Zachary, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 13.9 °C (low) to 25.7 °C (high). Annual precipitation averages 1634 Millimeters. Zachary is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 11 - Feb. 20 through the first frost around Nov. 21 - Nov. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 4.7 °C | 16.4 °C | 169.16 mm |
| February | 6.5 °C | 18.7 °C | 134.11 mm |
| March | 9.9 °C | 22.4 °C | 121.41 mm |
| April | 13.4 °C | 25.8 °C | 129.54 mm |
| May | 17.9 °C | 29.4 °C | 148.08 mm |
| June | 21.6 °C | 32.3 °C | 168.15 mm |
| July | 22.7 °C | 33.1 °C | 137.16 mm |
| August | 22.4 °C | 33.4 °C | 147.07 mm |
| September | 19.9 °C | 31.4 °C | 116.33 mm |
| October | 13.9 °C | 26.8 °C | 122.43 mm |
| November | 8.4 °C | 21.3 °C | 103.12 mm |
| December | 5.6 °C | 17.5 °C | 137.41 mm |
| Annual | 13.9 °C | 25.7 °C | 1633.97 mm |
| Average First Frost Date | Nov. 21 - Nov. 30 |
| Average Last Frost Date | Feb. 11 - Feb. 20 |
| Average Days With Frost | 10-20 Days |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°C |
| Plant Hardiness Zone - 2012 | Zone 8b : -9.4°C to -6.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |