April in Roslyn is the cloudiest month of the year. In April, the weather in Roslyn is typically warm. Average daily high temperature in April is about 14 degrees above zero. On average, Roslyn has 11 rainy, 8 sunny, 8 partly cloudy, and 3 cloudy days in April. The rains are usually heavy. April as well as January, February, March, and November is considered the most uncomfortable time to visit Roslyn.