Dubois, Idaho has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.6 °C (low) to 13.2 °C (high). Annual precipitation averages 286.8 Millimeters. Dubois is located in USDA Plant Hardiness Zone 5b. 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 | -12.8 °C | -2.6 °C | 19.3 mm |
| February | -11.1 °C | -0.2 °C | 14.73 mm |
| March | -6.1 °C | 6.4 °C | 18.03 mm |
| April | -1.8 °C | 13.4 °C | 26.92 mm |
| May | 2.7 °C | 18.6 °C | 50.55 mm |
| June | 6.4 °C | 23.7 °C | 44.2 mm |
| July | 10.1 °C | 29.7 °C | 14.48 mm |
| August | 9.3 °C | 29.2 °C | 13.46 mm |
| September | 4.6 °C | 23.2 °C | 23.11 mm |
| October | -1.2 °C | 14.2 °C | 24.89 mm |
| November | -7.1 °C | 5.1 °C | 15.49 mm |
| December | -11.9 °C | -1.9 °C | 21.59 mm |
| Annual | -1.6 °C | 13.2 °C | 286.75 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 21 - May 31 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |