January in Lisbon is the rainiest, the cloudiest, and the coldest month of the year. In January, the weather in Lisbon is typically warm. Average daily high temperature in January is about 13 degrees above zero. On average, Lisbon has 11 rainy, 10 sunny, and 10 partly cloudy days in January. The rains are usually heavy. January as well as December is considered the most uncomfortable time to visit Lisbon.