Calvin, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -2.8 °C (low) to 8.6 °C (high). Annual precipitation averages 518.4 Millimeters. Calvin is located in USDA Plant Hardiness Zone 3b. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Sep.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -20.5 °C | -10.6 °C | 15.49 mm |
| February | -18.7 °C | -7.9 °C | 15.49 mm |
| March | -11.2 °C | -1.2 °C | 20.07 mm |
| April | -2.7 °C | 9.1 °C | 25.4 mm |
| May | 4.4 °C | 17.4 °C | 65.53 mm |
| June | 10.7 °C | 22.6 °C | 96.27 mm |
| July | 12.7 °C | 25.1 °C | 82.04 mm |
| August | 11.4 °C | 25.1 °C | 68.07 mm |
| September | 6.3 °C | 19.9 °C | 50.04 mm |
| October | -0.8 °C | 10.8 °C | 38.35 mm |
| November | -9 °C | 0.4 °C | 22.1 mm |
| December | -16.6 °C | -7.6 °C | 19.56 mm |
| Annual | -2.8 °C | 8.6 °C | 518.41 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 3b : -37.2°C to -34.4°C |
| Plant Hardiness Zone - 2012 | Zone 3b : -37.2°C to -34.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |