Barnesville, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.1 °F (low) to 60.4 °F (high). Annual precipitation averages 44.5 Inches. Barnesville 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 19.7 °F | 35.6 °F | 3.46 in. |
| February | 21.5 °F | 38.9 °F | 2.52 in. |
| March | 29.0 °F | 48.5 °F | 3.62 in. |
| April | 39.2 °F | 61.4 °F | 4.02 in. |
| May | 49.2 °F | 70.4 °F | 4.34 in. |
| June | 58.6 °F | 78.4 °F | 5.08 in. |
| July | 62.5 °F | 82.0 °F | 4.29 in. |
| August | 60.0 °F | 80.8 °F | 3.68 in. |
| September | 53.3 °F | 75.1 °F | 3.84 in. |
| October | 42.3 °F | 63.0 °F | 3.1 in. |
| November | 33.0 °F | 51.0 °F | 3.23 in. |
| December | 25.3 °F | 40.2 °F | 3.35 in. |
| Annual | 41.1 °F | 60.4 °F | 44.53 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 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 |