Corunna, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 4.4 °C (low) to 15.4 °C (high). Annual precipitation averages 994.7 Millimeters. Corunna is located in USDA Plant Hardiness Zone 6a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Oct. 11 - Oct. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -8.3 °C | -0.1 °C | 64.01 mm |
| February | -7.3 °C | 2 °C | 54.1 mm |
| March | -2.7 °C | 8.3 °C | 63.25 mm |
| April | 3.2 °C | 15.9 °C | 93.22 mm |
| May | 9.5 °C | 21.9 °C | 115.32 mm |
| June | 14.9 °C | 27 °C | 103.12 mm |
| July | 16.6 °C | 28.8 °C | 97.79 mm |
| August | 15.5 °C | 27.7 °C | 102.36 mm |
| September | 11.3 °C | 24.4 °C | 82.8 mm |
| October | 5.3 °C | 17.3 °C | 77.72 mm |
| November | -0.2 °C | 9.2 °C | 77.72 mm |
| December | -5 °C | 2.6 °C | 63.25 mm |
| Annual | 4.4 °C | 15.4 °C | 994.66 mm |
| Average First Frost Date | Oct. 11 - Oct. 20 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 125-150 Days |
| Plant Hardiness Zone | Zone 6a : -23.3°C to -20.6°C |
| Plant Hardiness Zone - 2012 | Zone 5b : -26.1°C to -23.3°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |