Donaldsonville, Louisiana has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 14.6 °C (low) to 25.8 °C (high). Annual precipitation averages 1634.2 Millimeters. Donaldsonville 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 Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.6 °C | 16.8 °C | 147.57 mm |
| February | 7.4 °C | 18.9 °C | 110.24 mm |
| March | 10.7 °C | 22.5 °C | 107.44 mm |
| April | 13.9 °C | 25.7 °C | 128.52 mm |
| May | 18.4 °C | 29.3 °C | 150.62 mm |
| June | 21.9 °C | 31.9 °C | 180.34 mm |
| July | 23.1 °C | 32.7 °C | 160.27 mm |
| August | 22.8 °C | 33 °C | 174.5 mm |
| September | 20.7 °C | 31.2 °C | 132.33 mm |
| October | 14.8 °C | 27.1 °C | 113.54 mm |
| November | 9.2 °C | 21.8 °C | 104.9 mm |
| December | 6.6 °C | 18.1 °C | 123.95 mm |
| Annual | 14.6 °C | 25.8 °C | 1634.22 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| 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 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |