Japanese
Home > Services > Monitoring of Earthquakes, Tsunamis & Volcanic Activity > Tsunami Warning/Advisory

Tsunami flags

Abstract

Since summer 2020, flags have been used in coastal areas to issue tsunami warnings/advisories (referred to here simply as "tsunami warnings").

Tsunami warnings are issued via TV, radio, mobile phones, disaster management radio, sirens, local alarms and other means. Visual notification using flags in coastal areas was also started in summer 2020 to help hearing-impaired people and swimmers, who may have difficulty hearing due to waves and wind. Immediate evacuation should follow any display of tsunami flags in coastal areas.

Tsunami flags

Tsunami flags feature a red and white checkered pattern, with a short side of 100 cm or more recommended for visibility. The flags have a design similar to that of the U-flag used internationally as a marine warning.

Tsunami flag

Tsunami flag

Evacuate immediately if you see a tsunami flag.

JMA YouTube video: Evacuate immediately if you see a tsunami flag.
For increased public awareness of tsunami flags (Japanese narration with English subtitles)
Produced in collaboration with the Japan Lifesaving Association

Display of a tsunami flag

Display of a tsunami flag
(Credit: Japan Lifesaving Association)

Video of a tsunami flag display (Japanese subtitles; 1 min.)
In collaboration with the Japan Lifesaving Association and Kanagawa Prefecture



Leaflet and poster