Franktown, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 34.8 °F (low) to 63.6 °F (high). Annual precipitation averages 18.3 Inches. Franktown 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.0 °F | 44.8 °F | 0.6 in. |
| February | 18.3 °F | 45.5 °F | 0.61 in. |
| March | 25.5 °F | 53.7 °F | 1.42 in. |
| April | 31.5 °F | 59.8 °F | 2.17 in. |
| May | 40.7 °F | 68.6 °F | 2.31 in. |
| June | 50.2 °F | 80.5 °F | 2.12 in. |
| July | 56.2 °F | 86.6 °F | 2.26 in. |
| August | 54.7 °F | 84.2 °F | 2.94 in. |
| September | 46.5 °F | 77.4 °F | 1.38 in. |
| October | 34.5 °F | 64.8 °F | 1.13 in. |
| November | 25.1 °F | 53.2 °F | 0.78 in. |
| December | 17.0 °F | 44.3 °F | 0.6 in. |
| Annual | 34.8 °F | 63.6 °F | 18.32 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |