In September, the weather in Belmont is typically warm. Average daily high temperature in September is about 20 degrees above zero. On average, Belmont has 15 sunny, 8 partly cloudy, 6 rainy, and 1 cloudy day 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 Belmont.