The most pleasant months of the year for the 57197 zip code are June, August and September. In the 57197 zip code, there are 5 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for the 57197 zip code with an average high temperature of 83.6°, which ranks it as cooler than most places in South Dakota. December is the snowiest month in the 57197 zip code with 7.0 inches of snow, and 7 months of the year have significant snowfall. July is the most humid month, though humidity is low for most of the year.