Pennington, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 11.2 °C (low) to 24.7 °C (high). Annual precipitation averages 1474.2 Millimeters. Pennington is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 11 - Mar. 20 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 1.4 °C | 14.1 °C | 143 mm |
| February | 3.1 °C | 16.4 °C | 143 mm |
| March | 6.4 °C | 21 °C | 152.15 mm |
| April | 10.6 °C | 25.1 °C | 117.86 mm |
| May | 15.4 °C | 29 °C | 112.78 mm |
| June | 19.7 °C | 31.9 °C | 111.51 mm |
| July | 21.3 °C | 33.4 °C | 147.32 mm |
| August | 21.2 °C | 33.3 °C | 124.21 mm |
| September | 17.9 °C | 31.1 °C | 90.17 mm |
| October | 10.9 °C | 25.7 °C | 89.41 mm |
| November | 4.7 °C | 19.7 °C | 114.55 mm |
| December | 2.3 °C | 15.4 °C | 128.27 mm |
| Annual | 11.2 °C | 24.7 °C | 1474.23 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 11 - Mar. 20 |
| Average Days With Frost | 40-50 Days |
| Plant Hardiness Zone | Zone 8b : -9.4°C to -6.7°C |
| Plant Hardiness Zone - 2012 | Zone 8a : -12.2°C to -9.4°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |