Bonanza, Colorado has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -3.7 °C (low) to 11.3 °C (high). Annual precipitation averages 545.6 Millimeters. Bonanza is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Aug. 21 - Aug. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.9 °C | 0.4 °C | 37.85 mm |
| February | -11.8 °C | 1.6 °C | 49.02 mm |
| March | -8.4 °C | 5.7 °C | 48.01 mm |
| April | -5.1 °C | 9.5 °C | 66.04 mm |
| May | -0.7 °C | 14.7 °C | 50.55 mm |
| June | 3.6 °C | 21.3 °C | 25.91 mm |
| July | 6.7 °C | 23.5 °C | 59.94 mm |
| August | 5.8 °C | 22.2 °C | 56.9 mm |
| September | 2.4 °C | 18.7 °C | 35.81 mm |
| October | -2.3 °C | 12.4 °C | 42.16 mm |
| November | -8.4 °C | 5.3 °C | 32.77 mm |
| December | -12.7 °C | 0.3 °C | 40.64 mm |
| Annual | -3.7 °C | 11.3 °C | 545.6 mm |
| Average First Frost Date | Aug. 21 - Aug. 31 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 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 | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |