McKinney, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 54.8 °F (low) to 76 °F (high). Annual precipitation averages 41.5 Inches. McKinney is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 34.3 °F | 55.5 °F | 2.72 in. |
| February | 37.9 °F | 59.8 °F | 2.99 in. |
| March | 45.8 °F | 67.4 °F | 3.89 in. |
| April | 53.4 °F | 75.1 °F | 3.82 in. |
| May | 63.0 °F | 82.6 °F | 5.05 in. |
| June | 71.2 °F | 90.5 °F | 3.81 in. |
| July | 74.6 °F | 94.9 °F | 2.15 in. |
| August | 74.0 °F | 95.6 °F | 2.2 in. |
| September | 66.8 °F | 88.5 °F | 3.12 in. |
| October | 55.5 °F | 78.4 °F | 4.65 in. |
| November | 44.7 °F | 66.2 °F | 3.53 in. |
| December | 36.5 °F | 57.4 °F | 3.53 in. |
| Annual | 54.8 °F | 76 °F | 41.46 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |