Oto, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.8 °C (low) to 15.5 °C (high). Annual precipitation averages 797 Millimeters. Oto 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 | -12.2 °C | -1.5 °C | 17.78 mm |
| February | -9.8 °C | 1.3 °C | 22.35 mm |
| March | -3.8 °C | 8.7 °C | 42.42 mm |
| April | 2.1 °C | 16.3 °C | 84.07 mm |
| May | 9 °C | 22.4 °C | 112.01 mm |
| June | 15.1 °C | 27.9 °C | 121.41 mm |
| July | 17.1 °C | 29.7 °C | 95.25 mm |
| August | 15.6 °C | 28.4 °C | 105.66 mm |
| September | 10.6 °C | 25.1 °C | 76.2 mm |
| October | 3.4 °C | 17.9 °C | 56.9 mm |
| November | -3.8 °C | 8.7 °C | 35.56 mm |
| December | -9.4 °C | 1.2 °C | 27.43 mm |
| Annual | 2.8 °C | 15.5 °C | 797.04 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 150-180 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 | Moderate Drought |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |