December in Reno is the coldest month of the year. In December, the weather in Reno is typically cold. Average daily high temperature in December is about 3 degrees above zero. On average, Reno has 16 partly cloudy, 10 sunny, 4 rainy, and 1 cloudy day in December. The rains are usually light. December as well as January and February is considered the most uncomfortable time to visit Reno.