December in Cabo de Santo Agostinho is the sunniest month of the year. In December, the weather in Cabo de Santo Agostinho is typically hot. Average daily high temperature in December is about 29 degrees above zero. On average, Cabo de Santo Agostinho has 19 rainy, 6 sunny, 5 partly cloudy, and 1 cloudy day in December. The rains are usually moderate. December as well as January, February, March, and April is considered the most uncomfortable time to visit Cabo de Santo Agostinho.