Donnybrook, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from -1.6 °C (low) to 10.5 °C (high). Annual precipitation averages 458.5 Millimeters. Donnybrook is located in USDA Plant Hardiness Zone 4a. 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 | -17.8 °C | -7.8 °C | 13.21 mm |
| February | -15.6 °C | -5.2 °C | 12.45 mm |
| March | -9.3 °C | 1.4 °C | 16.76 mm |
| April | -2.2 °C | 11.1 °C | 26.92 mm |
| May | 5.1 °C | 18.5 °C | 66.8 mm |
| June | 11.1 °C | 23.2 °C | 96.77 mm |
| July | 13.2 °C | 26.6 °C | 71.37 mm |
| August | 11.9 °C | 27.1 °C | 50.04 mm |
| September | 6.7 °C | 21.4 °C | 39.88 mm |
| October | -0.3 °C | 12.2 °C | 36.07 mm |
| November | -7.9 °C | 2.2 °C | 14.22 mm |
| December | -14.6 °C | -5.1 °C | 13.97 mm |
| Annual | -1.6 °C | 10.5 °C | 458.46 mm |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 11 - May 20 |
| 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 |