Delta, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.2 °F (low) to 59.6 °F (high). Annual precipitation averages 35.9 Inches. Delta 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 | 17.7 °F | 32.3 °F | 2.33 in. |
| February | 19.1 °F | 35.4 °F | 2.03 in. |
| March | 27.2 °F | 45.7 °F | 2.47 in. |
| April | 37.6 °F | 59.3 °F | 3.37 in. |
| May | 49.3 °F | 70.8 °F | 4.01 in. |
| June | 59.2 °F | 80.4 °F | 3.71 in. |
| July | 62.2 °F | 84.1 °F | 3.5 in. |
| August | 60.2 °F | 82.1 °F | 3.55 in. |
| September | 52.5 °F | 76.2 °F | 3.03 in. |
| October | 41.6 °F | 63.2 °F | 2.76 in. |
| November | 31.8 °F | 48.9 °F | 2.78 in. |
| December | 23.6 °F | 37.3 °F | 2.35 in. |
| Annual | 40.2 °F | 59.6 °F | 35.89 in. |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Dfa - Humid Continental Hot Summers With Year Around Precipitation |