April in Milwaukee is the rainiest month of the year. In April, the weather in Milwaukee is typically cold. Average daily high temperature in April is about 10 degrees above zero. On average, Milwaukee has 14 rainy, 7 cloudy, 5 sunny, and 4 partly cloudy days in April. The rains are usually heavy. April as well as March, May, November, and December is considered the most uncomfortable time to visit Milwaukee.