Logan, Iowa has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 3.8 °C (low) to 15.9 °C (high). Annual precipitation averages 852.9 Millimeters. Logan is located in USDA Plant Hardiness Zone 5b. 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 | -11.2 °C | -0.6 °C | 18.8 mm |
| February | -9.1 °C | 2.2 °C | 24.38 mm |
| March | -2.9 °C | 9.4 °C | 47.24 mm |
| April | 3.2 °C | 16.6 °C | 84.33 mm |
| May | 10.1 °C | 22.5 °C | 125.22 mm |
| June | 16.1 °C | 28 °C | 131.57 mm |
| July | 18.2 °C | 29.8 °C | 98.55 mm |
| August | 16.7 °C | 28.7 °C | 106.68 mm |
| September | 11.4 °C | 25.3 °C | 82.55 mm |
| October | 4.4 °C | 18.1 °C | 64.52 mm |
| November | -2.7 °C | 9.3 °C | 36.07 mm |
| December | -8.4 °C | 1.9 °C | 33.02 mm |
| Annual | 3.8 °C | 15.9 °C | 852.93 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 5b : -26.1°C to -23.3°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 |