Hills, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.7 °C (low) to 15.8 °C (high). Annual precipitation averages 946.7 Millimeters. Hills is located in USDA Plant Hardiness Zone 5b. 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 | -10 °C | -0.8 °C | 30.99 mm |
| February | -8.1 °C | 1.7 °C | 37.34 mm |
| March | -1.9 °C | 8.9 °C | 58.93 mm |
| April | 4.2 °C | 16.7 °C | 95.5 mm |
| May | 10.9 °C | 22.7 °C | 119.89 mm |
| June | 16.5 °C | 27.8 °C | 130.81 mm |
| July | 18.4 °C | 29.7 °C | 107.7 mm |
| August | 17 °C | 28.6 °C | 105.41 mm |
| September | 12.2 °C | 25.3 °C | 86.61 mm |
| October | 5.5 °C | 17.9 °C | 74.93 mm |
| November | -1.1 °C | 9.4 °C | 56.13 mm |
| December | -6.9 °C | 2 °C | 42.42 mm |
| Annual | 4.7 °C | 15.8 °C | 946.66 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°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 |