Winona, Missouri has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.7 °C (low) to 20 °C (high). Annual precipitation averages 1254.8 Millimeters. Winona 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5.3 °C | 6.8 °C | 73.15 mm |
| February | -3.6 °C | 9.5 °C | 79.5 mm |
| March | 0.8 °C | 14.9 °C | 117.86 mm |
| April | 6.3 °C | 20.8 °C | 144.02 mm |
| May | 11.8 °C | 24.9 °C | 144.27 mm |
| June | 16.5 °C | 29.1 °C | 101.35 mm |
| July | 18.8 °C | 31.5 °C | 106.68 mm |
| August | 17.8 °C | 31.1 °C | 92.71 mm |
| September | 13.1 °C | 27.2 °C | 94.49 mm |
| October | 6.3 °C | 21.3 °C | 95 mm |
| November | 1.1 °C | 14.3 °C | 122.17 mm |
| December | -3.4 °C | 8.3 °C | 83.57 mm |
| Annual | 6.7 °C | 20 °C | 1254.77 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 6b : -20.6°C to -17.8°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |