Tornillo, Texas has a Cold Desert Climate climate (Köppen classification: BWk). Average annual temperatures range from 48.6 °F (low) to 79.7 °F (high). Annual precipitation averages 7.8 Inches. Tornillo is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 29.2 °F | 60.3 °F | 0.39 in. |
| February | 33.5 °F | 65.9 °F | 0.37 in. |
| March | 40.3 °F | 73.6 °F | 0.22 in. |
| April | 47.3 °F | 81.4 °F | 0.19 in. |
| May | 55.7 °F | 89.3 °F | 0.49 in. |
| June | 65.1 °F | 96.9 °F | 0.69 in. |
| July | 68.9 °F | 95.8 °F | 1.38 in. |
| August | 67.4 °F | 94.1 °F | 1.28 in. |
| September | 61.3 °F | 88.9 °F | 1.04 in. |
| October | 49.0 °F | 81.0 °F | 0.8 in. |
| November | 36.5 °F | 69.3 °F | 0.37 in. |
| December | 29.3 °F | 59.8 °F | 0.61 in. |
| Annual | 48.6 °F | 79.7 °F | 7.83 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | BWk - Cold Desert Climate |