January in Los Alamos is the coldest month of the year. In January, the weather in Los Alamos is typically cold. Average daily high temperature in January is about 1 degree above zero. On average, Los Alamos has 14 partly cloudy, 10 sunny, 5 rainy, and 2 cloudy days in January. The rains are usually light. January as well as February, November, and December is considered the most uncomfortable time to visit Los Alamos.