Toulon, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.5 °C (low) to 15.6 °C (high). Annual precipitation averages 954.8 Millimeters. Toulon is located in USDA Plant Hardiness Zone 5b. 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 | -9.8 °C | -0.7 °C | 46.99 mm |
| February | -7.9 °C | 1.8 °C | 49.28 mm |
| March | -2.2 °C | 8.9 °C | 60.2 mm |
| April | 3.7 °C | 16.3 °C | 92.46 mm |
| May | 10.3 °C | 22.4 °C | 128.52 mm |
| June | 15.8 °C | 27.3 °C | 110.74 mm |
| July | 17.6 °C | 28.9 °C | 92.96 mm |
| August | 16.4 °C | 28.1 °C | 95.25 mm |
| September | 11.7 °C | 24.8 °C | 90.68 mm |
| October | 5.3 °C | 17.8 °C | 73.91 mm |
| November | -1 °C | 9.4 °C | 64.26 mm |
| December | -6.5 °C | 2.3 °C | 49.53 mm |
| Annual | 4.5 °C | 15.6 °C | 954.78 mm |
| 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 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |