Seguin, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 14.3 °C (low) to 27.1 °C (high). Annual precipitation averages 854.2 Millimeters. Seguin is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.6 °C | 17.3 °C | 52.07 mm |
| February | 6.4 °C | 19.7 °C | 48.51 mm |
| March | 10.4 °C | 23.2 °C | 66.04 mm |
| April | 13.9 °C | 27.1 °C | 67.31 mm |
| May | 18.6 °C | 30.7 °C | 101.35 mm |
| June | 21.9 °C | 33.8 °C | 84.33 mm |
| July | 23 °C | 35.4 °C | 55.12 mm |
| August | 22.9 °C | 36 °C | 64.26 mm |
| September | 20.1 °C | 32.6 °C | 86.11 mm |
| October | 15 °C | 28.4 °C | 103.38 mm |
| November | 9.4 °C | 22.4 °C | 67.31 mm |
| December | 5.4 °C | 18.1 °C | 58.42 mm |
| Annual | 14.3 °C | 27.1 °C | 854.21 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| Average Days With Frost | 10-20 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 | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |