In January warmest sea in Japan is usually observed in the following locations: Okinawa, Nagasaki, Hakone.
Table below shows the average sea water temperature for marine resorts of Japan in January for the last three years.
| Place name | January 2026 | January 2025 | January 2024 |
|---|---|---|---|
| Okinawa | 72.4°F | 71.6°F | 72.8°F |
| Nagasaki | 62.9°F | 60.3°F | 60.6°F |
| Hakone | 61.9°F | 61.0°F | 62.0°F |
| Atami | 61.9°F | 61.1°F | 62.0°F |
| Kamakura | 61.1°F | 61.1°F | 62.1°F |
| Fukuoka | 58.6°F | 56.8°F | 57.8°F |
| Hiroshima | 58.1°F | 56.1°F | 57.0°F |
| Yokohama | 55.8°F | 55.9°F | 55.3°F |
| Nagoya | 55.7°F | 53.7°F | 55.8°F |
| Kobe | 55.2°F | 52.5°F | 53.8°F |
| Osaka | 55.1°F | 51.1°F | 53.7°F |
| Nara | 54.6°F | 51.1°F | 53.5°F |
| Kyoto | 53.5°F | 50.7°F | 53.0°F |
| Tokyo | 53.3°F | 52.9°F | 54.0°F |
| Noboribetsu | 45.2°F | 43.3°F | 42.2°F |
| Sapporo | 40.6°F | 41.6°F | 43.3°F |
Charts below show average sea water temperature for Japan resorts with the warmest sea in January.
You can also check other months of the year to see sea temperature of Japan resorts at that time.
Places in Japan:
Name
°F
