Westwego, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 16.5 °C (low) to 25.8 °C (high). Annual precipitation averages 1672.1 Millimeters. Westwego is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.1 °C | 16.8 °C | 140.72 mm |
| February | 9 °C | 18.9 °C | 107.7 mm |
| March | 12.4 °C | 22.4 °C | 115.82 mm |
| April | 16.2 °C | 25.8 °C | 123.44 mm |
| May | 20.4 °C | 29.7 °C | 138.43 mm |
| June | 23.5 °C | 32.3 °C | 186.44 mm |
| July | 24.6 °C | 33.1 °C | 193.8 mm |
| August | 24.4 °C | 33 °C | 187.96 mm |
| September | 22.7 °C | 31.1 °C | 145.54 mm |
| October | 17.6 °C | 26.9 °C | 97.79 mm |
| November | 12 °C | 21.7 °C | 102.87 mm |
| December | 8.6 °C | 18.2 °C | 131.57 mm |
| Annual | 16.5 °C | 25.8 °C | 1672.08 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 9b : -3.9°C to -1.1°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |