Delphos, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 40.2 °F (low) to 61 °F (high). Annual precipitation averages 38 Inches. Delphos is located in USDA Plant Hardiness Zone 5b. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 13.6 °F | 32.2 °F | 0.83 in. |
| February | 17.8 °F | 37.4 °F | 1.29 in. |
| March | 28.4 °F | 50.0 °F | 2.22 in. |
| April | 39.3 °F | 62.0 °F | 3.75 in. |
| May | 51.0 °F | 71.8 °F | 5.53 in. |
| June | 60.9 °F | 81.0 °F | 5.31 in. |
| July | 65.1 °F | 85.4 °F | 4.55 in. |
| August | 62.7 °F | 83.8 °F | 4.32 in. |
| September | 53.7 °F | 76.7 °F | 3.69 in. |
| October | 41.4 °F | 64.5 °F | 3.04 in. |
| November | 29.5 °F | 49.5 °F | 2.07 in. |
| December | 19.1 °F | 37.1 °F | 1.4 in. |
| Annual | 40.2 °F | 61 °F | 38 in. |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -15°F to -10°F |
| Plant Hardiness Zone - 2012 | Zone 5b : -15°F to -10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |