December in Saint George is the coldest month of the year. In December, the weather in Saint George is typically cold. Average daily high temperature in December is about 9 degrees above zero. On average, Saint George has 16 sunny, 9 partly cloudy, 4 rainy, and 2 cloudy days in December. The rains are usually light. December as well as January and February is considered the most uncomfortable time to visit Saint George.