Riverside, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 56.1 °F (low) to 78.9 °F (high). Annual precipitation averages 48.9 Inches. Riverside is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 38.6 °F | 61.1 °F | 4.18 in. |
| February | 42.2 °F | 65.0 °F | 3.54 in. |
| March | 48.5 °F | 71.9 °F | 4.16 in. |
| April | 55.1 °F | 78.5 °F | 3.81 in. |
| May | 63.9 °F | 85.2 °F | 4.53 in. |
| June | 70.2 °F | 91.2 °F | 4.57 in. |
| July | 72.4 °F | 93.8 °F | 3.33 in. |
| August | 72.0 °F | 95.2 °F | 3.99 in. |
| September | 66.6 °F | 89.8 °F | 3.83 in. |
| October | 56.4 °F | 81.4 °F | 4.11 in. |
| November | 46.6 °F | 70.6 °F | 4.49 in. |
| December | 40.2 °F | 62.6 °F | 4.31 in. |
| Annual | 56.1 °F | 78.9 °F | 48.85 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9a : 20°F to 25°F |
| Plant Hardiness Zone - 2012 | Zone 8b : 15°F to 20°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |