Farley, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.5 °C (low) to 13.3 °C (high). Annual precipitation averages 991.1 Millimeters. Farley is located in USDA Plant Hardiness Zone 5a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 1 - Oct. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -12.8 °C | -3.5 °C | 31.75 mm |
| February | -10.6 °C | -1 °C | 36.58 mm |
| March | -4.2 °C | 6.2 °C | 54.61 mm |
| April | 2 °C | 13.9 °C | 98.3 mm |
| May | 8.6 °C | 20.3 °C | 115.06 mm |
| June | 14.3 °C | 25.6 °C | 149.61 mm |
| July | 16.2 °C | 27.3 °C | 121.67 mm |
| August | 14.9 °C | 26.4 °C | 110.49 mm |
| September | 10 °C | 22.7 °C | 95.5 mm |
| October | 3.4 °C | 15.5 °C | 76.71 mm |
| November | -3.1 °C | 6.8 °C | 57.66 mm |
| December | -8.9 °C | -0.3 °C | 43.18 mm |
| Annual | 2.5 °C | 13.3 °C | 991.12 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| 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 |