Brunswick, Georgia has a Humid Subtropical Climate climate (Köppen classification: Cfa). Average annual temperatures range from 14.8 °C (low) to 25.2 °C (high). Annual precipitation averages 1257.8 Millimeters. Brunswick is located in USDA Plant Hardiness Zone 9a.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 5.2 °C | 16.8 °C | 90.68 mm |
| February | 6.7 °C | 18.4 °C | 80.52 mm |
| March | 9.9 °C | 21.6 °C | 93.73 mm |
| April | 14.1 °C | 25.1 °C | 74.68 mm |
| May | 18.4 °C | 28.7 °C | 70.87 mm |
| June | 22 °C | 31.4 °C | 160.02 mm |
| July | 23.3 °C | 33 °C | 128.02 mm |
| August | 23.2 °C | 32.2 °C | 169.42 mm |
| September | 21.3 °C | 29.9 °C | 160.02 mm |
| October | 16.2 °C | 26.1 °C | 114.3 mm |
| November | 10.6 °C | 21.6 °C | 49.28 mm |
| December | 7.1 °C | 18.1 °C | 66.29 mm |
| Annual | 14.8 °C | 25.2 °C | 1257.83 mm |
| Average First Frost Date | Frost Rare |
| Average Last Frost Date | |
| Average Days With Frost | Frost Rare |
| Plant Hardiness Zone | Zone 9a : -6.7°C to -3.9°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 |