Delphos, Ohio has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 5.2 °C (low) to 15.7 °C (high). Annual precipitation averages 987.5 Millimeters. Delphos is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -7.6 °C | 0.4 °C | 65.79 mm |
| February | -6.6 °C | 2.3 °C | 55.63 mm |
| March | -1.9 °C | 8.3 °C | 67.82 mm |
| April | 3.8 °C | 15.9 °C | 95.25 mm |
| May | 10.3 °C | 22.1 °C | 110.74 mm |
| June | 15.8 °C | 27 °C | 109.47 mm |
| July | 17.4 °C | 28.9 °C | 106.68 mm |
| August | 16.3 °C | 27.9 °C | 90.42 mm |
| September | 12.2 °C | 24.9 °C | 77.72 mm |
| October | 6.2 °C | 17.8 °C | 71.37 mm |
| November | 0.4 °C | 9.8 °C | 73.91 mm |
| December | -4.4 °C | 3.2 °C | 62.74 mm |
| Annual | 5.2 °C | 15.7 °C | 987.54 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 100-125 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 6a : -23.3°C to -20.6°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |