Rossmoyne, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.2 °C (low) to 18.1 °C (high). Annual precipitation averages 1128 Millimeters. Rossmoyne is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.8 °C | 4 °C | 84.07 mm |
| February | -3.8 °C | 6.3 °C | 72.39 mm |
| March | 0.8 °C | 11.8 °C | 99.57 mm |
| April | 6.6 °C | 18.8 °C | 116.08 mm |
| May | 12.2 °C | 23.7 °C | 124.46 mm |
| June | 17.1 °C | 28.4 °C | 114.3 mm |
| July | 18.8 °C | 30 °C | 100.84 mm |
| August | 17.9 °C | 29.8 °C | 88.9 mm |
| September | 13.9 °C | 26.3 °C | 74.68 mm |
| October | 7.6 °C | 19.8 °C | 80.52 mm |
| November | 1.8 °C | 12.1 °C | 83.82 mm |
| December | -2.2 °C | 6.2 °C | 88.39 mm |
| Annual | 7.2 °C | 18.1 °C | 1128.02 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 |