August in Willow is the rainiest month of the year. In August, the weather in Willow is typically warm. Average daily high temperature in August is about 15 degrees above zero. On average, Willow has 17 rainy, 6 sunny, 5 cloudy, and 3 partly cloudy days in August. The rains are usually light. August as well as April, September, and October is considered the most uncomfortable time to visit Willow.