Viola, Idaho has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 2.5 °C (low) to 14.3 °C (high). Annual precipitation averages 639.6 Millimeters. Viola is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.4 °C | 2.5 °C | 88.9 mm |
| February | -2.9 °C | 4.7 °C | 61.98 mm |
| March | -0.8 °C | 8.8 °C | 67.82 mm |
| April | 1.7 °C | 13.1 °C | 58.42 mm |
| May | 5 °C | 18.2 °C | 55.88 mm |
| June | 7.4 °C | 21.4 °C | 37.08 mm |
| July | 9.2 °C | 27.9 °C | 12.45 mm |
| August | 9.3 °C | 28.7 °C | 15.75 mm |
| September | 6.2 °C | 23.3 °C | 20.32 mm |
| October | 2.4 °C | 14.9 °C | 53.59 mm |
| November | -0.8 °C | 6.7 °C | 76.2 mm |
| December | -3.8 °C | 1.9 °C | 91.19 mm |
| Annual | 2.5 °C | 14.3 °C | 639.58 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Severe Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |