December in Hawaii offers a generally pleasant tropical climate, though variations exist across the islands and elevations. Expect daytime temperatures averaging in the mid-70s Fahrenheit (low 20s Celsius) at sea level, with cooler conditions at higher altitudes. Rainfall increases during this period, marking the beginning of the wetter season, and ocean temperatures are typically comfortable for swimming.
Understanding typical December conditions is crucial for planning activities and packing appropriately for a Hawaiian vacation. Historical weather data provides a helpful guide for anticipating potential conditions, enabling visitors to make informed choices regarding outdoor excursions, beach time, and island exploration. This awareness contributes to a more enjoyable and potentially safer experience, minimizing disruptions caused by unexpected weather shifts.