Sour Lake, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 14.7 °C (low) to 25.8 °C (high). Annual precipitation averages 1560.1 Millimeters. 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 | 5.3 °C | 16.6 °C | 126.49 mm |
| February | 7.3 °C | 18.7 °C | 97.03 mm |
| March | 10.7 °C | 22.3 °C | 100.08 mm |
| April | 14.4 °C | 25.6 °C | 102.62 mm |
| May | 18.9 °C | 29.2 °C | 128.52 mm |
| June | 22.2 °C | 32.3 °C | 166.88 mm |
| July | 23.2 °C | 33.3 °C | 133.1 mm |
| August | 22.9 °C | 33.6 °C | 152.65 mm |
| September | 20.3 °C | 31.3 °C | 152.91 mm |
| October | 14.7 °C | 27.2 °C | 145.03 mm |
| November | 9.6 °C | 21.7 °C | 123.44 mm |
| December | 6.3 °C | 17.6 °C | 131.32 mm |
| Annual | 14.7 °C | 25.8 °C | 1560.07 mm |
| 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 : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |