Richwood, Texas has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 61.2 °F (low) to 79.2 °F (high). Annual precipitation averages 48.3 Inches. Richwood is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 44.3 °F | 63.8 °F | 4.05 in. |
| February | 48.2 °F | 66.8 °F | 2.66 in. |
| March | 54.0 °F | 72.4 °F | 3.04 in. |
| April | 60.5 °F | 78.3 °F | 3.2 in. |
| May | 68.1 °F | 84.5 °F | 3.89 in. |
| June | 73.7 °F | 89.8 °F | 4.45 in. |
| July | 75.3 °F | 91.6 °F | 4.01 in. |
| August | 75.0 °F | 92.5 °F | 4.76 in. |
| September | 71.3 °F | 88.9 °F | 6.1 in. |
| October | 63.6 °F | 82.4 °F | 4.28 in. |
| November | 53.9 °F | 73.3 °F | 4.05 in. |
| December | 46.2 °F | 66.0 °F | 3.85 in. |
| Annual | 61.2 °F | 79.2 °F | 48.34 in. |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : 25°F to 20°F |
| Plant Hardiness Zone - 2012 | Zone 9a : 20°F to 25°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |