Hewitt, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.9 °C (low) to 25.3 °C (high). Annual precipitation averages 951 Millimeters. Hewitt 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 | 2.1 °C | 14.6 °C | 68.33 mm |
| February | 4.1 °C | 16.8 °C | 68.07 mm |
| March | 8.2 °C | 20.6 °C | 88.65 mm |
| April | 12.4 °C | 24.9 °C | 78.23 mm |
| May | 17.4 °C | 29 °C | 111.51 mm |
| June | 21.4 °C | 33 °C | 97.54 mm |
| July | 22.9 °C | 35.2 °C | 41.15 mm |
| August | 22.9 °C | 35.7 °C | 60.2 mm |
| September | 19.3 °C | 32.1 °C | 79.5 mm |
| October | 13.3 °C | 26.6 °C | 100.58 mm |
| November | 7.8 °C | 20.1 °C | 76.45 mm |
| December | 3.2 °C | 15.4 °C | 80.77 mm |
| Annual | 12.9 °C | 25.3 °C | 950.98 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 30-40 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°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 |