Simmesport, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 56.6 °F (low) to 77.5 °F (high). Annual precipitation averages 60.6 Inches. Simmesport is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 39.3 °F | 60.1 °F | 6.52 in. |
| February | 43.0 °F | 64.3 °F | 5.06 in. |
| March | 49.2 °F | 71.5 °F | 4.74 in. |
| April | 56.0 °F | 77.5 °F | 5.18 in. |
| May | 64.4 °F | 84.1 °F | 5.01 in. |
| June | 70.8 °F | 89.6 °F | 5.46 in. |
| July | 72.8 °F | 91.5 °F | 4.73 in. |
| August | 72.1 °F | 91.9 °F | 4.67 in. |
| September | 67.5 °F | 87.8 °F | 4.37 in. |
| October | 56.7 °F | 79.8 °F | 4.17 in. |
| November | 46.3 °F | 69.7 °F | 5.16 in. |
| December | 41.3 °F | 62.4 °F | 5.5 in. |
| Annual | 56.6 °F | 77.5 °F | 60.57 in. |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |