Best Dive Spots for New Year's Diving in Japan — Data-Driven Visibility Rankings

March 11, 2026 · Based on December–January real observation data

New Year's Is Actually a Golden Season for Diving

The idea that 'winter is bad for diving' is a misconception. Analyzing December and January data, many sites record their highest or near-highest annual visibility during this period. With low plankton and stable Kuroshio current, winter is actually one of Japan's best diving seasons from a visibility standpoint. We rank the best spots for New Year's diving using real observation data.

New Year's Visibility Rankings — Top 10

Ranked by average December–January visibility from real observations

Rank	Site	Region	Dec	Jan	Avg	Temp
1	Yonaguni	Okinawa	23.4m	22.4m	22.9m	24.6°C
2	Amami Oshima	Kagoshima	24.6m	22.7m	23.8m	21.4°C
3	Ishigaki	Okinawa	19.4m	20.9m	19.9m	—
4	Ito	Chiba	18.7m	18.8m	18.7m	17.5°C
5	Kerama	Okinawa	18.5m	18.1m	18.3m	22.5°C
6	IOP	Shizuoka	17.3m	18.6m	17.9m	17.9°C
7	Hachijojima	Tokyo	16.8m	17.4m	17.2m	20°C
8	Kashiwajima	Kochi	16.3m	16.8m	16.5m	19°C
9	Futo	Shizuoka	15m	15.6m	15.3m	17.2°C
10	Mikomoto	Shizuoka	13.7m	13.6m	13.7m	17.9°C

Sites with fewer observations (Amami, Ishigaki etc.) should be treated as indicative.

December or January — Which Is Better?

Site	Dec	Jan	Trend
Amami	24.6m	22.7m	Dec peak
Yonaguni	23.4m	22.4m	Dec slightly better
Ishigaki	19.4m	20.9m	Jan improves
Ito	18.7m	18.8m	Nearly identical
Kerama	18.5m	18.1m	Dec slightly better
IOP	17.3m	18.6m	Big Jan improvement
Hachijo	16.8m	17.4m	Jan improves
Futo	15m	15.6m	Jan improves

Overall, Okinawa sites (Yonaguni, Kerama) favor December slightly, while Izu sites (IOP, Futo) tend to improve toward January. Ishigaki is notable for being better in January than December.

Notable Sites: Detailed Analysis

Top: Yonaguni (22.9m) & Amami Oshima (23.8m)

Yonaguni consistently records 22–23m throughout December and January. Notably, Amami Oshima shows a remarkable 24.6m in December (though with only 147 observations — treat as indicative). Less famous than Yonaguni, Amami may actually beat it for year-end clarity. Water temperatures above 21°C eliminate the need for a drysuit.

Hidden Gem: Ito (Chiba, 18.7m)

Ito in Tateyama, Chiba shows a very stable 18.7m during the New Year period. Accessible from Tokyo in 2–3 hours by car, it's an uncrowded hidden gem. A drysuit is recommended at 16–17°C water temperature, but visibility slightly exceeds IOP (17.9m). Highly recommended for Kanto-based divers wanting to end or start the year near home.

Izu Representative: IOP (17.9m)

IOP (Izu Oceanic Park) records 18.6m in January — its annual visibility peak. It leads all 6 Izu Peninsula sites for New Year visibility, and is only about 2 hours from Tokyo by express train. Water temperatures around 17–18°C mean most divers wear drysuits, though experienced divers can manage with thick wetsuits.

For Hammerheads: Mikomoto (13.7m)

Ranking 10th on visibility at 13.7m, but midwinter is peak season for hammerhead shark aggregations at Mikomoto. Conditions are reasonable at ~14m visibility, but strong currents and cold water (16–17°C) make it an advanced site. Choose Mikomoto only if you have the specific goal of seeing hammerheads during the New Year period.

Summary: Choose Sites That Benefit from Winter Conditions

Choose based on your budget, travel time, and goals. For maximum visibility: Yonaguni or Amami. For value near Tokyo: Ito or IOP. For a combined Okinawa trip: Kerama or Ishigaki. The data shows that New Year's diving aligns with — or is close to — each site's annual visibility peak. Far from being a waste, it's one of the year's best times to dive in Japan.

Data source: scraped from public dive logs. December and January observations aggregated. Sites with few observations should be treated as indicative.