March in Milford Sound is the sunniest month of the year. In March, the weather in Milford Sound is typically warm. Average daily high temperature in March is about 12 degrees above zero. On average, Milford Sound has 18 rainy, 8 sunny, 4 partly cloudy, and 1 cloudy day in March. The rains are usually heavy. March as well as January, February, April, and May is considered the most uncomfortable time to visit Milford Sound.