Sebastian, Florida has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 19.1 °C (low) to 26.8 °C (high). Annual precipitation averages 1467.4 Millimeters. Sebastian is located in USDA Plant Hardiness Zone 10a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 12.3 °C | 21.7 °C | 71.88 mm |
| February | 13.6 °C | 22.8 °C | 71.88 mm |
| March | 15.7 °C | 24.3 °C | 81.03 mm |
| April | 18.4 °C | 25.9 °C | 71.12 mm |
| May | 21.1 °C | 27.8 °C | 100.33 mm |
| June | 23.2 °C | 29.8 °C | 193.8 mm |
| July | 23.7 °C | 31.9 °C | 173.23 mm |
| August | 24.2 °C | 30.7 °C | 211.58 mm |
| September | 23.9 °C | 30.2 °C | 198.37 mm |
| October | 21.9 °C | 28 °C | 141.73 mm |
| November | 17.1 °C | 25.7 °C | 83.31 mm |
| December | 14.4 °C | 23 °C | 69.09 mm |
| Annual | 19.1 °C | 26.8 °C | 1467.35 mm |
| Average First Frost Date | No Frost |
| Average Last Frost Date | |
| Average Days With Frost | Frost Free |
| Plant Hardiness Zone | Zone 10a : -1.1°C to 1.7°C |
| Plant Hardiness Zone - 2012 | Zone 10a : -1.1°C to 1.7°C |
| Current Drought Conditions | Normal |
| Köppen Climate Classification | Cfa - Humid Subtropical Climate |