Arapahoe, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 2.8 °C (low) to 19.2 °C (high). Annual precipitation averages 429.8 Millimeters. Arapahoe is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.7 °C | 6.8 °C | 7.11 mm |
| February | -7.6 °C | 8.1 °C | 9.91 mm |
| March | -3.4 °C | 13.6 °C | 19.3 mm |
| April | 1 °C | 18.1 °C | 37.85 mm |
| May | 7.1 °C | 23.3 °C | 57.66 mm |
| June | 13 °C | 29.8 °C | 65.02 mm |
| July | 16.1 °C | 32.8 °C | 79.5 mm |
| August | 14.9 °C | 31.3 °C | 69.85 mm |
| September | 10.2 °C | 27.3 °C | 32.26 mm |
| October | 2.6 °C | 19.9 °C | 31.75 mm |
| November | -3.7 °C | 12.4 °C | 9.65 mm |
| December | -8.3 °C | 6.9 °C | 9.91 mm |
| Annual | 2.8 °C | 19.2 °C | 429.77 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |