Spiritwood, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -0.8 °C (low) to 10.9 °C (high). Annual precipitation averages 541.3 Millimeters. Spiritwood 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 Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -17.7 °C | -7.7 °C | 12.45 mm |
| February | -15.6 °C | -4.9 °C | 12.19 mm |
| March | -8.8 °C | 1.9 °C | 20.83 mm |
| April | -1.3 °C | 11.3 °C | 32.51 mm |
| May | 6.1 °C | 19.1 °C | 78.49 mm |
| June | 12.3 °C | 24.4 °C | 93.73 mm |
| July | 14.7 °C | 27.3 °C | 89.92 mm |
| August | 13.1 °C | 26.7 °C | 62.48 mm |
| September | 7.9 °C | 21.7 °C | 60.71 mm |
| October | 0.6 °C | 12.8 °C | 45.21 mm |
| November | -7.1 °C | 3.2 °C | 16.26 mm |
| December | -13.7 °C | -4.6 °C | 16.51 mm |
| Annual | -0.8 °C | 10.9 °C | 541.29 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -34.4°C to -31.7°C |
| Plant Hardiness Zone - 2012 | Zone 4a : -34.4°C to -31.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |