With a population of around 8,200, Castle Shannon sits in Pennsylvania, United States. The city operates in the Eastern Time Zone.
In 2025, Castle Shannon recorded an average annual temperature of 52°F — right at the 30-year normal of 52°F. The hottest day reached 93°F in June; the coldest was -13°F in January. Total precipitation was 47 inches (wetter than usual). The wettest month was June.
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