Hawarden, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 2.3 °C (low) to 14.7 °C (high). Annual precipitation averages 743 Millimeters. Hawarden 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 | -13.2 °C | -2.4 °C | 17.53 mm |
| February | -10.8 °C | 0.4 °C | 20.32 mm |
| March | -4.6 °C | 7.4 °C | 42.67 mm |
| April | 1.7 °C | 15.3 °C | 79.5 mm |
| May | 8.6 °C | 21.7 °C | 105.66 mm |
| June | 14.9 °C | 27.3 °C | 114.3 mm |
| July | 17 °C | 29.4 °C | 79.25 mm |
| August | 15.6 °C | 28.3 °C | 81.28 mm |
| September | 10.2 °C | 24.6 °C | 79.25 mm |
| October | 2.9 °C | 16.9 °C | 63.75 mm |
| November | -4.4 °C | 7.8 °C | 34.04 mm |
| December | -10.3 °C | 0 °C | 25.4 mm |
| Annual | 2.3 °C | 14.7 °C | 742.95 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 5a : -28.9°C to -26.1°C |
| Plant Hardiness Zone - 2012 | Zone 5a : -28.9°C to -26.1°C |
| Current Drought Conditions | Abnormally Dry |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |