Earlville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 39.4 °F (low) to 59.4 °F (high). Annual precipitation averages 38.2 Inches. Earlville is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.9 °F | 29.9 °F | 1.77 in. |
| February | 17.6 °F | 34.3 °F | 1.76 in. |
| March | 27.4 °F | 46.7 °F | 2.33 in. |
| April | 37.8 °F | 60.3 °F | 3.63 in. |
| May | 49.6 °F | 71.7 °F | 4.68 in. |
| June | 59.4 °F | 80.7 °F | 4.62 in. |
| July | 63.0 °F | 83.6 °F | 4.19 in. |
| August | 60.8 °F | 81.8 °F | 3.91 in. |
| September | 52.6 °F | 76.3 °F | 3.51 in. |
| October | 40.9 °F | 63.5 °F | 3.2 in. |
| November | 30.2 °F | 48.3 °F | 2.55 in. |
| December | 19.9 °F | 35.3 °F | 2.0 in. |
| Annual | 39.4 °F | 59.4 °F | 38.15 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°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 |