Bourg, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 15.6 °C (low) to 25.6 °C (high). Annual precipitation averages 1667.8 Millimeters. Bourg is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 6.4 °C | 17.2 °C | 134.62 mm |
| February | 8.6 °C | 19.2 °C | 107.44 mm |
| March | 11.8 °C | 22.3 °C | 109.47 mm |
| April | 15.3 °C | 25.2 °C | 125.48 mm |
| May | 19.6 °C | 28.9 °C | 142.49 mm |
| June | 22.7 °C | 31.4 °C | 191.52 mm |
| July | 23.6 °C | 32.3 °C | 210.06 mm |
| August | 23.4 °C | 32.6 °C | 192.79 mm |
| September | 21.6 °C | 30.7 °C | 144.27 mm |
| October | 16.1 °C | 27.1 °C | 103.38 mm |
| November | 10.5 °C | 22.1 °C | 97.54 mm |
| December | 7.6 °C | 18.6 °C | 108.71 mm |
| Annual | 15.6 °C | 25.6 °C | 1667.77 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 |