January in Surabaya is the rainiest and the cloudiest month of the year. In January, the weather in Surabaya is typically hot. Average daily high temperature in January is about 31 degrees above zero. On average, Surabaya has 30 rainy and 1 cloudy day in January. The rains are usually heavy. January as well as February, March, April, and May is considered the most uncomfortable time to visit Surabaya.