Waterloo, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.6 °C (low) to 16.4 °C (high). Annual precipitation averages 825 Millimeters. Waterloo 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.1 °C | 0.3 °C | 20.07 mm |
| February | -7.9 °C | 3.1 °C | 27.69 mm |
| March | -2.1 °C | 10.1 °C | 43.94 mm |
| April | 3.9 °C | 16.9 °C | 81.03 mm |
| May | 10.5 °C | 22.5 °C | 122.94 mm |
| June | 16.6 °C | 28.2 °C | 125.98 mm |
| July | 18.8 °C | 30.2 °C | 88.9 mm |
| August | 17.4 °C | 29.1 °C | 101.6 mm |
| September | 12.2 °C | 25.6 °C | 81.03 mm |
| October | 5.2 °C | 18.4 °C | 62.99 mm |
| November | -1.9 °C | 9.8 °C | 35.56 mm |
| December | -7.4 °C | 2.6 °C | 33.27 mm |
| Annual | 4.6 °C | 16.4 °C | 825 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |