Grey Forest, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 55.9 °F (low) to 78.7 °F (high). Annual precipitation averages 37.7 Inches. Grey Forest 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 | 38.2 °F | 61.7 °F | 2.12 in. |
| February | 42.0 °F | 66.1 °F | 2.03 in. |
| March | 48.6 °F | 72.2 °F | 2.75 in. |
| April | 55.1 °F | 78.7 °F | 2.56 in. |
| May | 63.7 °F | 84.7 °F | 4.66 in. |
| June | 69.9 °F | 90.7 °F | 3.97 in. |
| July | 71.6 °F | 93.3 °F | 2.82 in. |
| August | 71.5 °F | 94.5 °F | 3.01 in. |
| September | 66.5 °F | 88.7 °F | 4.22 in. |
| October | 57.2 °F | 80.6 °F | 4.25 in. |
| November | 47.1 °F | 70.4 °F | 2.97 in. |
| December | 39.8 °F | 63.0 °F | 2.29 in. |
| Annual | 55.9 °F | 78.7 °F | 37.65 in. |
| 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 : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |