In April, the weather in Barrie is typically warm. Average daily high temperature in April is about 10 degrees above zero. On average, Barrie has 10 sunny, 9 rainy, 7 cloudy, 3 partly cloudy, and 1 snowy day in April. The rains are usually heavy. April as well as March, October, November, and December is considered the most uncomfortable time to visit Barrie.