In August, the weather in Oshkosh is typically warm. Average daily high temperature in August is about 25 degrees above zero. On average, Oshkosh has 17 sunny, 12 partly cloudy, and 2 rainy days in August. The rains are usually light. August as well as {{month_nom: February}}, and {{month_nom: February}} is considered the most comfortable time to visit Oshkosh.