Alliance, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 4.7 °C (low) to 15.3 °C (high). Annual precipitation averages 1033.8 Millimeters. Alliance is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.3 °C | 1 °C | 74.68 mm |
| February | -6.8 °C | 2.6 °C | 57.4 mm |
| March | -2.4 °C | 7.9 °C | 80.01 mm |
| April | 3.6 °C | 15.3 °C | 94.23 mm |
| May | 9.1 °C | 21.1 °C | 100.58 mm |
| June | 14.4 °C | 26.1 °C | 110.49 mm |
| July | 16.5 °C | 28.2 °C | 109.22 mm |
| August | 15.4 °C | 27 °C | 88.9 mm |
| September | 11.7 °C | 23.6 °C | 90.17 mm |
| October | 5.6 °C | 17.2 °C | 80.77 mm |
| November | 0.4 °C | 9.8 °C | 73.66 mm |
| December | -4.2 °C | 3.8 °C | 73.66 mm |
| Annual | 4.7 °C | 15.3 °C | 1033.77 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 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 | Normal |
| Köppen Climate Classification | Dfb - Humid Continental Mild Summer, Wet All Year |