April in Bozeman is the rainiest month of the year. In April, the weather in Bozeman is typically cold. Average daily high temperature in April is about 7 degrees above zero. On average, Bozeman has 14 rainy, 7 sunny, 6 partly cloudy, and 3 cloudy days in April. The rains are usually moderate. April as well as March and May is considered the most uncomfortable time to visit Bozeman.