Garrison, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.8 °C (low) to 16.3 °C (high). Annual precipitation averages 751.6 Millimeters. Garrison is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.6 °C | 0.5 °C | 17.27 mm |
| February | -8.6 °C | 3.1 °C | 20.83 mm |
| March | -2.9 °C | 10 °C | 39.62 mm |
| April | 2.9 °C | 16.6 °C | 74.17 mm |
| May | 9.7 °C | 22.6 °C | 121.16 mm |
| June | 15.7 °C | 27.9 °C | 119.13 mm |
| July | 18.1 °C | 30.1 °C | 81.03 mm |
| August | 16.7 °C | 28.9 °C | 98.04 mm |
| September | 11.6 °C | 25.6 °C | 67.56 mm |
| October | 4.4 °C | 18.3 °C | 54.86 mm |
| November | -2.8 °C | 9.7 °C | 32.77 mm |
| December | -8.4 °C | 2.4 °C | 25.15 mm |
| Annual | 3.8 °C | 16.3 °C | 751.59 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |