The most pleasant months of the year for Winona are June, September and August. In Winona, there are 4 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for Winona with an average high temperature of 84.2°, which ranks it as one of the hottest places in North Dakota. March is the snowiest month in Winona with 9.2 inches of snow, and 8 months of the year have significant snowfall. There are few days during the summer when the humidity becomes unpleasant.