McArthur, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 42.6 °F (low) to 64.7 °F (high). Annual precipitation averages 45.1 Inches. McArthur 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 | 21.8 °F | 39.4 °F | 3.51 in. |
| February | 23.7 °F | 43.3 °F | 3.15 in. |
| March | 30.9 °F | 53.2 °F | 4.2 in. |
| April | 41.2 °F | 66.4 °F | 4.28 in. |
| May | 51.4 °F | 75.0 °F | 4.64 in. |
| June | 60.0 °F | 82.7 °F | 4.33 in. |
| July | 63.8 °F | 86.0 °F | 4.47 in. |
| August | 61.9 °F | 85.0 °F | 3.4 in. |
| September | 54.4 °F | 79.3 °F | 3.44 in. |
| October | 42.4 °F | 67.3 °F | 3.18 in. |
| November | 32.9 °F | 54.5 °F | 3.15 in. |
| December | 26.8 °F | 43.7 °F | 3.36 in. |
| Annual | 42.6 °F | 64.7 °F | 45.11 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 |