April in Winona is the windiest month of the year. In April, the weather in Winona is typically warm. Average daily high temperature in April is about 14 degrees above zero. On average, Winona has 11 rainy, 9 sunny, 7 partly cloudy, and 3 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 Winona.