In April, the weather in Bad Ischl is typically cold. Average daily high temperature in April is about 10 degrees above zero. On average, Bad Ischl has 22 rainy, 6 sunny, 1 cloudy, and 1 partly cloudy day in April. The rains are usually heavy. April as well as February, March, May, and June is considered the most uncomfortable time to visit Bad Ischl.