Larkspur, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 33.1 °F (low) to 61.8 °F (high). Annual precipitation averages 20.4 Inches. Larkspur is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.9 °F | 43.4 °F | 0.71 in. |
| February | 17.3 °F | 44.0 °F | 0.76 in. |
| March | 23.8 °F | 51.8 °F | 1.78 in. |
| April | 29.8 °F | 57.8 °F | 2.48 in. |
| May | 38.8 °F | 67.0 °F | 2.65 in. |
| June | 47.9 °F | 78.6 °F | 2.0 in. |
| July | 54.0 °F | 84.2 °F | 2.59 in. |
| August | 52.5 °F | 82.0 °F | 2.7 in. |
| September | 44.5 °F | 75.3 °F | 1.73 in. |
| October | 33.1 °F | 63.3 °F | 1.23 in. |
| November | 23.3 °F | 51.4 °F | 0.93 in. |
| December | 16.0 °F | 43.1 °F | 0.79 in. |
| Annual | 33.1 °F | 61.8 °F | 20.35 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| 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 | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |