Richwood, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12 °C (low) to 24.7 °C (high). Annual precipitation averages 1446 Millimeters. Richwood 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 | 1.7 °C | 13.4 °C | 138.94 mm |
| February | 3.3 °C | 15.9 °C | 127.51 mm |
| March | 7.3 °C | 20.3 °C | 140.72 mm |
| April | 11.4 °C | 24.8 °C | 152.4 mm |
| May | 16.7 °C | 28.9 °C | 124.46 mm |
| June | 20.8 °C | 32.5 °C | 111.25 mm |
| July | 22.4 °C | 33.9 °C | 105.66 mm |
| August | 21.7 °C | 34.4 °C | 88.65 mm |
| September | 18.1 °C | 31.7 °C | 88.65 mm |
| October | 11.7 °C | 26.2 °C | 109.98 mm |
| November | 6.2 °C | 19.5 °C | 119.13 mm |
| December | 2.8 °C | 14.9 °C | 138.68 mm |
| Annual | 12 °C | 24.7 °C | 1446.03 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |