The most pleasant months of the year for the 62266 zip code are May, September and June. In the 62266 zip code, there are 2 comfortable months with high temperatures in the range of 70-85°. July is the hottest month for the 62266 zip code with an average high temperature of 88.8°, which ranks it as one of the hottest places in Illinois. January is the snowiest month in the 62266 zip code with 3.8 inches of snow, and 4 months of the year have significant snowfall. July is the most humid month, though humidity is low for most of the year.