Columbiana, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 3.9 °C (low) to 15.7 °C (high). Annual precipitation averages 1035.1 Millimeters. Columbiana is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 11 - May 20 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.8 °C | 1.4 °C | 74.68 mm |
| February | -7.4 °C | 3.1 °C | 57.66 mm |
| March | -3.1 °C | 8.3 °C | 78.74 mm |
| April | 2.8 °C | 15.8 °C | 97.54 mm |
| May | 8.2 °C | 21.7 °C | 96.77 mm |
| June | 13.3 °C | 26.3 °C | 109.73 mm |
| July | 15.4 °C | 28.3 °C | 110.49 mm |
| August | 14.3 °C | 27.6 °C | 85.85 mm |
| September | 10.6 °C | 24.3 °C | 96.01 mm |
| October | 4.6 °C | 17.3 °C | 80.77 mm |
| November | -0.2 °C | 10.1 °C | 72.9 mm |
| December | -4.5 °C | 4.1 °C | 73.91 mm |
| Annual | 3.9 °C | 15.7 °C | 1035.05 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 11 - May 20 |
| 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 |