December weather forecast in Saint Marys

In December, the weather in Saint Marys is typically cold. Average daily high temperature in December is about 2 degrees above zero. On average, Saint Marys has 11 cloudy, 7 partly cloudy, 5 rainy, 5 snowy, and 3 sunny days in December. The rains are usually heavy. December as well as January, February, March, and April is considered the most uncomfortable time to visit Saint Marys.