McKinney, Kentucky has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.5 °C (low) to 18.9 °C (high). Annual precipitation averages 1287.8 Millimeters. McKinney is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around Apr. 11 - Apr. 20 through the first frost around Oct. 21 - Oct. 31.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.8 °C | 6.1 °C | 99.31 mm |
| February | -2.1 °C | 8.4 °C | 96.01 mm |
| March | 1.6 °C | 13.6 °C | 123.44 mm |
| April | 6.8 °C | 19.4 °C | 118.36 mm |
| May | 12.4 °C | 23.9 °C | 132.08 mm |
| June | 16.8 °C | 28.2 °C | 134.37 mm |
| July | 18.8 °C | 29.7 °C | 116.59 mm |
| August | 17.7 °C | 29.6 °C | 89.66 mm |
| September | 13.9 °C | 26.5 °C | 99.31 mm |
| October | 7.8 °C | 20.4 °C | 83.31 mm |
| November | 1.7 °C | 13.5 °C | 83.57 mm |
| December | -1.6 °C | 7.9 °C | 111.76 mm |
| Annual | 7.5 °C | 18.9 °C | 1287.77 mm |
| Average First Frost Date | Oct. 21 - Oct. 31 |
| Average Last Frost Date | Apr. 11 - Apr. 20 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |