December in Lubbock is the coldest month of the year. In December, the weather in Lubbock is typically cold. Average daily high temperature in December is about 10 degrees above zero. On average, Lubbock has 19 sunny, 11 partly cloudy, and 1 rainy day in December. The rains are usually moderate. December as well as January is considered the most uncomfortable time to visit Lubbock.