Palermo, North Dakota has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 28.1 °F (low) to 50.1 °F (high). Annual precipitation averages 18.1 Inches. Palermo 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 | -0.5 °F | 17.8 °F | 0.52 in. |
| February | 3.5 °F | 22.3 °F | 0.49 in. |
| March | 14.8 °F | 34.4 °F | 0.68 in. |
| April | 27.4 °F | 51.7 °F | 1.03 in. |
| May | 39.4 °F | 64.0 °F | 2.65 in. |
| June | 50.0 °F | 72.3 °F | 3.92 in. |
| July | 54.4 °F | 78.7 °F | 2.88 in. |
| August | 52.2 °F | 79.5 °F | 1.84 in. |
| September | 42.5 °F | 69.6 °F | 1.49 in. |
| October | 30.4 °F | 53.1 °F | 1.31 in. |
| November | 17.0 °F | 35.7 °F | 0.67 in. |
| December | 5.5 °F | 22.3 °F | 0.61 in. |
| Annual | 28.1 °F | 50.1 °F | 18.09 in. |
| 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 : -30°F to -25°F |
| Plant Hardiness Zone - 2012 | Zone 3b : -35°F to -30°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |