January in Leiria is the rainiest and the coldest month of the year. In January, the weather in Leiria is typically warm. Average daily high temperature in January is about 12 degrees above zero. On average, Leiria has 14 rainy, 11 sunny, and 6 partly cloudy days in January. The rains are usually heavy. January as well as February is considered the most uncomfortable time to visit Leiria.