Clay, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.9 °C (low) to 26.6 °C (high). Annual precipitation averages 1109.2 Millimeters. Clay is located in USDA Plant Hardiness Zone 9a. 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 | 4.1 °C | 16.5 °C | 88.65 mm |
| February | 6.3 °C | 18.6 °C | 73.91 mm |
| March | 9.8 °C | 22.3 °C | 86.11 mm |
| April | 13.6 °C | 26.2 °C | 83.31 mm |
| May | 18.2 °C | 30.1 °C | 127.51 mm |
| June | 21.8 °C | 33.6 °C | 104.39 mm |
| July | 22.8 °C | 35.2 °C | 55.63 mm |
| August | 22.7 °C | 35.8 °C | 82.55 mm |
| September | 19.8 °C | 32.9 °C | 92.96 mm |
| October | 14.1 °C | 28.1 °C | 120.14 mm |
| November | 8.9 °C | 21.9 °C | 99.82 mm |
| December | 5.1 °C | 17.6 °C | 94.23 mm |
| Annual | 13.9 °C | 26.6 °C | 1109.21 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |