Niles, Illinois has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 6 °C (low) to 14.9 °C (high). Annual precipitation averages 985.3 Millimeters. Niles 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 | -7.7 °C | -0.2 °C | 55.12 mm |
| February | -6.2 °C | 1.9 °C | 53.34 mm |
| March | -1.2 °C | 7.5 °C | 57.66 mm |
| April | 4.4 °C | 14.1 °C | 98.3 mm |
| May | 10.4 °C | 20.4 °C | 118.11 mm |
| June | 16.1 °C | 26.1 °C | 112.01 mm |
| July | 19.3 °C | 28.6 °C | 93.47 mm |
| August | 18.6 °C | 27.5 °C | 102.11 mm |
| September | 14.3 °C | 23.8 °C | 86.11 mm |
| October | 7.5 °C | 16.9 °C | 86.11 mm |
| November | 1.1 °C | 9.1 °C | 65.28 mm |
| December | -4.4 °C | 2.8 °C | 57.66 mm |
| Annual | 6 °C | 14.9 °C | 985.28 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 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |