Earlville, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.1 °C (low) to 15.2 °C (high). Annual precipitation averages 969 Millimeters. 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 | -10.1 °C | -1.2 °C | 44.96 mm |
| February | -8 °C | 1.3 °C | 44.7 mm |
| March | -2.6 °C | 8.2 °C | 59.18 mm |
| April | 3.2 °C | 15.7 °C | 92.2 mm |
| May | 9.8 °C | 22.1 °C | 118.87 mm |
| June | 15.2 °C | 27.1 °C | 117.35 mm |
| July | 17.2 °C | 28.7 °C | 106.43 mm |
| August | 16 °C | 27.7 °C | 99.31 mm |
| September | 11.4 °C | 24.6 °C | 89.15 mm |
| October | 4.9 °C | 17.5 °C | 81.28 mm |
| November | -1 °C | 9.1 °C | 64.77 mm |
| December | -6.7 °C | 1.8 °C | 50.8 mm |
| Annual | 4.1 °C | 15.2 °C | 969 mm |
| 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 : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |