Hayden, Colorado has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2.1 °C (low) to 14.1 °C (high). Annual precipitation averages 465.8 Millimeters. Hayden is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Jun. 1 - Jun. 10 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -13.9 °C | -1.1 °C | 46.99 mm |
| February | -11.6 °C | 1.4 °C | 36.58 mm |
| March | -6.3 °C | 7.7 °C | 34.29 mm |
| April | -2.2 °C | 13.1 °C | 52.83 mm |
| May | 2.2 °C | 18.8 °C | 48.01 mm |
| June | 5.9 °C | 25.4 °C | 27.43 mm |
| July | 9.8 °C | 29.5 °C | 27.18 mm |
| August | 8.9 °C | 28.3 °C | 32.51 mm |
| September | 4.2 °C | 23.6 °C | 41.66 mm |
| October | -1.7 °C | 15.8 °C | 38.86 mm |
| November | -7.1 °C | 7.3 °C | 38.1 mm |
| December | -12.9 °C | -0.2 °C | 41.4 mm |
| Annual | -2.1 °C | 14.1 °C | 465.84 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | Jun. 1 - Jun. 10 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |