Kootenai, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 1.7 °C (low) to 13.7 °C (high). Annual precipitation averages 821.7 Millimeters. Kootenai is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.9 °C | 1.2 °C | 112.01 mm |
| February | -4.7 °C | 3.6 °C | 70.61 mm |
| March | -2.3 °C | 8.1 °C | 87.88 mm |
| April | 0.8 °C | 13.2 °C | 60.2 mm |
| May | 4.7 °C | 18.9 °C | 60.45 mm |
| June | 7.7 °C | 22.1 °C | 61.98 mm |
| July | 10 °C | 27.7 °C | 28.7 mm |
| August | 9.3 °C | 27.8 °C | 21.84 mm |
| September | 5.3 °C | 21.9 °C | 32.26 mm |
| October | 1.2 °C | 13.4 °C | 68.83 mm |
| November | -1.9 °C | 5.4 °C | 102.87 mm |
| December | -5 °C | 0.9 °C | 114.05 mm |
| Annual | 1.7 °C | 13.7 °C | 821.68 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |