Plymouth, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.3 °F (low) to 59.8 °F (high). Annual precipitation averages 41.2 Inches. Plymouth is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 18.0 °F | 33.3 °F | 3.07 in. |
| February | 19.4 °F | 36.1 °F | 2.03 in. |
| March | 27.6 °F | 46.1 °F | 2.89 in. |
| April | 38.0 °F | 60.1 °F | 4.06 in. |
| May | 49.1 °F | 71.1 °F | 4.21 in. |
| June | 58.6 °F | 79.6 °F | 4.65 in. |
| July | 61.8 °F | 83.0 °F | 4.06 in. |
| August | 60.2 °F | 81.4 °F | 3.78 in. |
| September | 53.0 °F | 75.7 °F | 3.6 in. |
| October | 42.2 °F | 63.2 °F | 3.14 in. |
| November | 32.3 °F | 49.5 °F | 2.92 in. |
| December | 23.9 °F | 38.3 °F | 2.74 in. |
| Annual | 40.3 °F | 59.8 °F | 41.15 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -10°F to -5°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 |