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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 · 南海トラフ地震臨時情報（調査中）

Nankai Trough Earthquake Extra Information (Under Analysis)

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南海トラフ地震臨時情報（調査中）

Nankai Trough Earthquake Extra Information (Under Analysis)

Something unusual (for example an M6.8+ quake) happened in or near the Nankai Trough area (the Pacific coast from Shizuoka to Kyushu), and experts are checking whether a megaquake has become more likely. Issued 5-30 minutes after the event; the result comes at the earliest about 2 hours after the quake.

What to do now

  1. Get ready to evacuate quickly if you are in a tsunami area.
  2. Watch for the next update: 巨大地震警戒, 巨大地震注意 or 調査終了.

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.