January in Gagny is the coldest month of the year. In January, the weather in Gagny is typically cold. Average daily high temperature in January is about 5 degrees above zero. On average, Gagny has 15 rainy, 9 cloudy, 4 sunny, and 3 partly 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 Gagny.