Winfield, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.3 °C (low) to 18.7 °C (high). Annual precipitation averages 1037.9 Millimeters. Winfield is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.8 °C | 3.8 °C | 55.12 mm |
| February | -4.1 °C | 6.9 °C | 52.83 mm |
| March | 0.8 °C | 12.7 °C | 77.22 mm |
| April | 6.8 °C | 19.4 °C | 107.19 mm |
| May | 12.9 °C | 24.4 °C | 122.43 mm |
| June | 17.9 °C | 29.2 °C | 122.17 mm |
| July | 19.9 °C | 31.1 °C | 97.03 mm |
| August | 18.8 °C | 30.5 °C | 88.39 mm |
| September | 14 °C | 26.8 °C | 86.87 mm |
| October | 7.6 °C | 20.3 °C | 83.06 mm |
| November | 1.6 °C | 12.7 °C | 81.79 mm |
| December | -3.3 °C | 6.3 °C | 63.75 mm |
| Annual | 7.3 °C | 18.7 °C | 1037.85 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |