Category: Cherry Blossom, Autumn Foliage, Weather, Fuji & Seasonal Timing · Tool #115 of 200
2026/2027 reference benchmarks
| Option / Scenario | 2026/2027 Benchmark |
|---|---|
| July – September (Water 28–29°C / 83°F · Rashguard only, peak tropical) | 28.5°C water |
| May – June & October (Water 25–27°C / 78°F · Warm swimming, fewer crowds) | 26°C water |
| April & November (Water 23–24°C / 74°F · Beach open, shorty wetsuit for long snorkel) | 23.5°C water |
| December – March (Water 21–22°C / 70°F · 3mm–5mm wetsuit required + whale watching) | 21.5°C water |
| Boat excursion + gear/wetsuit rental per day (¥) | 7,500 |
よくある質問（FAQ）
How does the Okinawa & Southern Islands Beach Opening, Wet-Suit Temperature & Snorkeling Season Calculator work?
Pick your scenario from the dropdown and enter your numbers—the calculator immediately computes your tailored result and compares it against water temp (°c/°f), wetsuit rule & excursion cost in JPY, USD, EUR, or GBP.
Are these 2026/2027 Japan figures and rules accurate?
Yes—all reference values are based on published 2026/2027 Japanese rail, ministry, weather, and retail benchmarks. Always confirm final seasonal schedules or rates with the official operator.
Can I share my exact calculation on Reddit or with travel companions?
Yes! Use the "Copy My Exact Result Link" or "Copy Reddit Markdown Table" button below the output to share your exact pre-filled scenario.
Can I embed this calculator on my blog or travel website?
Yes—copy the responsive iframe snippet in the Share & Embed box below at zero cost.