McClelland, 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 16 °C (high). Annual precipitation averages 857.8 Millimeters. McClelland is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around Apr. 21 - Apr. 30 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -10.3 °C | -0.2 °C | 18.54 mm |
| February | -8.2 °C | 2.4 °C | 24.89 mm |
| March | -2.3 °C | 9.6 °C | 45.72 mm |
| April | 3.8 °C | 16.7 °C | 85.85 mm |
| May | 10.6 °C | 22.5 °C | 134.11 mm |
| June | 16.5 °C | 27.9 °C | 129.29 mm |
| July | 18.7 °C | 29.9 °C | 94.74 mm |
| August | 17.2 °C | 28.8 °C | 103.89 mm |
| September | 12.1 °C | 25.4 °C | 79.5 mm |
| October | 5.2 °C | 18.1 °C | 67.82 mm |
| November | -1.8 °C | 9.2 °C | 39.12 mm |
| December | -7.3 °C | 2.2 °C | 34.29 mm |
| Annual | 4.5 °C | 16 °C | 857.76 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |