Arnegard, North Dakota has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from -1.1 °C (low) to 12.1 °C (high). Annual precipitation averages 413.8 Millimeters. Arnegard 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.11 - Sep. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -15.9 °C | -5.2 °C | 11.43 mm |
| February | -13.7 °C | -2.4 °C | 9.14 mm |
| March | -8 °C | 4.2 °C | 14.48 mm |
| April | -1.6 °C | 12.5 °C | 25.4 mm |
| May | 4.6 °C | 18.8 °C | 62.23 mm |
| June | 10.2 °C | 23.7 °C | 82.3 mm |
| July | 13.1 °C | 28.3 °C | 69.09 mm |
| August | 12.1 °C | 28.2 °C | 42.16 mm |
| September | 6.6 °C | 22.4 °C | 40.39 mm |
| October | -0.2 °C | 13.2 °C | 28.7 mm |
| November | -7.3 °C | 4.1 °C | 15.24 mm |
| December | -13.2 °C | -2.8 °C | 13.21 mm |
| Annual | -1.1 °C | 12.1 °C | 413.77 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |