Gustine, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.7 °C (low) to 25.3 °C (high). Annual precipitation averages 808.7 Millimeters. Gustine is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.9 °C | 14.7 °C | 44.96 mm |
| February | 2.8 °C | 16.8 °C | 54.86 mm |
| March | 7 °C | 20.8 °C | 69.34 mm |
| April | 11.1 °C | 25.2 °C | 65.02 mm |
| May | 16.3 °C | 28.9 °C | 109.22 mm |
| June | 20.3 °C | 32.9 °C | 98.55 mm |
| July | 21.9 °C | 35.2 °C | 47.5 mm |
| August | 21.8 °C | 35.5 °C | 59.18 mm |
| September | 17.8 °C | 31.5 °C | 73.41 mm |
| October | 11.9 °C | 26.4 °C | 85.6 mm |
| November | 6.3 °C | 19.9 °C | 55.37 mm |
| December | 1.9 °C | 15.4 °C | 45.72 mm |
| Annual | 11.7 °C | 25.3 °C | 808.73 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |