Sour Lake, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 58.4 °F (low) to 78.4 °F (high). Annual precipitation averages 61.4 Inches. Sour Lake is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 41.5 °F | 61.8 °F | 4.98 in. |
| February | 45.2 °F | 65.7 °F | 3.82 in. |
| March | 51.3 °F | 72.1 °F | 3.94 in. |
| April | 57.9 °F | 78.0 °F | 4.04 in. |
| May | 66.0 °F | 84.6 °F | 5.06 in. |
| June | 72.0 °F | 90.1 °F | 6.57 in. |
| July | 73.7 °F | 92.0 °F | 5.24 in. |
| August | 73.3 °F | 92.5 °F | 6.01 in. |
| September | 68.6 °F | 88.4 °F | 6.02 in. |
| October | 58.5 °F | 80.9 °F | 5.71 in. |
| November | 49.2 °F | 71.1 °F | 4.86 in. |
| December | 43.4 °F | 63.7 °F | 5.17 in. |
| Annual | 58.4 °F | 78.4 °F | 61.42 in. |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |