Melvin, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11 °C (low) to 25.5 °C (high). Annual precipitation averages 667.3 Millimeters. Melvin is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 0.3 °C | 15.3 °C | 34.04 mm |
| February | 2.7 °C | 17.5 °C | 39.88 mm |
| March | 6.8 °C | 21.6 °C | 54.86 mm |
| April | 10.2 °C | 25.8 °C | 44.2 mm |
| May | 15.8 °C | 29.6 °C | 92.96 mm |
| June | 19.7 °C | 32.8 °C | 86.36 mm |
| July | 21.1 °C | 34.6 °C | 51.31 mm |
| August | 20.8 °C | 34.8 °C | 50.55 mm |
| September | 17.1 °C | 31.3 °C | 72.64 mm |
| October | 11.4 °C | 26.3 °C | 63.75 mm |
| November | 5.5 °C | 20.3 °C | 44.2 mm |
| December | 0.9 °C | 16.1 °C | 32.51 mm |
| Annual | 11 °C | 25.5 °C | 667.26 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |