Swimming in South Korea in september 2025 Sea temperature by city in september

Do you want to go to the beach in South Korea in september 2025? Is it the right month to go for pleasant temperatures and staying in the water for a long time? The answer is on this page with the sea temperatures in september in South Korea by city and our opinion on the chances of enjoying pleasant sea conditions.

Sea temperature in South Korea in september 2025

Here, find the average sea temperature in South Korea in september in several coastal cities.

Direct access: South in september | Northeast in september | North West in september | East in september | West in september

South in september

Busan

on average:

77°F

min: 73°F / max: 81°F

Jeju Island (Jejudo)

on average:

77°F

min: 74°F / max: 80°F

Namhae

on average:

76°F

min: 72°F / max: 80°F

Tongyeong

on average:

77°F

min: 72°F / max: 81°F

Ulsan

on average:

76°F

min: 72°F / max: 80°F

Yeosu

on average:

76°F

min: 72°F / max: 80°F

Northeast in september

Gangneung

on average:

72°F

min: 67°F / max: 77°F

Sokcho

on average:

71°F

min: 66°F / max: 76°F

North West in september

Incheon

on average:

72°F

min: 69°F / max: 75°F

Ansan-si

on average:

72°F

min: 69°F / max: 75°F

Hwaseong-si

on average:

72°F

min: 69°F / max: 75°F

East in september

Pohang

on average:

75°F

min: 72°F / max: 79°F

Gyeongju

on average:

75°F

min: 72°F / max: 78°F

Uljin

on average:

72°F

min: 67°F / max: 77°F

West in september

Gunsan

on average:

73°F

min: 69°F / max: 77°F

Share on facebook Share on twitter Send on messenger Send by email

Sea temperature in august in South Korea

Sea temperature in october in South Korea

Where should you go swimming in South Korea in the month of september?

Swimming in South Korea in september is pleasant

In september in South Korea swimming conditions are generally the same everywhere.

As for Busan, Jeju Island (Jejudo), Gangneung, Incheon, Pohang, Sokcho, Gyeongju, Namhae, Tongyeong, Uljin, Ulsan, Yeosu, Ansan-si, Gaigeturi, Goseong, Gunsan, Haenam, Hwaseong-si, Jangan, Moppo, Muan, Oepo and Seogwipo, swimming is pleasant in september. The sea water is 77°F on average (min: 73°F/max: 81°F) so you can easily spend time in the water.

Where to go swimming in South Korea in september: the map of sea temperatures

ideal swimming

pleasant swimming

cool swimming

cold swimming

freezing swimming

Water temperature and seasonal norms in september

Busan

	August	September	October
Average sea temperature	80°F	77°F	73°F
Minimum sea temperature	77°F	73°F	69°F
Maximum sea temperature	83°F	81°F	77°F
Average outside temperature	81°F	76°F	67°F
Maximum outside temperature	85°F	77°F	70°F
Minimum outside temperature	77°F	72°F	63°F
Precipitation	7.5in	6in	2.9in
Number of days of precipitation	9 jour(s) (30%)	6 jour(s) (19%)	2 jour(s) (8%)
Cloud cover	37%	39%	28%
Our opinion	ideal swimming	pleasant swimming	pleasant swimming

More information on swimming in Busan in september

Jeju Island (Jejudo)

	August	September	October
Average sea temperature	80°F	77°F	72°F
Minimum sea temperature	74°F	74°F	67°F
Maximum sea temperature	85°F	80°F	76°F
Average outside temperature	81°F	76°F	67°F
Maximum outside temperature	85°F	77°F	70°F
Minimum outside temperature	77°F	72°F	65°F
Precipitation	10.9in	11.3in	6in
Number of days of precipitation	9 jour(s) (30%)	8 jour(s) (28%)	4 jour(s) (12%)
Cloud cover	40%	46%	37%
Our opinion	ideal swimming	pleasant swimming	pleasant swimming

More information on swimming in Jeju Island (Jejudo) in september

Gangneung

	August	September	October
Average sea temperature	76°F	72°F	67°F
Minimum sea temperature	72°F	67°F	62°F
Maximum sea temperature	80°F	77°F	72°F
Average outside temperature	76°F	68°F	59°F
Maximum outside temperature	81°F	74°F	65°F
Minimum outside temperature	68°F	61°F	54°F
Precipitation	9.6in	8.2in	4.4in
Number of days of precipitation	11 jour(s) (35%)	7 jour(s) (22%)	3 jour(s) (11%)
Cloud cover	39%	35%	28%
Our opinion	pleasant swimming	pleasant swimming	cool swimming

More information on swimming in Gangneung in september

Incheon

	August	September	October
Average sea temperature	75°F	72°F	66°F
Minimum sea temperature	70°F	69°F	61°F
Maximum sea temperature	79°F	75°F	70°F
Average outside temperature	81°F	74°F	63°F
Maximum outside temperature	86°F	79°F	68°F
Minimum outside temperature	77°F	68°F	59°F
Precipitation	12.8in	6.2in	3in
Number of days of precipitation	11 jour(s) (36%)	5 jour(s) (16%)	3 jour(s) (10%)
Cloud cover	40%	32%	25%
Our opinion	pleasant swimming	pleasant swimming	cool swimming

More information on swimming in Incheon in september

Pohang

	August	September	October
Average sea temperature	77°F	75°F	71°F
Minimum sea temperature	74°F	72°F	68°F
Maximum sea temperature	80°F	79°F	74°F
Average outside temperature	79°F	72°F	63°F
Maximum outside temperature	85°F	77°F	68°F
Minimum outside temperature	76°F	68°F	58°F
Precipitation	8.2in	7.7in	5in
Number of days of precipitation	8 jour(s) (27%)	6 jour(s) (19%)	3 jour(s) (11%)
Cloud cover	40%	40%	30%
Our opinion	pleasant swimming	pleasant swimming	pleasant swimming

More information on swimming in Pohang in september

List of coastal cities in South Korea

Busan in september	pleasant swimming
Jeju Island (Jejudo) in september	pleasant swimming
Gangneung in september	pleasant swimming
Incheon in september	pleasant swimming
Pohang in september	pleasant swimming
Sokcho in september	pleasant swimming
Gyeongju in september	pleasant swimming
Namhae in september	pleasant swimming
Tongyeong in september	pleasant swimming
Uljin in september	pleasant swimming
Ulsan in september	pleasant swimming
Yeosu in september	pleasant swimming
Ansan-si in september	pleasant swimming
Gaigeturi in september	pleasant swimming
Goseong in september	pleasant swimming
Gunsan in september	pleasant swimming
Haenam in september	pleasant swimming
Hwaseong-si in september	pleasant swimming
Jangan in september	pleasant swimming
Moppo in september	pleasant swimming
Muan in september	pleasant swimming
Oepo in september	pleasant swimming
Seogwipo in september	pleasant swimming