April in Glasgow is the sunniest month of the year. In April, the weather in Glasgow is typically cold. Average daily high temperature in April is about 9 degrees above zero. On average, Glasgow has 16 rainy, 6 sunny, 4 cloudy, and 4 partly cloudy days in April. The rains are usually light. April as well as January, February, March, and May is considered the most uncomfortable time to visit Glasgow.