Mason, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 44.3 °F (low) to 64.1 °F (high). Annual precipitation averages 43.9 Inches. Mason is located in USDA Plant Hardiness Zone 6b. 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 | 22.7 °F | 38.8 °F | 3.25 in. |
| February | 24.5 °F | 42.9 °F | 2.73 in. |
| March | 32.7 °F | 52.7 °F | 3.86 in. |
| April | 42.9 °F | 64.8 °F | 4.6 in. |
| May | 53.4 °F | 74.2 °F | 4.91 in. |
| June | 62.3 °F | 82.1 °F | 4.46 in. |
| July | 65.8 °F | 85.6 °F | 4.09 in. |
| August | 63.8 °F | 84.9 °F | 3.54 in. |
| September | 56.6 °F | 79.0 °F | 2.84 in. |
| October | 44.7 °F | 67.0 °F | 3.1 in. |
| November | 34.4 °F | 53.6 °F | 3.12 in. |
| December | 27.7 °F | 43.0 °F | 3.42 in. |
| Annual | 44.3 °F | 64.1 °F | 43.92 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6b : -5°F to 0°F |
| Plant Hardiness Zone - 2012 | Zone 6a : -10°F to -5°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |