Warmest sea in Japan in December

373 coastal locations in Japan ranked by their typical December sea temperature. Region-wide average in December: 16.7°C. The top of the list is where to find the warmest swimming this month.

Warmest in December

Minami-Tori Shima

26.7°C December mean in Japan

Regional December average

16.7°C

across all 373 coastal locations in Japan

Vs annual mean

-2.4°C

below the year-round regional average

What the Japan sea feels like in December

At this temperature, water will feel cold compared to a swimming pool, but with a bit of experience and practice most people will find the water relatively comfortable to swim in.

Japan monthly average 12.8°C to 26.6°C

Warmest month August 26.6°C
Coldest month February 12.8°C
Annual mean 19.1°C
Months above 20°C 5 of 12

Where December fits in the year

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

All twelve Japan month rankings:

Japan sea temperature map (live)

The map shows today's latest reading at every Japan location. The list below is based on the typical December 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 Japan locations in December

Sorted by the typical December 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	December mean
1	Minami-Tori Shima Tokyo	Japan	26.7°C
2	lo Shima Tokyo	Japan	25.5°C
3	Yonakuni	Japan	25.4°C
4	Yonakuni Shima Okinawa	Japan	25.4°C
5	Kobi Sho Okinawa	Japan	25.1°C
6	Funauke Okinawa	Japan	25.0°C
7	Ishigaki	Japan	24.8°C
8	Hirara Okinawa	Japan	24.6°C
9	Miyakojima	Japan	24.6°C
10	Minami-Daito Shima Okinawa	Japan	24.5°C
11	Tsuhako Okinawa	Japan	24.3°C
12	Haha Shima Tokyo	Japan	24.2°C
13	Kerama Kaikyo (Zamami) Okinawa	Japan	24.2°C
14	Naha Ko Okinawa	Japan	24.2°C
15	Kanegusuku Okinawa	Japan	24.2°C
16	Haebaru	Japan	24.1°C
17	Itoman	Japan	24.1°C
18	Okinawa	Japan	24.1°C
19	Tomigusuku	Japan	24.1°C
20	Chichi Shima Tokyo	Japan	23.9°C
21	Chatan	Japan	23.9°C
22	Gushikawa	Japan	23.9°C
23	Suku Okinawa	Japan	23.9°C
24	Nakano Shima Kagoshima	Japan	23.8°C
25	Ogasawara	Japan	23.8°C

Show 25 more ▸

26	Wadomari Kagoshima	Japan	23.8°C
27	Toguchi Okinawa	Japan	23.7°C
28	Nago	Japan	23.7°C
29	Sanmura Wan Kagoshima	Japan	23.6°C
30	Amami	Japan	23.6°C
31	Koniya Kagoshima	Japan	23.6°C
32	Gakiya Okinawa	Japan	23.6°C
33	Takara Shima Kagoshima	Japan	23.6°C
34	Kasari Wan Kagoshima	Japan	23.4°C
35	Uken Kagoshima	Japan	23.4°C
36	Kuchi-No-Erabu Shima Kagoshima	Japan	23.3°C
37	Isso Kagoshima	Japan	22.8°C
38	Kumano Kagoshima	Japan	22.7°C
39	Tori Shima Tokyo	Japan	22.4°C
40	Hachijo Jima Tokyo	Japan	22.4°C
41	Yakushima	Japan	22.3°C
42	Miyake Shima Tokyo	Japan	21.8°C
43	Kozu Sima Tokyo	Japan	21.7°C
44	Nishinoomote	Japan	21.7°C
45	Aburatsu Miyazaki	Japan	21.4°C
46	Uchiumi Miyazaki	Japan	21.4°C
47	Miyazaki Shi	Japan	21.3°C
48	Shibushi	Japan	21.3°C
49	Makurazaki	Japan	21.2°C
50	Shikine Jima Tokyo	Japan	21.1°C

Coldest 10 in Japan in December

Same data the other way. Helpful if you want to know which Japan coasts to avoid for swimming in December.

#	Location	Country	December mean
1	Mombetsu	Japan	3.1°C
2	Abashiri Ko Hokkaido	Japan	3.2°C
3	Hojo	Japan	3.3°C
4	Monbetsu Hokkaido	Japan	3.5°C
5	Koiseboi Hokkaido	Japan	3.6°C
6	Shibetsu	Japan	3.8°C
7	Omu Ko Hokkaido	Japan	4.3°C
8	Moyoro Wan Hokkaido	Japan	4.5°C
9	Naibo Wan Hokkaido	Japan	4.8°C
10	Shana Wan Hokkaido	Japan	4.8°C