Stanwood, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.3 °C (low) to 14.6 °C (high). Annual precipitation averages 971.8 Millimeters. Stanwood 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 | -11.6 °C | -2.2 °C | 34.8 mm |
| February | -9.5 °C | 0.4 °C | 40.13 mm |
| March | -3.3 °C | 7.7 °C | 59.18 mm |
| April | 2.8 °C | 15.4 °C | 94.23 mm |
| May | 9.4 °C | 21.6 °C | 115.57 mm |
| June | 15.1 °C | 26.7 °C | 132.84 mm |
| July | 16.9 °C | 28.3 °C | 110.24 mm |
| August | 15.6 °C | 27.4 °C | 111.51 mm |
| September | 10.8 °C | 24.2 °C | 93.98 mm |
| October | 4.2 °C | 16.9 °C | 77.72 mm |
| November | -2.3 °C | 8.3 °C | 57.15 mm |
| December | -8.1 °C | 0.9 °C | 44.45 mm |
| Annual | 3.3 °C | 14.6 °C | 971.8 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 |