Wellington, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 1.2 °C (low) to 16.9 °C (high). Annual precipitation averages 361.2 Millimeters. Wellington is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -9.2 °C | 5.7 °C | 7.37 mm |
| February | -8.4 °C | 6.3 °C | 8.13 mm |
| March | -4 °C | 11.8 °C | 22.1 mm |
| April | -0.2 °C | 15.3 °C | 42.42 mm |
| May | 5.3 °C | 20.1 °C | 73.91 mm |
| June | 10.4 °C | 26.6 °C | 49.02 mm |
| July | 13.5 °C | 30.2 °C | 39.88 mm |
| August | 12.2 °C | 28.8 °C | 34.8 mm |
| September | 7.6 °C | 24.6 °C | 32.77 mm |
| October | 0.9 °C | 17.2 °C | 28.7 mm |
| November | -4.9 °C | 10.3 °C | 13.46 mm |
| December | -9.1 °C | 5.3 °C | 8.64 mm |
| Annual | 1.2 °C | 16.9 °C | 361.2 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |