In September, the weather in Lake Ozark is typically warm. Average daily high temperature in September is about 25 degrees above zero. On average, Lake Ozark has 22 sunny, 5 rainy, and 3 partly cloudy days in September. The rains are usually heavy. September as well as {{month_nom: February}}, and {{month_nom: February}} is considered the most comfortable time to visit Lake Ozark.