FPUS46 KMTR 171141 City Forecast for Santa Rosa, CA Issued Tuesday morning - Sep 17, 2013 .Tuesday... Partly cloudy, high 76, 0% chance of precipitation. .Tuesday night... Low 53, 0% chance of precipitation. .Wednesday... Sunny, high 82, 0% chance of precipitation. .Wednesday night... Low 53. .Thursday... High 81.