Fort Jesup, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.9 °C (low) to 25.1 °C (high). Annual precipitation averages 1414.3 Millimeters. Fort Jesup is located in USDA Plant Hardiness Zone 9a. 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 | 3.1 °C | 14.9 °C | 142.49 mm |
| February | 4.9 °C | 17.3 °C | 118.11 mm |
| March | 8.6 °C | 21.4 °C | 131.32 mm |
| April | 12.6 °C | 25.1 °C | 125.48 mm |
| May | 17.2 °C | 29 °C | 114.3 mm |
| June | 21.1 °C | 32.3 °C | 117.09 mm |
| July | 22.4 °C | 33.7 °C | 98.3 mm |
| August | 21.9 °C | 34.1 °C | 99.57 mm |
| September | 18.8 °C | 31.3 °C | 89.15 mm |
| October | 12.7 °C | 26.3 °C | 113.28 mm |
| November | 7.3 °C | 20.4 °C | 122.17 mm |
| December | 4.1 °C | 15.9 °C | 143 mm |
| Annual | 12.9 °C | 25.1 °C | 1414.26 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 20-30 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°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 |