When To Go · Destination Guide
Yonaguni
Oceanic drift diving, seasonal hammerheads and a puzzling submerged rock formation at Japan's western edge.
When To Go · Destination Guide
Oceanic drift diving, seasonal hammerheads and a puzzling submerged rock formation at Japan's western edge.
When to go
A March-April stay offers a defensible compromise for sea and land, but there is no reliably calm all-island dive season.
Best overall window
Spring transition: seasonal shark opportunity persists while days are generally more comfortable for outdoor touring; windy boat days still occur.
Outside that window
Spring transition: seasonal shark opportunity persists while days are generally more comfortable for outdoor touring; windy boat days still occur.
Start with the overall answer, then switch only when scuba, freedive, snorkel, or topside timing changes the trip in a meaningful way.
The overall row stays visible so you can compare it against the currently selected scope.
| Scope | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Overall | Overall - Jan: Tradeoffs | Overall - Feb: Tradeoffs | Overall - Mar: Best | Overall - Apr: Best | Overall - May: Tradeoffs | Overall - Jun: Tradeoffs | Overall - Jul: Tradeoffs | Overall - Aug: More variable | Overall - Sep: More variable | Overall - Oct: More variable | Overall - Nov: Good | Overall - Dec: Tradeoffs |
These do not replace the overall planner. Use them only if a specific animal or event is driving your trip dates.
Hammerhead shark search at Irizaki
Best for Scuba
Dec to Apr
Seasonal local boat-diving focus.
Warm-season reef fish and rocky topography
Best for Scuba
May to Nov
Local operators market guided alternative drift, reef and sand dives outside the main shark focus; this is not a predictable biological spawning event or proof of calm seas.
Yonaguni international marlin-fishing competition
Best for Topside
Jul
An annual calendar listing, not a confirmed 2027 date or an invitation to take marine wildlife.
Yonaguni island road-running event
Best for Topside
Nov
The tourism association lists an annual island marathon-style event in November.
Built from climate references, access rules, and destination operators. Wildlife timing and route flexibility can shift year to year.