Buchanan, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 30.6 °F (low) to 51.6 °F (high). Annual precipitation averages 20.3 Inches. Buchanan is located in USDA Plant Hardiness Zone 4b. 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 | 0.6 °F | 18.3 °F | 0.47 in. |
| February | 4.4 °F | 23.0 °F | 0.46 in. |
| March | 16.1 °F | 35.4 °F | 0.75 in. |
| April | 29.6 °F | 52.4 °F | 1.07 in. |
| May | 42.6 °F | 66.1 °F | 2.92 in. |
| June | 53.9 °F | 75.5 °F | 3.52 in. |
| July | 58.2 °F | 80.7 °F | 3.67 in. |
| August | 55.3 °F | 80.0 °F | 2.35 in. |
| September | 46.0 °F | 71.1 °F | 2.21 in. |
| October | 33.2 °F | 55.2 °F | 1.67 in. |
| November | 19.3 °F | 37.6 °F | 0.62 in. |
| December | 7.4 °F | 23.7 °F | 0.63 in. |
| Annual | 30.6 °F | 51.6 °F | 20.34 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 4b : -25°F to -20°F |
| Plant Hardiness Zone - 2012 | Zone 4a : -30°F to -25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |