Evanston, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6.9 °C (low) to 14.5 °C (high). Annual precipitation averages 1014.5 Millimeters. Evanston 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. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.8 °C | 0.1 °C | 59.69 mm |
| February | -5.1 °C | 2.3 °C | 57.91 mm |
| March | -0.4 °C | 7.6 °C | 56.13 mm |
| April | 4.9 °C | 13.8 °C | 98.55 mm |
| May | 10.6 °C | 19.4 °C | 115.32 mm |
| June | 16.3 °C | 24.7 °C | 113.03 mm |
| July | 20.1 °C | 27.3 °C | 97.28 mm |
| August | 19.9 °C | 26.4 °C | 106.17 mm |
| September | 15.8 °C | 23 °C | 89.66 mm |
| October | 8.8 °C | 16.7 °C | 90.93 mm |
| November | 2.3 °C | 9.2 °C | 68.33 mm |
| December | -3.5 °C | 3 °C | 61.47 mm |
| Annual | 6.9 °C | 14.5 °C | 1014.47 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| 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 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |