About Long Lake, IL's Climate & Weather History

With a population of around 3,500, Long Lake sits in Illinois, United States. The city operates in the Central Time Zone.

In 2025, Long Lake recorded an average annual temperature of 50°F — about 1.3°F above the 30-year normal of 48°F. The hottest day reached 95°F in June; the coldest was -9°F in February. Total precipitation was 32 inches (drier than usual). The wettest month was July.