Voltaire, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 29.2 °F (low) to 51.9 °F (high). Annual precipitation averages 19.4 Inches. Voltaire is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -0.4 °F | 18.9 °F | 0.58 in. |
| February | 3.1 °F | 23.6 °F | 0.51 in. |
| March | 15.3 °F | 35.7 °F | 0.7 in. |
| April | 28.3 °F | 53.4 °F | 1.07 in. |
| May | 41.5 °F | 66.7 °F | 2.85 in. |
| June | 52.4 °F | 75.0 °F | 3.82 in. |
| July | 57.0 °F | 80.6 °F | 2.92 in. |
| August | 54.0 °F | 80.9 °F | 2.1 in. |
| September | 44.6 °F | 71.6 °F | 1.74 in. |
| October | 31.6 °F | 55.5 °F | 1.53 in. |
| November | 17.7 °F | 37.3 °F | 0.91 in. |
| December | 5.5 °F | 23.9 °F | 0.67 in. |
| Annual | 29.2 °F | 51.9 °F | 19.4 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |