With a population of around 13,000, Key Biscayne sits in Florida, United States. The city operates in the Eastern Time Zone.
In 2025, Key Biscayne recorded an average annual temperature of 77°F — right at the 30-year normal of 77°F. The hottest day reached 94°F in August; the coldest was 47°F in December. Total precipitation was 49 inches (drier than usual). The wettest month was September.
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