De Witt, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.4 °C (low) to 17.7 °C (high). Annual precipitation averages 1040.9 Millimeters. De Witt is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.6 °C | 2.6 °C | 34.04 mm |
| February | -5.4 °C | 5.5 °C | 46.74 mm |
| March | 0.1 °C | 12 °C | 69.09 mm |
| April | 5.9 °C | 18.1 °C | 105.66 mm |
| May | 12.1 °C | 23.4 °C | 141.73 mm |
| June | 17.5 °C | 28.3 °C | 137.67 mm |
| July | 19.7 °C | 30.5 °C | 113.28 mm |
| August | 18.3 °C | 29.8 °C | 102.36 mm |
| September | 13.3 °C | 25.9 °C | 99.06 mm |
| October | 6.8 °C | 19.4 °C | 82.55 mm |
| November | 0.5 °C | 11.7 °C | 62.48 mm |
| December | -4.8 °C | 4.9 °C | 46.23 mm |
| Annual | 6.4 °C | 17.7 °C | 1040.89 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |