Belle Chasse, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 60.9 °F (low) to 78.4 °F (high). Annual precipitation averages 66.2 Inches. Belle Chasse is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 44.2 °F | 62.3 °F | 5.47 in. |
| February | 47.6 °F | 66.1 °F | 4.19 in. |
| March | 53.5 °F | 72.0 °F | 4.61 in. |
| April | 60.1 °F | 78.4 °F | 5.2 in. |
| May | 67.7 °F | 85.3 °F | 5.33 in. |
| June | 73.4 °F | 89.9 °F | 6.9 in. |
| July | 75.2 °F | 91.5 °F | 7.41 in. |
| August | 75.3 °F | 91.4 °F | 8.11 in. |
| September | 72.0 °F | 88.0 °F | 5.96 in. |
| October | 62.7 °F | 80.6 °F | 4.05 in. |
| November | 52.3 °F | 71.0 °F | 3.97 in. |
| December | 46.7 °F | 64.7 °F | 4.99 in. |
| Annual | 60.9 °F | 78.4 °F | 66.19 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 | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |