Spring Branch, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.3 °C (low) to 26.1 °C (high). Annual precipitation averages 894.3 Millimeters. Spring Branch 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. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.3 °C | 16.3 °C | 57.91 mm |
| February | 5.4 °C | 18.5 °C | 49.53 mm |
| March | 9.1 °C | 22.2 °C | 69.34 mm |
| April | 12.8 °C | 26.2 °C | 63.25 mm |
| May | 17.7 °C | 29.6 °C | 114.3 mm |
| June | 21.2 °C | 33 °C | 87.38 mm |
| July | 22.2 °C | 34.6 °C | 54.61 mm |
| August | 22.1 °C | 35.4 °C | 61.21 mm |
| September | 19.2 °C | 32.1 °C | 97.54 mm |
| October | 13.8 °C | 27.4 °C | 109.98 mm |
| November | 8.3 °C | 21.2 °C | 72.14 mm |
| December | 4.2 °C | 17.1 °C | 57.15 mm |
| Annual | 13.3 °C | 26.1 °C | 894.34 mm |
| 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 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 |