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Water temperatureEnter

South Korea: where to swim in October?

South Korea, in October: the sea is at 21.0 °C on average along the coast, from 19.0 °C to 23.0 °C depending on the spot. Where the water is warmest (23.0 °C), it is warm. Ideal for long swims and for being in the water all day.

Sea temperature, month by month

MonthAverage temperatureDepending on the spotWhere it is warmest
January12.3 °C7.3 °C – 16.4 °Ccool
February10.9 °C5.3 °C – 15.1 °Ccool
March10.9 °C6.2 °C – 14.7 °Ccold
April12.8 °C8.7 °C – 15.7 °Ccool
May15.6 °C13.4 °C – 17.5 °Ccool
June19.8 °C18.9 °C – 20.9 °Cpleasant
July23.2 °C22.0 °C – 25.1 °Cwarm
August26.2 °C25.3 °C – 27.6 °Cvery warm
September24.1 °C22.7 °C – 25.6 °Cwarm
October21.0 °C19.0 °C – 23.0 °Cwarm
November17.7 °C14.8 °C – 20.6 °Cpleasant
December14.9 °C10.8 °C – 18.6 °Ccool

Compared with September, the water cools down by 3.1 °C in October. The warmest month: August (26.2 °C). The coldest: February (10.9 °C).

Nearby, in October

And right now?

At sea, 21.4 °C on average across 53 stations, from 18.5 °C (Bouée ancrée 2200310) to 25.1 °C (Bouée ancrée 2200304). South Korea: water temperature

Frequently asked questions

What is the sea temperature in October?

South Korea, in October: 21.0 °C on average along the coast, from 19.0 °C in the coolest waters to 23.0 °C in the warmest (average of the years 2011 to 2025).

Can you swim in October?

Where the water is warmest (23.0 °C), it is warm. Ideal for long swims and for being in the water all day.

What is the best month for swimming?

The water is warmest in August (26.2 °C on average) and coldest in February (10.9 °C). Where the water is warmest, it goes above 20 °C in these months: June, July, August, September, October, November.

Where is the water warmest in October?

The warmest in October: Taiwan (27.0 °C), People's Republic of China (23.2 °C), Palau (29.5 °C). The coolest: Latvia (12.3 °C).

Where do these temperatures come from?

These are averages of the sea surface temperature from 2011 to 2025, computed from NOAA satellite images (OISST, one value about every 50 km), in a 100 km strip along the coasts of the main country: distant territories (overseas, remote islands) are not counted. It is an estimate, not a measurement taken at the beach: lakes and rivers are not included.

← September · November → · Warmest water today