FPUS42 KJAX 291455 City Forecast for Brunswick, GA Issued Tuesday morning - Nov 29, 2016 .Tuesday... Partly cloudy, high 79, 10% chance of precipitation. .Tuesday night... Low 65, 5% chance of precipitation. .Wednesday... Partly cloudy, high 79, 10% chance of precipitation. .Wednesday night... Low 62. .Thursday... High 68.