Milnor, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Annual precipitation averages 601.7 Millimeters. Milnor is located in USDA Plant Hardiness Zone 4a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -17.3 °C | -7.3 °C | 16 mm |
| February | -15.1 °C | -4.7 °C | 15.49 mm |
| March | -8 °C | 2.4 °C | 24.89 mm |
| April | -0.2 °C | 11.8 °C | 43.43 mm |
| May | 7.2 °C | 19.7 °C | 78.49 mm |
| June | 13.4 °C | 24.9 °C | 108.2 mm |
| July | 15.4 °C | 27.5 °C | 88.14 mm |
| August | 13.9 °C | 26.7 °C | 64.01 mm |
| September | 8.7 °C | 22.3 °C | 67.31 mm |
| October | 1.4 °C | 13.6 °C | 57.66 mm |
| November | -6.2 °C | 3.8 °C | 19.56 mm |
| December | -13.2 °C | -3.9 °C | 18.54 mm |
| Annual | 0 °C | 11.4 °C | 601.72 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |