De Leon, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.5 °C (low) to 24.9 °C (high). Annual precipitation averages 815.9 Millimeters. De Leon 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 | 0.6 °C | 14.3 °C | 42.42 mm |
| February | 2.6 °C | 16.4 °C | 53.59 mm |
| March | 6.7 °C | 20.4 °C | 69.6 mm |
| April | 10.7 °C | 24.8 °C | 63.25 mm |
| May | 16.1 °C | 28.7 °C | 110.74 mm |
| June | 20.1 °C | 32.6 °C | 103.63 mm |
| July | 21.8 °C | 34.9 °C | 49.02 mm |
| August | 21.6 °C | 35.2 °C | 63.5 mm |
| September | 17.7 °C | 31.2 °C | 77.22 mm |
| October | 11.7 °C | 26 °C | 85.85 mm |
| November | 6.1 °C | 19.5 °C | 50.29 mm |
| December | 1.7 °C | 14.9 °C | 46.74 mm |
| Annual | 11.5 °C | 24.9 °C | 815.85 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 |