Graysville, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.5 °C (low) to 17.1 °C (high). Annual precipitation averages 1142.2 Millimeters. Graysville is located in USDA Plant Hardiness Zone 6b. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -6.1 °C | 3.3 °C | 86.36 mm |
| February | -5 °C | 5.2 °C | 73.91 mm |
| March | -1.2 °C | 10.4 °C | 96.77 mm |
| April | 4.6 °C | 17.8 °C | 99.57 mm |
| May | 10 °C | 22.6 °C | 115.06 mm |
| June | 14.8 °C | 27.1 °C | 120.65 mm |
| July | 17.3 °C | 28.9 °C | 117.09 mm |
| August | 16 °C | 28.4 °C | 96.77 mm |
| September | 12.2 °C | 25.3 °C | 91.44 mm |
| October | 5.8 °C | 18.5 °C | 77.98 mm |
| November | 0.7 °C | 11.7 °C | 80.01 mm |
| December | -3 °C | 5.8 °C | 86.61 mm |
| Annual | 5.5 °C | 17.1 °C | 1142.22 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | May 1 - May 10 |
| 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 |