The most pleasant months of the year for Olivia are June, August and July. In Olivia, there are 4 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for Olivia with an average high temperature of 82.2°, which ranks it as about average compared to other places in North Dakota. January is the snowiest month in Olivia with 9.0 inches of snow, and 8 months of the year have significant snowfall. There are few days during the summer when the humidity becomes unpleasant.