Butler, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 44.1 °F (low) to 64.2 °F (high). Annual precipitation averages 41.8 Inches. Butler 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 | 20.4 °F | 36.1 °F | 2.73 in. |
| February | 24.1 °F | 41.4 °F | 2.21 in. |
| March | 33.0 °F | 52.5 °F | 3.05 in. |
| April | 43.3 °F | 65.4 °F | 4.9 in. |
| May | 54.3 °F | 75.3 °F | 5.13 in. |
| June | 63.1 °F | 84.0 °F | 4.37 in. |
| July | 66.3 °F | 87.0 °F | 3.81 in. |
| August | 64.0 °F | 85.9 °F | 3.28 in. |
| September | 55.9 °F | 80.3 °F | 2.99 in. |
| October | 44.4 °F | 68.1 °F | 3.34 in. |
| November | 34.5 °F | 52.9 °F | 3.45 in. |
| December | 25.6 °F | 41.1 °F | 2.54 in. |
| Annual | 44.1 °F | 64.2 °F | 41.8 in. |
| 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 : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |