Fort Hall, Idaho has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 0.5 °C (low) to 15.3 °C (high). Annual precipitation averages 264.9 Millimeters. Fort Hall is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 21 - May 31 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.8 °C | 0.5 °C | 22.61 mm |
| February | -7.2 °C | 3.2 °C | 17.78 mm |
| March | -2.9 °C | 9.6 °C | 25.91 mm |
| April | -0.2 °C | 14.5 °C | 26.92 mm |
| May | 4 °C | 19.7 °C | 36.07 mm |
| June | 7.6 °C | 24.8 °C | 25.15 mm |
| July | 10.7 °C | 30.8 °C | 9.91 mm |
| August | 9.9 °C | 30.4 °C | 12.95 mm |
| September | 5.7 °C | 24.7 °C | 21.59 mm |
| October | 0.3 °C | 16.3 °C | 23.88 mm |
| November | -4.6 °C | 7.6 °C | 19.3 mm |
| December | -8.7 °C | 0.9 °C | 22.86 mm |
| Annual | 0.5 °C | 15.3 °C | 264.93 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |