Salem, Ohio has a Humid Continental Mild Summer, Wet All Year climate (Köppen classification: Dfb). Average annual temperatures range from 39.2 °F (low) to 59.9 °F (high). Annual precipitation averages 40.6 Inches. Salem is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 17.9 °F | 34.0 °F | 2.91 in. |
| February | 18.8 °F | 37.0 °F | 2.29 in. |
| March | 26.8 °F | 46.5 °F | 3.13 in. |
| April | 37.5 °F | 60.1 °F | 4.09 in. |
| May | 47.2 °F | 70.6 °F | 3.66 in. |
| June | 56.5 °F | 79.0 °F | 4.26 in. |
| July | 60.2 °F | 82.6 °F | 4.36 in. |
| August | 58.1 °F | 81.3 °F | 3.07 in. |
| September | 51.4 °F | 75.3 °F | 3.84 in. |
| October | 40.5 °F | 63.2 °F | 3.2 in. |
| November | 31.8 °F | 49.8 °F | 2.91 in. |
| December | 23.9 °F | 39.0 °F | 2.9 in. |
| Annual | 39.2 °F | 59.9 °F | 40.62 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 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 | Dfb - Humid Continental Mild Summer, Wet All Year |