Montegut, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 15.7 °C (low) to 25.6 °C (high). Annual precipitation averages 1662.2 Millimeters. Montegut is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 6.6 °C | 17.2 °C | 136.4 mm |
| February | 8.6 °C | 19.2 °C | 104.39 mm |
| March | 11.9 °C | 22.2 °C | 108.97 mm |
| April | 15.6 °C | 25.2 °C | 124.71 mm |
| May | 19.7 °C | 28.9 °C | 137.67 mm |
| June | 22.8 °C | 31.4 °C | 191.52 mm |
| July | 23.7 °C | 32.3 °C | 204.22 mm |
| August | 23.4 °C | 32.6 °C | 193.8 mm |
| September | 21.7 °C | 30.8 °C | 148.59 mm |
| October | 16.5 °C | 27.1 °C | 105.66 mm |
| November | 10.7 °C | 21.9 °C | 95.76 mm |
| December | 7.7 °C | 18.4 °C | 110.49 mm |
| Annual | 15.7 °C | 25.6 °C | 1662.18 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |