Firestone, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 35 °F (low) to 65 °F (high). Annual precipitation averages 14.4 Inches. Firestone 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 | 15.3 °F | 43.7 °F | 0.39 in. |
| February | 17.7 °F | 45.6 °F | 0.43 in. |
| March | 26.1 °F | 56.0 °F | 1.23 in. |
| April | 33.1 °F | 62.3 °F | 1.79 in. |
| May | 42.8 °F | 71.1 °F | 2.4 in. |
| June | 51.9 °F | 83.4 °F | 1.45 in. |
| July | 57.7 °F | 89.6 °F | 1.43 in. |
| August | 55.3 °F | 87.3 °F | 1.64 in. |
| September | 46.7 °F | 79.5 °F | 1.49 in. |
| October | 34.3 °F | 65.8 °F | 1.04 in. |
| November | 23.9 °F | 52.9 °F | 0.72 in. |
| December | 15.4 °F | 43.1 °F | 0.43 in. |
| Annual | 35 °F | 65 °F | 14.44 in. |
| 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 : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |