Riesel, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.2 °C (low) to 25.2 °C (high). Annual precipitation averages 976.9 Millimeters. Riesel is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 2.7 °C | 14.7 °C | 73.66 mm |
| February | 4.7 °C | 16.9 °C | 70.1 mm |
| March | 8.7 °C | 20.7 °C | 92.46 mm |
| April | 12.6 °C | 24.7 °C | 81.03 mm |
| May | 17.6 °C | 28.6 °C | 115.57 mm |
| June | 21.6 °C | 32.7 °C | 87.63 mm |
| July | 23.1 °C | 34.8 °C | 44.7 mm |
| August | 22.8 °C | 35.2 °C | 61.47 mm |
| September | 19.3 °C | 32.1 °C | 81.28 mm |
| October | 13.6 °C | 26.6 °C | 108.46 mm |
| November | 8.1 °C | 20.3 °C | 77.98 mm |
| December | 3.7 °C | 15.6 °C | 82.55 mm |
| Annual | 13.2 °C | 25.2 °C | 976.89 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| 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 |