

Cloudy skies throughout the day with late afternoon rain.

2001
partly-cloudy-day
48°/50°-
10

2000 BOLDERBoulder

Partly cloudy throughout the day.

2000
partly-cloudy-day
61°/61°-
8

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Free guidesRace Morning Guide·Race Day Gear Guide·Pacing Strategy Guide

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