Allenville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 43.4 °F (low) to 63.6 °F (high). Annual precipitation averages 40.9 Inches. Allenville is located in USDA Plant Hardiness Zone 6a. 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 | 19.9 °F | 35.8 °F | 2.43 in. |
| February | 22.6 °F | 40.5 °F | 2.2 in. |
| March | 31.8 °F | 51.7 °F | 2.95 in. |
| April | 42.7 °F | 64.4 °F | 4.55 in. |
| May | 53.9 °F | 74.8 °F | 4.74 in. |
| June | 62.6 °F | 83.4 °F | 4.72 in. |
| July | 65.6 °F | 86.3 °F | 4.08 in. |
| August | 63.6 °F | 85.2 °F | 2.88 in. |
| September | 55.1 °F | 80.1 °F | 3.0 in. |
| October | 43.9 °F | 67.6 °F | 3.39 in. |
| November | 33.4 °F | 52.3 °F | 3.37 in. |
| December | 25.6 °F | 40.6 °F | 2.57 in. |
| Annual | 43.4 °F | 63.6 °F | 40.88 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°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 |