August in Warrnambool is the rainiest and the cloudiest month of the year. In August, the weather in Warrnambool is typically warm. Average daily high temperature in August is about 13 degrees above zero. On average, Warrnambool has 26 rainy, 3 sunny, and 2 cloudy days in August. The rains are usually heavy. August as well as May, June, July, and September is considered the most uncomfortable time to visit Warrnambool.