Cedar Key, Florida has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 17.3 °C (low) to 25.3 °C (high). Annual precipitation averages 1213.6 Millimeters. Cedar Key is located in USDA Plant Hardiness Zone 9b.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 8.6 °C | 17.5 °C | 95.25 mm |
| February | 10.3 °C | 19.1 °C | 69.85 mm |
| March | 13 °C | 21.6 °C | 87.12 mm |
| April | 16.8 °C | 24.8 °C | 71.12 mm |
| May | 20.5 °C | 28.2 °C | 50.04 mm |
| June | 23.8 °C | 30.4 °C | 133.86 mm |
| July | 24.7 °C | 31.1 °C | 181.36 mm |
| August | 24.7 °C | 31.2 °C | 225.81 mm |
| September | 22.9 °C | 30.2 °C | 129.29 mm |
| October | 18.6 °C | 27.1 °C | 65.53 mm |
| November | 13.4 °C | 22.7 °C | 41.4 mm |
| December | 10.5 °C | 19.1 °C | 62.99 mm |
| Annual | 17.3 °C | 25.3 °C | 1213.62 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 | Exceptional Drought |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |