Harcourt, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.1 °C (low) to 14.3 °C (high). Annual precipitation averages 905.3 Millimeters. Harcourt 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 | -12.4 °C | -2.8 °C | 22.86 mm |
| February | -10.3 °C | -0.3 °C | 28.7 mm |
| March | -3.8 °C | 7.2 °C | 51.56 mm |
| April | 2.4 °C | 15.2 °C | 95 mm |
| May | 9.4 °C | 21.3 °C | 127.76 mm |
| June | 15.4 °C | 26.8 °C | 135.38 mm |
| July | 17.4 °C | 28.4 °C | 107.44 mm |
| August | 16 °C | 27.2 °C | 111 mm |
| September | 10.9 °C | 24 °C | 81.28 mm |
| October | 4 °C | 16.8 °C | 66.55 mm |
| November | -3.1 °C | 7.8 °C | 43.43 mm |
| December | -9.1 °C | 0.2 °C | 34.29 mm |
| Annual | 3.1 °C | 14.3 °C | 905.25 mm |
| Average First Frost Date | Oct. 1 - Oct. 10 |
| Average Last Frost Date | Apr. 21 - Apr. 30 |
| 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 | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |