Leonard, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 31.5 °F (low) to 52.2 °F (high). Annual precipitation averages 23.7 Inches. Leonard 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 | 0.0 °F | 18.0 °F | 0.6 in. |
| February | 4.0 °F | 23.2 °F | 0.6 in. |
| March | 17.0 °F | 35.9 °F | 0.98 in. |
| April | 31.2 °F | 53.2 °F | 1.38 in. |
| May | 44.5 °F | 67.4 °F | 3.1 in. |
| June | 55.8 °F | 76.9 °F | 4.34 in. |
| July | 59.3 °F | 81.2 °F | 3.37 in. |
| August | 56.4 °F | 80.0 °F | 2.74 in. |
| September | 47.1 °F | 71.7 °F | 2.78 in. |
| October | 34.5 °F | 56.2 °F | 2.26 in. |
| November | 20.3 °F | 38.8 °F | 0.77 in. |
| December | 7.9 °F | 24.3 °F | 0.73 in. |
| Annual | 31.5 °F | 52.2 °F | 23.65 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 | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |