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Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first. Full disclaimer

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Japan alert decoder · 津波予報（若干の海面変動）

Tsunami Forecast (slight sea-level change)

Information · official rules as of 2026-10-17

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Information

津波予報（若干の海面変動）

Tsunami Forecast (slight sea-level change)

Sea level may change slightly (under 0.2 m). No damage is expected; take care if you are fishing or swimming.

What to do now

  1. No evacuation needed. Take care at the water's edge.

Issued by: JMA. Live status: JMA warnings map (English)JMA earthquake information (English)JMA tsunami information (English)

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Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first.

Data as of 2026-10-17 from official JMA, Cabinet Office, Cabinet Secretariat (J-ALERT) and Ministry of the Environment pages, with official names from the JMA multilingual dictionary (2026-03-26). Not affiliated with JMA or any government agency.

Educational guide, not an alert service: no live data. Always follow official instructions from JMA, your municipality, police, fire and staff. In an emergency, protect yourself first. Data as of 2026-10-17 from official JMA, Cabinet Office, Cabinet Secretariat (J-ALERT) and Ministry of the Environment pages, with official names from the JMA multilingual dictionary (2026-03-26). Not affiliated with JMA or any government agency.