Galliano, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 61.2 °F (low) to 77.9 °F (high). Annual precipitation averages 65 Inches. Galliano is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 44.2 °F | 63.0 °F | 5.45 in. |
| February | 48.1 °F | 66.4 °F | 3.77 in. |
| March | 53.8 °F | 71.8 °F | 4.17 in. |
| April | 60.8 °F | 77.3 °F | 4.83 in. |
| May | 68.3 °F | 83.9 °F | 4.79 in. |
| June | 73.3 °F | 88.6 °F | 7.72 in. |
| July | 74.5 °F | 89.9 °F | 7.79 in. |
| August | 74.8 °F | 90.3 °F | 7.91 in. |
| September | 71.9 °F | 87.1 °F | 6.4 in. |
| October | 63.8 °F | 80.3 °F | 4.39 in. |
| November | 53.4 °F | 71.4 °F | 3.42 in. |
| December | 47.2 °F | 65.0 °F | 4.31 in. |
| Annual | 61.2 °F | 77.9 °F | 64.95 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 |