Tower Hill, 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 17.8 °C (high). Annual precipitation averages 1055.4 Millimeters. Tower Hill is located in USDA Plant Hardiness Zone 6b. 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 | -6.7 °C | 2.3 °C | 64.01 mm |
| February | -4.9 °C | 5.1 °C | 53.85 mm |
| March | 0.1 °C | 11.2 °C | 74.93 mm |
| April | 5.9 °C | 18.5 °C | 115.06 mm |
| May | 12.1 °C | 24 °C | 120.65 mm |
| June | 17 °C | 28.7 °C | 125.22 mm |
| July | 18.7 °C | 30.5 °C | 99.06 mm |
| August | 17.3 °C | 29.8 °C | 77.22 mm |
| September | 13.1 °C | 27 °C | 82.55 mm |
| October | 6.9 °C | 20.1 °C | 87.88 mm |
| November | 0.9 °C | 11.6 °C | 89.15 mm |
| December | -3.7 °C | 5 °C | 65.79 mm |
| Annual | 6.4 °C | 17.8 °C | 1055.37 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 6b : -20.6°C to -17.8°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 |