The year gets off to a chilly start with January's temperatures ranging from 8°F (-13°C) to 35°F (2°C) and annual snowfall averaging up to 15ft (4.6m), although that figure jumps to up to 25ft (7.6m) around the ski resorts. It's not unheard of to see snow as late as June and as early as September in Aspen, and summer isn't any more predictable, with thunderstorms randomly punctuating otherwise pleasant summer days. July and August can reach temperatures of 75-80°F (23-26°C), but nights are cold.
| Month | Temp (°C) | Rainfall (mm) | Humidity (%) | Sunshine (hours) |
| Jan | -14 - 1 | 40 | ||
| Feb | -13 - 2 | 54 | ||
| Mar | -9 - 6 | 72 | ||
| Apr | -3 - 11 | 65 | ||
| May | 0 - 17 | 56 | ||
| Jun | 3 - 23 | 36 | ||
| Jul | 6 - 26 | 45 | ||
| Aug | 6 - 25 | 40 | ||
| Sep | 2 - 21 | 51 | ||
| Oct | -2 - 15 | 49 | ||
| Nov | -8 - 7 | 65 | ||
| Dec | -12 - 2 | 46 |