Killeen, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.8 °F (low) to 78.5 °F (high). Annual precipitation averages 34 Inches. Killeen is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 36.8 °F | 59.9 °F | 2.22 in. |
| February | 40.5 °F | 63.6 °F | 2.25 in. |
| March | 47.7 °F | 70.5 °F | 3.17 in. |
| April | 55.1 °F | 78.2 °F | 2.57 in. |
| May | 63.8 °F | 84.7 °F | 4.62 in. |
| June | 70.7 °F | 91.8 °F | 3.17 in. |
| July | 73.1 °F | 95.4 °F | 1.82 in. |
| August | 73.0 °F | 96.4 °F | 2.49 in. |
| September | 66.9 °F | 89.9 °F | 3.03 in. |
| October | 56.7 °F | 80.5 °F | 3.62 in. |
| November | 46.4 °F | 69.4 °F | 2.65 in. |
| December | 38.6 °F | 61.2 °F | 2.43 in. |
| Annual | 55.8 °F | 78.5 °F | 34.04 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |