Sundown, Texas has a Cold Semi-Arid Climate climate (Köppen classification: BSk). Average annual temperatures range from 44.8 °F (low) to 74.4 °F (high). Annual precipitation averages 17.7 Inches. Sundown is located in USDA Plant Hardiness Zone 7b. 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 | 24.9 °F | 54.6 °F | 0.62 in. |
| February | 27.9 °F | 59.3 °F | 0.57 in. |
| March | 35.0 °F | 67.3 °F | 1.08 in. |
| April | 42.5 °F | 75.2 °F | 0.99 in. |
| May | 53.0 °F | 83.5 °F | 2.18 in. |
| June | 62.5 °F | 91.2 °F | 2.46 in. |
| July | 65.6 °F | 92.4 °F | 2.14 in. |
| August | 64.1 °F | 91.0 °F | 2.17 in. |
| September | 57.0 °F | 84.0 °F | 2.46 in. |
| October | 45.4 °F | 75.3 °F | 1.51 in. |
| November | 33.4 °F | 63.6 °F | 0.84 in. |
| December | 26.3 °F | 55.5 °F | 0.72 in. |
| Annual | 44.8 °F | 74.4 °F | 17.74 in. |
| 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 7b : 5°F to 10°F |
| Plant Hardiness Zone - 2012 | Zone 7a : 0°F to 5°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | BSk - Cold Semi-Arid Climate |