Lake Summerset, in Illinois, United States, is home to roughly 2,000 people in the Central Time Zone at 42.5°N latitude.
In 2025, Lake Summerset recorded an average annual temperature of 49°F — right at the 30-year normal of 49°F. The hottest day reached 93°F in June; the coldest was -11°F in January. Total precipitation was 29 inches (drier than usual). Snowfall totaled 10 inches, below the 37-inch average. The wettest month was July.
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