April in Wausau is the windiest month of the year. In April, the weather in Wausau is typically warm. Average daily high temperature in April is about 12 degrees above zero. On average, Wausau has 10 rainy, 9 sunny, 7 partly cloudy, and 4 cloudy days in April. The rains are usually heavy. April as well as February, March, May, and October is considered the most uncomfortable time to visit Wausau.