Smithville, Mississippi has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 51.1 °F (low) to 74.1 °F (high). Annual precipitation averages 57.4 Inches. Smithville is located in USDA Plant Hardiness Zone 8a. The growing season typically runs from the last frost around Mar. 21 - Mar. 31 through the first frost around Nov. 1 - Nov. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 31.8 °F | 52.7 °F | 5.24 in. |
| February | 35.0 °F | 57.5 °F | 5.34 in. |
| March | 42.0 °F | 66.4 °F | 5.15 in. |
| April | 50.1 °F | 74.6 °F | 5.52 in. |
| May | 59.2 °F | 82.4 °F | 5.22 in. |
| June | 67.3 °F | 89.2 °F | 4.64 in. |
| July | 70.7 °F | 91.8 °F | 4.49 in. |
| August | 69.5 °F | 92.0 °F | 3.95 in. |
| September | 62.6 °F | 86.5 °F | 3.85 in. |
| October | 50.4 °F | 76.4 °F | 3.69 in. |
| November | 39.7 °F | 64.3 °F | 4.42 in. |
| December | 34.7 °F | 55.4 °F | 5.93 in. |
| Annual | 51.1 °F | 74.1 °F | 57.44 in. |
| Average First Frost Date | Nov. 1 - Nov. 10 |
| Average Last Frost Date | Mar. 21 - Mar. 31 |
| Average Days With Frost | 50-75 Days |
| Plant Hardiness Zone | Zone 8a : 10°F to 15°F |
| Plant Hardiness Zone - 2012 | Zone 7b : 5°F to 10°F |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |