Cottonwood, Idaho has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 34.5 °F (low) to 57.1 °F (high). Annual precipitation averages 21.5 Inches. Cottonwood is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 22.5 °F | 36.4 °F | 1.81 in. |
| February | 23.7 °F | 40.5 °F | 1.47 in. |
| March | 27.6 °F | 46.9 °F | 1.77 in. |
| April | 32.3 °F | 54.5 °F | 2.19 in. |
| May | 38.9 °F | 63.0 °F | 2.83 in. |
| June | 44.0 °F | 69.6 °F | 2.66 in. |
| July | 49.8 °F | 81.1 °F | 1.1 in. |
| August | 49.7 °F | 82.8 °F | 0.9 in. |
| September | 42.7 °F | 72.5 °F | 1.03 in. |
| October | 34.3 °F | 58.2 °F | 1.7 in. |
| November | 27.2 °F | 43.4 °F | 2.05 in. |
| December | 21.6 °F | 35.7 °F | 1.98 in. |
| Annual | 34.5 °F | 57.1 °F | 21.49 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |