Fernandina Beach, Florida has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 16.5 °C (low) to 24.9 °C (high). Annual precipitation averages 1290.1 Millimeters. Fernandina Beach is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 7.2 °C | 17 °C | 91.44 mm |
| February | 8.7 °C | 18.3 °C | 83.82 mm |
| March | 11.7 °C | 21.2 °C | 81.03 mm |
| April | 15.7 °C | 24.4 °C | 76.71 mm |
| May | 19.8 °C | 27.8 °C | 70.61 mm |
| June | 23.1 °C | 30.6 °C | 159.26 mm |
| July | 24.2 °C | 31.9 °C | 137.41 mm |
| August | 24.1 °C | 31.4 °C | 152.15 mm |
| September | 22.9 °C | 29.7 °C | 184.15 mm |
| October | 18.4 °C | 26.1 °C | 121.92 mm |
| November | 12.8 °C | 21.6 °C | 49.02 mm |
| December | 9.3 °C | 18.3 °C | 82.55 mm |
| Annual | 16.5 °C | 24.9 °C | 1290.07 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9b : -3.9°C to -1.1°C |
| Plant Hardiness Zone - 2012 | Zone 9a : -6.7°C to -3.9°C |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |