December in Santa Clarita is the coldest month of the year. In December, the weather in Santa Clarita is typically warm. Average daily high temperature in December is about 13 degrees above zero. On average, Santa Clarita has 20 sunny, 9 partly cloudy, and 2 rainy days in December. The rains are usually light. December as well as {{month_nom: February}}, and {{month_nom: February}} is considered the most uncomfortable time to visit Santa Clarita.