Waltonville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.7 °C (low) to 18.8 °C (high). Annual precipitation averages 1170.2 Millimeters. Waltonville 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 | -4.9 °C | 4.3 °C | 77.47 mm |
| February | -3.1 °C | 7.1 °C | 69.6 mm |
| March | 1.7 °C | 12.7 °C | 100.08 mm |
| April | 7.4 °C | 19.3 °C | 125.73 mm |
| May | 13.3 °C | 24.3 °C | 129.29 mm |
| June | 18.1 °C | 29.3 °C | 123.7 mm |
| July | 19.9 °C | 30.9 °C | 106.43 mm |
| August | 18.7 °C | 30.4 °C | 84.07 mm |
| September | 14.1 °C | 26.9 °C | 82.55 mm |
| October | 7.7 °C | 20.7 °C | 86.11 mm |
| November | 2.1 °C | 12.9 °C | 104.9 mm |
| December | -2.5 °C | 6.6 °C | 80.26 mm |
| Annual | 7.7 °C | 18.8 °C | 1170.19 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| 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 |