The most pleasant months of the year for Mussman are September, June and May. In Mussman, there are 2 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for Mussman with an average high temperature of 87.5°, which ranks it as warmer than most places in South Dakota. March is the snowiest month in Mussman with 9.3 inches of snow, and 7 months of the year have significant snowfall. There are few days during the summer when the humidity becomes unpleasant.