Houston, Delaware has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 7.8 °C (low) to 18.9 °C (high). Annual precipitation averages 1196.3 Millimeters. Houston is located in USDA Plant Hardiness Zone 7b. The growing season typically runs from the last frost around Apr. 1 - Apr. 10 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | -3.6 °C | 6.6 °C | 86.87 mm |
| February | -2.9 °C | 7.9 °C | 76.45 mm |
| March | 0.9 °C | 12.2 °C | 108.2 mm |
| April | 6.4 °C | 18.4 °C | 90.68 mm |
| May | 11.8 °C | 23.3 °C | 101.09 mm |
| June | 16.9 °C | 28.2 °C | 103.12 mm |
| July | 19.7 °C | 30.8 °C | 111 mm |
| August | 18.5 °C | 29.6 °C | 119.89 mm |
| September | 15.1 °C | 26.4 °C | 113.03 mm |
| October | 8.9 °C | 20.2 °C | 101.6 mm |
| November | 3.1 °C | 14.4 °C | 82.3 mm |
| December | -1.1 °C | 9.1 °C | 102.11 mm |
| Annual | 7.8 °C | 18.9 °C | 1196.34 mm |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Apr. 1 - Apr. 10 |
| Average Days With Frost | 75-100 Days |
| Plant Hardiness Zone | Zone 7b : -15°C to -12.2°C |
| Plant Hardiness Zone - 2012 | Zone 7a : -17.8°C to -15°C |
| Current Drought Conditions | Extreme Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |