Star Harbor, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 54.7 °F (low) to 77 °F (high). Annual precipitation averages 43.6 Inches. Star Harbor is located in USDA Plant Hardiness Zone 8b. 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 | 36.7 °F | 58.0 °F | 3.28 in. |
| February | 39.4 °F | 62.0 °F | 3.68 in. |
| March | 46.4 °F | 68.5 °F | 4.02 in. |
| April | 52.9 °F | 76.0 °F | 3.67 in. |
| May | 62.4 °F | 83.0 °F | 4.66 in. |
| June | 70.0 °F | 90.1 °F | 4.08 in. |
| July | 72.6 °F | 94.2 °F | 2.17 in. |
| August | 72.0 °F | 95.2 °F | 2.4 in. |
| September | 66.7 °F | 89.1 °F | 3.25 in. |
| October | 55.0 °F | 79.5 °F | 5.2 in. |
| November | 45.2 °F | 68.2 °F | 3.29 in. |
| December | 37.5 °F | 59.7 °F | 3.92 in. |
| Annual | 54.7 °F | 77 °F | 43.62 in. |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : 15°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 8a : 10°F to 15°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |