In April, the weather in West Yellowstone is typically cold. Average daily high temperature in April is about 5 degrees above zero. On average, West Yellowstone has 11 partly cloudy, 7 sunny, 5 snowy, 4 cloudy, and 3 rainy days in April. The snowfalls are usually moderate. April as well as March, May, June, and October is considered the most uncomfortable time to visit West Yellowstone.