Boulder Weather, When to Go and Climate Information

(Boulder, Colorado - CO, USA)

The climate of Boulder is noticeably dry all through the year and is the summer months, the plentiful sunny weather means that temperatures can quickly soar on the hottest of days. Very typical of Boulder is a fine start to the day, with blue skies slowly cloudy over later in the day.

Contrasting greatly with the warm daytime climate are the nights, which are noticeably cooler and often feel rather chilly, so if you are out and about in the evening, you will likely need a pullover or jacket. July tends to experience the hottest weather in Boulder and the mildest evenings, with summer highs of 31°C / 88°F, dropping to 15°C / 59°F by night.

Panoramic photo of Folsom Field

Seasonal Climate Variations / When to Go

Located at the base of the Flagstaff Mountain and on the eastern side of the continental divide, the climate of Boulder can at times be quite desert-like, with more than 300 days on sunshine every single year. The proximity of the mountains tends to provide some shelter during the winter months, protecting the city from the most severe storms.

Winters in Boulder are usually very white and snowy weather is quite predictable, with the average winter snowfall generally exceeding 200 cm / 79 inches. The winter climate tends to be considerably milder than many other parts of Colorado and the snowfalls soon melts. By March, spring is well on its way and frosty nights quickly become a thing of the past.

Boulder Weather and Climate Chart (Averages)



6°C / 43°F
-6°C / 21°F


8°C / 46°F
-4°C / 25°F


11°C / 52°F
-3°C / 27°F


17°C / 63°F
2°C / 36°F


22°C / 72°F
6°C / 43°F


27°C / 81°F
12°C / 54°F


31°C / 88°F
15°C / 59°F


30°C / 86°F
14°C / 57°F


25°C / 77°F
9°C / 48°F


19°C / 66°F
3°C / 37°F


11°C / 52°F
-3°C / 27°F


7°C / 45°F
-7°C / 19°F