Climate normals · 1970–2000
Boulder Climate
Boulder is a city in United States (CO) with a population of about 106,803. Its average annual temperature is 9.2°C (49°F), with roughly 465 mm of rain per year.
9.2°C
Avg Temp
465
Precip (mm/yr)
Jul
Hottest Month
Jan
Coldest Month
Boulder Climate
Boulder has an average annual temperature of 9.2°C (49°F) and receives about 465 mm of precipitation per year. The warmest month is July and the coldest is January. Figures are 1970–2000 climate normals.
9.2°C
Avg Temp
465
Precip (mm/yr)
Jul
Hottest Month
Jan
Coldest Month
| Month | Avg (°C/°F) | Precip |
|---|---|---|
| January | -1° / 30° | 16 mm |
| February | 0° / 33° | 18 mm |
| March | 4° / 38° | 42 mm |
| April | 7° / 45° | 59 mm |
| May | 13° / 55° | 69 mm |
| June | 18° / 64° | 49 mm |
| July | 21° / 70° | 49 mm |
| August | 20° / 69° | 42 mm |
| September | 16° / 60° | 40 mm |
| October | 10° / 49° | 31 mm |
| November | 3° / 37° | 31 mm |
| December | 0° / 32° | 19 mm |
1970–2000 normals from WorldClim 2.1 (~9 km grid). Precipitation can be less precise near mountains or coastlines, where rainfall varies sharply over short distances.
Best time to visit Boulder
The most comfortable months to visit Boulder are typically July, August and June, when temperatures are mildest and rainfall is relatively low. The hottest month is July (around 30°C high). The coldest is January (near -9°C low). May is usually the wettest month.
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Frequently Asked Questions
The most comfortable months to visit Boulder are typically July, August and June, when temperatures are mildest and rainfall is relatively low (1970–2000 climate normals).
Boulder, United States has an average annual temperature of 9.2°C and about 465 mm of precipitation per year. The warmest month is July and the coldest is January.
In July, the hottest month, daily highs in Boulder average about 30°C (86°F).
Monthly climate normals (1970–2000) sampled from WorldClim 2.1 at ~9 km resolution. Humidity derived from vapor pressure. City coordinates and population from GeoNames.