Hayden, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 2.2 °C (low) to 14.3 °C (high). Annual precipitation averages 649.7 Millimeters. Hayden is located in USDA Plant Hardiness Zone 6b. 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 | -4.3 °C | 2 °C | 87.12 mm |
| February | -4.3 °C | 4.3 °C | 54.61 mm |
| March | -2 °C | 8.9 °C | 65.79 mm |
| April | 0.9 °C | 13.5 °C | 53.09 mm |
| May | 5 °C | 18.9 °C | 53.59 mm |
| June | 8.2 °C | 22.2 °C | 45.72 mm |
| July | 10.9 °C | 28.2 °C | 18.29 mm |
| August | 10.5 °C | 28.5 °C | 16.76 mm |
| September | 6.3 °C | 22.9 °C | 21.08 mm |
| October | 1.8 °C | 14.3 °C | 58.42 mm |
| November | -1.6 °C | 6.3 °C | 81.79 mm |
| December | -4.5 °C | 1.5 °C | 93.47 mm |
| Annual | 2.2 °C | 14.3 °C | 649.73 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 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |