Arthur, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31 °F (low) to 51.9 °F (high). Annual precipitation averages 23.3 Inches. Arthur 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 Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -1.3 °F | 16.6 °F | 0.53 in. |
| February | 3.0 °F | 22.1 °F | 0.53 in. |
| March | 16.5 °F | 34.6 °F | 0.94 in. |
| April | 30.9 °F | 53.5 °F | 1.26 in. |
| May | 44.0 °F | 68.1 °F | 3.09 in. |
| June | 55.2 °F | 77.1 °F | 4.03 in. |
| July | 58.8 °F | 81.2 °F | 3.68 in. |
| August | 55.9 °F | 80.5 °F | 2.71 in. |
| September | 47.0 °F | 72.1 °F | 2.84 in. |
| October | 34.6 °F | 56.2 °F | 2.19 in. |
| November | 20.1 °F | 38.0 °F | 0.75 in. |
| December | 7.0 °F | 23.1 °F | 0.76 in. |
| Annual | 31 °F | 51.9 °F | 23.31 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4a : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |