Swisher, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.8 °C (low) to 14.9 °C (high). Annual precipitation averages 954.3 Millimeters. Swisher is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -11.2 °C | -1.9 °C | 28.19 mm |
| February | -9.2 °C | 0.6 °C | 34.04 mm |
| March | -2.9 °C | 7.9 °C | 54.36 mm |
| April | 3.3 °C | 15.8 °C | 96.27 mm |
| May | 9.9 °C | 21.8 °C | 112.52 mm |
| June | 15.7 °C | 26.9 °C | 140.97 mm |
| July | 17.5 °C | 28.7 °C | 116.84 mm |
| August | 16.1 °C | 27.7 °C | 108.71 mm |
| September | 11.3 °C | 24.4 °C | 92.2 mm |
| October | 4.6 °C | 17.1 °C | 73.15 mm |
| November | -2.1 °C | 8.6 °C | 55.12 mm |
| December | -7.8 °C | 1.2 °C | 41.91 mm |
| Annual | 3.8 °C | 14.9 °C | 954.28 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |