January weather forecast in Siena

January in Siena is the cloudiest and the coldest month of the year. In January, the weather in Siena is typically cold. Average daily high temperature in January is about 7 degrees above zero. On average, Siena has 10 rainy, 8 sunny, 7 cloudy, and 6 partly cloudy days in January. The rains are usually heavy. January as well as February, March, November, and December is considered the most uncomfortable time to visit Siena.