Japan alert decoder · レベル5高潮特別警報
Level 5 Emergency Warning (Storm Surge) · Level 5
Act now: protect yourself · official rules as of 2026-10-17
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レベル5高潮特別警報
Level 5 Emergency Warning (Storm Surge)
Black, Alert Level 5 equivalent: a disaster is probably already happening or imminent. Your life is in danger. Hazard: sea water flooding the coast during a typhoon or deep low. Since 2026-05-29 the Level 5 storm-surge warning is issued when flooding is happening or imminent.
What to do now
- Take the safest action you can right now; it may be too late to go to a shelter.
- If going outside is dangerous: go to an upper floor (flooding, storm surge) or a room on the side away from the slope (landslide).
- Evacuation should already have happened at Level 4; don't wait for Level 5.
- Stay away from the coast, harbours and low coastal land.
- Japan's rule of thumb: evacuate by Level 4 (purple). Don't wait for Level 5.
Issued by: JMA. Live status: JMA warnings map (English)JMA earthquake information (English)JMA tsunami information (English)
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.