Liberty, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.1 °C (low) to 16.9 °C (high). Annual precipitation averages 991.9 Millimeters. Liberty is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.7 °C | 1.4 °C | 49.02 mm |
| February | -5.7 °C | 4.2 °C | 51.05 mm |
| March | -0.4 °C | 10.6 °C | 66.04 mm |
| April | 5.7 °C | 17.4 °C | 102.87 mm |
| May | 12 °C | 22.8 °C | 124.46 mm |
| June | 17.2 °C | 27.8 °C | 116.59 mm |
| July | 19.1 °C | 29.9 °C | 100.08 mm |
| August | 17.8 °C | 29.2 °C | 94.23 mm |
| September | 13 °C | 25.7 °C | 86.36 mm |
| October | 6.7 °C | 18.8 °C | 79.5 mm |
| November | 0.7 °C | 10.9 °C | 68.83 mm |
| December | -4.7 °C | 4.1 °C | 52.83 mm |
| Annual | 6.1 °C | 16.9 °C | 991.86 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |