Franktown, Colorado has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 1.5 °C (low) to 17.6 °C (high). Annual precipitation averages 465.3 Millimeters. 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 | -8.3 °C | 7.1 °C | 15.24 mm |
| February | -7.6 °C | 7.5 °C | 15.49 mm |
| March | -3.6 °C | 12.1 °C | 36.07 mm |
| April | -0.3 °C | 15.4 °C | 55.12 mm |
| May | 4.8 °C | 20.3 °C | 58.67 mm |
| June | 10.1 °C | 26.9 °C | 53.85 mm |
| July | 13.4 °C | 30.3 °C | 57.4 mm |
| August | 12.6 °C | 29 °C | 74.68 mm |
| September | 8.1 °C | 25.2 °C | 35.05 mm |
| October | 1.4 °C | 18.2 °C | 28.7 mm |
| November | -3.8 °C | 11.8 °C | 19.81 mm |
| December | -8.3 °C | 6.8 °C | 15.24 mm |
| Annual | 1.5 °C | 17.6 °C | 465.32 mm |
| 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 : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |