January in Cork is the sunniest month of the year. In January, the weather in Cork is typically cold. Average daily high temperature in January is about 8 degrees above zero. On average, Cork has 17 rainy, 6 sunny, 4 cloudy, and 4 partly cloudy days in January. The rains are usually heavy. January as well as February, March, April, and May is considered the most uncomfortable time to visit Cork.