May in Santo Domingo is the sunniest month of the year. In May, the weather in Santo Domingo is typically hot. Average daily high temperature in May is about 28 degrees above zero. On average, Santo Domingo has 27 rainy, 3 cloudy, and 1 sunny day in May. The rains are usually heavy. May as well as January, February, March, and April is considered the most uncomfortable time to visit Santo Domingo.