January in Haddington is the rainiest and the coldest month of the year. In January, the weather in Haddington is typically cold. Average daily high temperature in January is about 5 degrees above zero. On average, Haddington has 24 rainy, 4 cloudy, and 3 sunny days in January. The rains are usually moderate. January as well as February, March, April, and May is considered the most uncomfortable time to visit Haddington.