Athens, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.6 °F (low) to 62.8 °F (high). Annual precipitation averages 38.8 Inches. Athens 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.2 °F | 34.9 °F | 2.13 in. |
| February | 21.6 °F | 39.7 °F | 1.92 in. |
| March | 30.8 °F | 51.4 °F | 2.65 in. |
| April | 41.5 °F | 64.3 °F | 3.99 in. |
| May | 53.1 °F | 74.1 °F | 4.55 in. |
| June | 62.4 °F | 82.4 °F | 4.57 in. |
| July | 65.4 °F | 85.5 °F | 3.79 in. |
| August | 63.2 °F | 84.1 °F | 3.5 in. |
| September | 54.9 °F | 78.9 °F | 3.22 in. |
| October | 43.3 °F | 66.5 °F | 3.24 in. |
| November | 32.6 °F | 52.0 °F | 3.02 in. |
| December | 23.7 °F | 40.1 °F | 2.21 in. |
| Annual | 42.6 °F | 62.8 °F | 38.79 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |