Percival, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.5 °C (low) to 17.1 °C (high). Annual precipitation averages 851.2 Millimeters. Percival 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. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.4 °C | 1 °C | 20.32 mm |
| February | -7.9 °C | 3.9 °C | 26.42 mm |
| March | -1.9 °C | 11.1 °C | 46.23 mm |
| April | 4 °C | 17.8 °C | 84.07 mm |
| May | 10.9 °C | 23.3 °C | 136.65 mm |
| June | 16.7 °C | 28.5 °C | 125.73 mm |
| July | 18.8 °C | 30.5 °C | 107.19 mm |
| August | 17.2 °C | 29.6 °C | 85.6 mm |
| September | 11.9 °C | 26.1 °C | 79.5 mm |
| October | 4.9 °C | 19.6 °C | 68.83 mm |
| November | -2.1 °C | 10.5 °C | 39.12 mm |
| December | -7.6 °C | 3.5 °C | 31.5 mm |
| Annual | 4.5 °C | 17.1 °C | 851.16 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5b : -26.1°C to -23.3°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |