Lyons, Colorado has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 35.8 °F (low) to 64.3 °F (high). Annual precipitation averages 17.4 Inches. Lyons 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. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.2 °F | 44.7 °F | 0.55 in. |
| February | 19.5 °F | 45.6 °F | 0.62 in. |
| March | 26.9 °F | 54.8 °F | 1.37 in. |
| April | 33.0 °F | 61.1 °F | 2.07 in. |
| May | 42.1 °F | 69.7 °F | 3.19 in. |
| June | 51.0 °F | 81.9 °F | 2.22 in. |
| July | 57.2 °F | 88.0 °F | 1.62 in. |
| August | 55.0 °F | 85.7 °F | 1.62 in. |
| September | 47.2 °F | 78.0 °F | 1.79 in. |
| October | 35.8 °F | 64.9 °F | 1.14 in. |
| November | 26.0 °F | 52.7 °F | 0.76 in. |
| December | 18.2 °F | 44.0 °F | 0.46 in. |
| Annual | 35.8 °F | 64.3 °F | 17.41 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 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |