Lillian, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 15.1 °C (low) to 24.8 °C (high). Annual precipitation averages 1711 Millimeters. Lillian is located in USDA Plant Hardiness Zone 9a. The growing season typically runs from the last frost around Feb. 21 - Feb. 29 through the first frost around Dec. 1 - Dec. 10.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.7 °C | 16.1 °C | 143.51 mm |
| February | 7.4 °C | 18 °C | 121.92 mm |
| March | 10.7 °C | 21.1 °C | 131.57 mm |
| April | 14.6 °C | 24.3 °C | 146.56 mm |
| May | 18.9 °C | 28.2 °C | 100.08 mm |
| June | 22.7 °C | 30.9 °C | 166.12 mm |
| July | 23.6 °C | 31.9 °C | 187.2 mm |
| August | 23.6 °C | 31.9 °C | 184.91 mm |
| September | 21.3 °C | 30.2 °C | 172.47 mm |
| October | 15.8 °C | 26.2 °C | 106.43 mm |
| November | 9.9 °C | 21.3 °C | 117.35 mm |
| December | 6.7 °C | 17.4 °C | 132.84 mm |
| Annual | 15.1 °C | 24.8 °C | 1710.96 mm |
| Average First Frost Date | Dec. 1 - Dec. 10 |
| Average Last Frost Date | Feb. 21 - Feb. 29 |
| 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 |