Mackey, Indiana has a Humid Continental Hot Summers With Year Around Precipitation climate (Köppen classification: Dfa). Average annual temperatures range from 7.8 °C (low) to 19.3 °C (high). Annual precipitation averages 1254 Millimeters. Mackey is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -4.4 °C | 4.9 °C | 90.68 mm |
| February | -3 °C | 7.6 °C | 78.49 mm |
| March | 1.7 °C | 13.1 °C | 111 mm |
| April | 7.4 °C | 19.9 °C | 135.13 mm |
| May | 13.2 °C | 25.1 °C | 138.43 mm |
| June | 18.1 °C | 29.6 °C | 121.41 mm |
| July | 19.8 °C | 31.2 °C | 111 mm |
| August | 18.7 °C | 30.8 °C | 78.74 mm |
| September | 14.4 °C | 27.6 °C | 95 mm |
| October | 8 °C | 21.2 °C | 90.17 mm |
| November | 2.2 °C | 13.3 °C | 104.65 mm |
| December | -2.2 °C | 7.2 °C | 99.31 mm |
| Annual | 7.8 °C | 19.3 °C | 1254.01 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7a : -17.8°C to -15°C |
| Plant Hardiness Zone - 2012 | Zone 6b : -20.6°C to -17.8°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Dfa - Humid Continental Hot Summers With Year Around Precipitation |