In December, the weather in Arcos de la Frontera is typically warm. Average daily high temperature in December is about 17 degrees above zero. On average, Arcos de la Frontera has 13 sunny, 8 rainy, 8 partly cloudy, and 2 cloudy days in December. The rains are usually moderate. December as well as January, July, and August is considered the most uncomfortable time to visit Arcos de la Frontera.