In September, the weather in Arcos de la Frontera is typically warm. Average daily high temperature in September is about 26 degrees above zero. On average, Arcos de la Frontera has 26 sunny, 3 rainy, and 1 partly cloudy day in September. The rains are usually moderate. September as well as May, June, and October is considered the most comfortable time to visit Arcos de la Frontera.