Harrison, Nebraska has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 0.1 °C (low) to 14.6 °C (high). Annual precipitation averages 446 Millimeters. Harrison is located in USDA Plant Hardiness Zone 5a. 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 | -10.5 °C | 2.1 °C | 9.14 mm |
| February | -9.4 °C | 2.9 °C | 11.43 mm |
| March | -5.4 °C | 8.6 °C | 26.16 mm |
| April | -1.7 °C | 12.4 °C | 56.39 mm |
| May | 3.9 °C | 17.8 °C | 92.46 mm |
| June | 9.4 °C | 24.4 °C | 71.63 mm |
| July | 13.1 °C | 29.3 °C | 47.5 mm |
| August | 12 °C | 28.8 °C | 34.54 mm |
| September | 6.7 °C | 23.5 °C | 34.54 mm |
| October | -0.2 °C | 14.8 °C | 37.34 mm |
| November | -6.2 °C | 7.7 °C | 13.97 mm |
| December | -10.4 °C | 2.3 °C | 10.92 mm |
| Annual | 0.1 °C | 14.6 °C | 446.02 mm |
| Average First Frost Date | Sep.11 - Sep. 20 |
| Average Last Frost Date | May 11 - May 20 |
| Average Days With Frost | Over 180 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |