The most pleasant months of the year for Rosemont are July, June and August. In Rosemont, there are 4 comfortable months with high temperatures in the range of 70-85°. August is the hottest month for Rosemont with an average high temperature of 81.6°, which ranks it as about average compared to other places in North Dakota. December is the snowiest month in Rosemont with 8.5 inches of snow, and 8 months of the year have significant snowfall. There are few days during the summer when the humidity becomes unpleasant.