Montegut, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 60.3 °F (low) to 78.1 °F (high). Annual precipitation averages 65.4 Inches. Montegut is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 43.8 °F | 62.9 °F | 5.37 in. |
| February | 47.5 °F | 66.5 °F | 4.11 in. |
| March | 53.5 °F | 72.0 °F | 4.29 in. |
| April | 60.0 °F | 77.4 °F | 4.91 in. |
| May | 67.4 °F | 84.1 °F | 5.42 in. |
| June | 73.0 °F | 88.6 °F | 7.54 in. |
| July | 74.6 °F | 90.2 °F | 8.04 in. |
| August | 74.2 °F | 90.6 °F | 7.63 in. |
| September | 71.1 °F | 87.4 °F | 5.85 in. |
| October | 61.7 °F | 80.7 °F | 4.16 in. |
| November | 51.2 °F | 71.5 °F | 3.77 in. |
| December | 45.8 °F | 65.2 °F | 4.35 in. |
| Annual | 60.3 °F | 78.1 °F | 65.44 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 | Abnormally Dry |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |