Warmest sea in South Korea in September

62 coastal locations in South Korea ranked by their typical September sea temperature. Region-wide average in September: 24.7°C. The top of the list is where to find the warmest swimming this month.

Warmest in September

Seogwipo

27.3°C September mean in South Korea

Regional September average

24.7°C

across all 62 coastal locations in South Korea

Vs annual mean

+7.5°C

above the year-round regional average

What the South Korea sea feels like in September

Water at this temperature is very pleasant to swim in. If you tend to wear a wetsuit when swimming, you might consider removing it now to avoid the body overheating.

South Korea monthly average 9.9°C to 26.2°C

Warmest month August 26.2°C
Coldest month February 9.9°C
Annual mean 17.1°C
Months above 20°C 4 of 12

Where September fits in the year

September sits inside the regional pattern shown on the left. Pick a different month to see how the ranking shifts.

All twelve South Korea month rankings:

South Korea sea temperature map (live)

The map shows today's latest reading at every South Korea location. The list below is based on the typical September mean, useful for trip planning weeks or months ahead.

Zoom in to see individual locations. Click a pin for water temperatures. View list →

°C -2 0 1 3 5 7 9 11 13 15 17 19 21 24 27 30 35

Top 50 warmest South Korea locations in September

Sorted by the typical September mean built from a decade of daily readings at each location. Click any place for its 30-day chart, monthly profile, and full 10-year history.

#	Location	Country	September mean
1	Seogwipo Jeju-do	South Korea	27.3°C
2	Hwasun Jeju-do	South Korea	27.2°C
3	Jukdo Jeju-do	South Korea	26.8°C
4	Udo Sudo Jeju-do	South Korea	26.5°C
5	Jeju	South Korea	25.8°C
6	Jejudo	South Korea	25.8°C
7	Chujado Jeju-do	South Korea	25.8°C
8	Gadeokdo Busan	South Korea	25.7°C
9	Jisepo Gyeongsangnam-do	South Korea	25.6°C
10	Busan	South Korea	25.6°C
11	Yokjido Gyeongsangnam-do	South Korea	25.4°C
12	Chinhae	South Korea	25.4°C
13	Masan	South Korea	25.4°C
14	Sinhyeon	South Korea	25.3°C
15	Ulsan	South Korea	25.3°C
16	Geoje	South Korea	25.3°C
17	Kyosai	South Korea	25.3°C
18	Geomundo Jeollanam-do	South Korea	25.3°C
19	Gwanyang Jeollanam-do	South Korea	25.2°C
20	Yeosu Jeollanam-do	South Korea	25.2°C
21	Cheongsando Jeollanam-do	South Korea	25.1°C
22	Wando Jeollanam-do	South Korea	25.1°C
23	Soando Jeollanam-do	South Korea	25.1°C
24	Reisui	South Korea	25.0°C
25	Narodo Jeollanam-do	South Korea	24.9°C

Show 25 more ▸

26	Gampo Gyeongsangbuk-do	South Korea	24.8°C
27	Geumdangdo Jeollanam-do	South Korea	24.8°C
28	Wido Jeollabuk-do	South Korea	24.8°C
29	Sunchun	South Korea	24.8°C
30	Ulleungdo Gyeongsangbuk-do	South Korea	24.6°C
31	Ansan	South Korea	24.5°C
32	Goyang	South Korea	24.5°C
33	Seoul	South Korea	24.5°C
34	Hwaseong	South Korea	24.4°C
35	Incheon	South Korea	24.4°C
36	Boryeong	South Korea	24.4°C
37	Kunsan	South Korea	24.4°C
38	Eocheongdo Jeollabuk-do	South Korea	24.2°C
39	Byeokpajin Jeollanam-do	South Korea	24.2°C
40	Eoranjin Jeollanam-do	South Korea	24.2°C
41	Modo Jeollanam-do	South Korea	24.2°C
42	Sangmado Jeollanam-do	South Korea	24.2°C
43	Daeyeonpyeongdo Incheon	South Korea	24.1°C
44	Ganggu Gyeongsangnam-do	South Korea	24.1°C
45	Hataedo Jeollanam-do	South Korea	24.1°C
46	Jukbyeon Gyeongsangbuk-do	South Korea	24.1°C
47	Taesal Li	South Korea	24.1°C
48	Daeheuksando Jeollanam-do	South Korea	23.9°C
49	Hoko	South Korea	23.8°C
50	Pohang	South Korea	23.8°C

Coldest 10 in South Korea in September

Same data the other way. Helpful if you want to know which South Korea coasts to avoid for swimming in September.

#	Location	Country	September mean
1	Sokcho	South Korea	22.8°C
2	Gangneung	South Korea	23.0°C
3	Yongpyong	South Korea	23.1°C
4	Baengnyeongdo Incheon	South Korea	23.1°C
5	Daecheongdo Incheon	South Korea	23.1°C
6	Tonghae	South Korea	23.3°C
7	Jumunjin Gangwon-do	South Korea	23.4°C
8	Mohang-ri Chungcheongnam-do	South Korea	23.6°C
9	Moppo	South Korea	23.7°C
10	Sinan	South Korea	23.7°C