Opp, Alabama has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 12.9 °C (low) to 25.6 °C (high). Annual precipitation averages 1532.6 Millimeters. Opp is located in USDA Plant Hardiness Zone 8b. The growing season typically runs from the last frost around Mar. 1 - Mar. 10 through the first frost around Nov. 11 - Nov. 20.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 3.1 °C | 15.9 °C | 131.83 mm |
| February | 4.9 °C | 18.3 °C | 126.24 mm |
| March | 8.3 °C | 22.1 °C | 140.21 mm |
| April | 12 °C | 25.8 °C | 119.63 mm |
| May | 16.7 °C | 29.8 °C | 108.71 mm |
| June | 20.7 °C | 32.4 °C | 151.64 mm |
| July | 22.1 °C | 33.4 °C | 170.18 mm |
| August | 21.8 °C | 33.1 °C | 138.18 mm |
| September | 19.3 °C | 31.3 °C | 118.62 mm |
| October | 13.2 °C | 26.6 °C | 93.47 mm |
| November | 7.3 °C | 21.1 °C | 109.47 mm |
| December | 4.8 °C | 17.1 °C | 124.46 mm |
| Annual | 12.9 °C | 25.6 °C | 1532.64 mm |
| Average First Frost Date | Nov. 11 - Nov. 20 |
| Average Last Frost Date | Mar. 1 - Mar. 10 |
| Average Days With Frost | 30-40 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 |