Mitchell, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 8.3 °C (low) to 18.8 °C (high). Annual precipitation averages 1124.5 Millimeters. Mitchell is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -5 °C | 4.1 °C | 66.8 mm |
| February | -2.9 °C | 7.1 °C | 61.47 mm |
| March | 1.8 °C | 12.6 °C | 87.12 mm |
| April | 7.9 °C | 19.4 °C | 122.94 mm |
| May | 13.8 °C | 24.4 °C | 135.64 mm |
| June | 18.8 °C | 29.3 °C | 115.82 mm |
| July | 20.9 °C | 31.2 °C | 107.19 mm |
| August | 19.9 °C | 30.5 °C | 100.33 mm |
| September | 15.2 °C | 26.9 °C | 82.8 mm |
| October | 8.6 °C | 20.6 °C | 83.31 mm |
| November | 2.6 °C | 12.9 °C | 92.2 mm |
| December | -2.4 °C | 6.7 °C | 68.83 mm |
| Annual | 8.3 °C | 18.8 °C | 1124.45 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |