Findlay, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.4 °C (low) to 17.4 °C (high). Annual precipitation averages 1036.1 Millimeters. Findlay 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 | -6.8 °C | 1.9 °C | 61.98 mm |
| February | -5.2 °C | 4.7 °C | 53.85 mm |
| March | -0.1 °C | 10.8 °C | 73.66 mm |
| April | 5.9 °C | 17.9 °C | 114.3 mm |
| May | 12.2 °C | 23.6 °C | 119.89 mm |
| June | 17.1 °C | 28.4 °C | 120.4 mm |
| July | 18.7 °C | 30.1 °C | 100.33 mm |
| August | 17.6 °C | 29.4 °C | 76.71 mm |
| September | 13.2 °C | 26.7 °C | 77.47 mm |
| October | 6.8 °C | 19.7 °C | 86.11 mm |
| November | 0.8 °C | 11.2 °C | 86.61 mm |
| December | -3.7 °C | 4.7 °C | 64.77 mm |
| Annual | 6.4 °C | 17.4 °C | 1036.08 mm |
| 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 : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |