Greeley, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 1.8 °C (low) to 13.3 °C (high). Annual precipitation averages 991.1 Millimeters. Greeley is located in USDA Plant Hardiness Zone 4b. 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 | -13.8 °C | -3.9 °C | 30.99 mm |
| February | -11.6 °C | -1.4 °C | 33.02 mm |
| March | -4.9 °C | 5.9 °C | 54.36 mm |
| April | 1.3 °C | 13.9 °C | 100.58 mm |
| May | 8 °C | 20.4 °C | 122.17 mm |
| June | 14.1 °C | 26 °C | 149.35 mm |
| July | 15.7 °C | 27.4 °C | 123.19 mm |
| August | 14.3 °C | 26.3 °C | 105.66 mm |
| September | 9.5 °C | 23.1 °C | 95.5 mm |
| October | 2.7 °C | 15.7 °C | 76.96 mm |
| November | -3.9 °C | 6.8 °C | 57.15 mm |
| December | -9.8 °C | -0.6 °C | 42.16 mm |
| Annual | 1.8 °C | 13.3 °C | 991.09 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 4b : -31.7°C to -28.9°C |
| Plant Hardiness Zone - 2012 | Zone 4b : -31.7°C to -28.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |