De Witt, Nebraska has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.9 °F (low) to 63.4 °F (high). Annual precipitation averages 30.8 Inches. De Witt is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 15.5 °F | 35.4 °F | 0.73 in. |
| February | 19.6 °F | 40.2 °F | 0.9 in. |
| March | 29.1 °F | 52.1 °F | 1.67 in. |
| April | 39.6 °F | 63.4 °F | 2.82 in. |
| May | 51.0 °F | 73.9 °F | 5.13 in. |
| June | 62.0 °F | 84.1 °F | 4.52 in. |
| July | 66.1 °F | 88.1 °F | 3.93 in. |
| August | 63.7 °F | 86.6 °F | 3.39 in. |
| September | 54.3 °F | 79.6 °F | 2.99 in. |
| October | 41.6 °F | 66.9 °F | 2.33 in. |
| November | 28.8 °F | 51.5 °F | 1.36 in. |
| December | 19.2 °F | 39.1 °F | 1.07 in. |
| Annual | 40.9 °F | 63.4 °F | 30.84 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |