Decatur, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 38 °F (low) to 60.8 °F (high). Annual precipitation averages 31.1 Inches. Decatur is located in USDA Plant Hardiness Zone 5a. 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 | 10.9 °F | 30.5 °F | 0.66 in. |
| February | 15.0 °F | 35.2 °F | 0.85 in. |
| March | 25.9 °F | 48.8 °F | 1.64 in. |
| April | 37.0 °F | 62.2 °F | 3.45 in. |
| May | 49.3 °F | 73.0 °F | 4.44 in. |
| June | 60.2 °F | 82.8 °F | 4.68 in. |
| July | 63.9 °F | 86.0 °F | 3.55 in. |
| August | 61.2 °F | 83.9 °F | 3.96 in. |
| September | 51.9 °F | 77.9 °F | 3.15 in. |
| October | 39.1 °F | 65.1 °F | 2.25 in. |
| November | 26.2 °F | 48.7 °F | 1.39 in. |
| December | 15.9 °F | 35.0 °F | 1.07 in. |
| Annual | 38 °F | 60.8 °F | 31.09 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 5a : -20°F to -15°F |
| Plant Hardiness Zone - 2012 | Zone 5a : -20°F to -15°F |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |