Sherman, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.6 °C (low) to 23.4 °C (high). Annual precipitation averages 1087.9 Millimeters. Sherman is located in USDA Plant Hardiness Zone 8a. 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 | 0.2 °C | 11.7 °C | 60.2 mm |
| February | 2.1 °C | 14.1 °C | 68.07 mm |
| March | 6.3 °C | 18.5 °C | 100.58 mm |
| April | 10.6 °C | 22.8 °C | 90.93 mm |
| May | 16 °C | 26.9 °C | 136.65 mm |
| June | 20.7 °C | 31.6 °C | 108.97 mm |
| July | 22.9 °C | 34.3 °C | 71.63 mm |
| August | 22.6 °C | 34.5 °C | 71.12 mm |
| September | 18.4 °C | 30.4 °C | 91.69 mm |
| October | 12.1 °C | 24.6 °C | 115.06 mm |
| November | 6.2 °C | 18.1 °C | 86.11 mm |
| December | 1.5 °C | 12.8 °C | 86.87 mm |
| Annual | 11.6 °C | 23.4 °C | 1087.88 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 8a : -12.2°C to -9.4°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 |