Taiwan — Sea Water Temperature and Annual Ranges

Sea Water Temperature Along the Coast

Places with the Warmest Sea Water Today

The Most Popular Seaside Places

Coastal Seas and Oceans

Water Temperature and Swimming Overview

Water Temperature Trends

Taiwan’s coastline experiences warm to mild sea temperatures year-round thanks to its subtropical to tropical location. Along the northern and western shores, winter surface temperatures typically fall to about 17–21°C (63–70°F), while the southern coasts around Kenting remain milder at roughly 22–25°C (72–77°F). Spring raises water into the low to mid 20s Celsius (about 72–79°F), and summer brings the warmest seas, often 27–30°C (81–86°F) or higher in shallow bays and lagoons. Autumn temperatures generally settle between 24–28°C (75–82°F). Regional variation is notable: offshore currents, depth, and local weather cause small but meaningful differences, with eastern and southern waters often the warmest and clearest.

Swimming Conditions

Swimming is widely permitted and popular at many of Taiwan’s beaches and reef areas, particularly in summer when lifeguards and safety flags are in place at designated bathing zones. The generally warm sea temperatures make snorkeling, diving and recreational swimming attractive for much of the year, especially in southern and offshore island locations where coral reefs thrive. However, visitors should heed seasonal hazards: the monsoon and typhoon season (roughly late spring through autumn) brings heavy rain, strong currents and occasional jellyfish blooms, and heavy rainfall can temporarily reduce water quality near river mouths. Local warnings, flagged beach systems and common-sense precautions are important for safe swimming, and water temperatures in the north during winter may feel cool to some swimmers.