Spencerville, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 41.5 °F (low) to 60.5 °F (high). Annual precipitation averages 39.5 Inches. Spencerville 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 | 18.6 °F | 33.2 °F | 2.67 in. |
| February | 20.5 °F | 36.6 °F | 2.23 in. |
| March | 28.8 °F | 47.3 °F | 2.79 in. |
| April | 39.2 °F | 60.9 °F | 3.83 in. |
| May | 50.7 °F | 71.8 °F | 4.31 in. |
| June | 60.4 °F | 80.6 °F | 4.39 in. |
| July | 63.4 °F | 83.9 °F | 4.34 in. |
| August | 61.4 °F | 82.2 °F | 3.54 in. |
| September | 54.1 °F | 76.9 °F | 3.06 in. |
| October | 43.3 °F | 64.2 °F | 2.83 in. |
| November | 33.0 °F | 49.9 °F | 2.96 in. |
| December | 24.4 °F | 38.1 °F | 2.57 in. |
| Annual | 41.5 °F | 60.5 °F | 39.52 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 |