Japanese emergency alerts — the names changed in May 2026, and the three most serious never say special warning

In an emergency, go to the agency, not to this page. Everything below is an explanation of official terms with links to the people who issue them. Every instruction quoted is theirs, not ours, and what an official on the spot tells you comes first.

⭐ The names changed on 29 May 2026

Japan's weather warnings for river flooding, heavy rain, landslides and storm surge were renamed so that each one now carries its alert level in the name. 大雨警報 became レベル３大雨警報 — "Level 3 Heavy Rain Warning". A new tier, レベル４危険警報 ("Level 4 Danger Warning"), sits where there was previously a scatter of separately-named bulletins.

The reason given is that the correspondence between warnings and the five evacuation levels had become too complicated to act on. The practical consequence for a visitor: an English explanation written for the old system — a plain "heavy rain warning", with no level — describes names that are no longer issued. Earthquake early warnings and tsunami warnings kept their names.

The five levels

⚠ The weather information usually arrives before the municipality issues anything. The agency says so, and tells people not to wait for the municipal instruction before deciding to leave. It also says not to insist on reaching a designated shelter: an upper floor of a nearby solid building, away from a river or a slope, may be the better choice at the time.

⛔ Three special warnings that never say "special warning"

The advice you will read in English is to watch for a "special warning", the top tier. For the three fastest-moving hazards in Japan that advice will never fire, because those special warnings keep their ordinary names:

The agency puts it plainly: these special warnings are issued under their existing names, without the words. A Major Tsunami Warning is the special warning for a tsunami.

What the earthquake warning does not tell you

Two omissions catch people, and the agency explains both:

• It does not say how strong the shaking will be where you are. The estimate carries about ±1 of error on the intensity scale, so it says "strong shaking" instead.
• It does not say how many seconds you have. The areas it names are each roughly a third or a quarter of a prefecture, and the answer differs a lot across one.

⛔ And the top tier is not announced differently. An Earthquake Early Warning predicting intensity 6-lower or above is legally a special warning, but the agency states that it cannot be distinguished from an ordinary one in the seconds available — so it is not. The alert you hear is the same either way.

It fires when two or more stations have registered the waves and the strongest shaking is predicted at intensity 5-lower or above, or long-period ground motion class 3 or above. Two stations, to avoid a false alarm from something like a lightning strike right next to a single seismometer. Areas expecting only intensity 4 are named too — the estimate may be low, and the rupture may still be growing.

Heat is a different agency and a different scale

Heat alerts come from the Ministry of the Environment, are measured on WBGT rather than air temperature, and sit outside the five-level system entirely. A Heat Stroke Alert is issued when the forecast daily maximum WBGT reaches 33 at any one observation point in the area, for today or tomorrow. A Heat Stroke Special Alert is issued, among other conditions, when tomorrow's forecast reaches 35 at every observation point in the prefecture — dangerous heat over a wide area without precedent — and asks organizers to consider calling events off.

Where to look, in order

The one most visitors do not know exists is Safety tips, an app supervised by the Japan Tourism Agency. It pushes earthquake early warnings, tsunami warnings, weather special warnings and more in 15 languages, drawing on the government's multilingual dictionary of about 7,000 terms — a dictionary published for broadcasters and app makers rather than for reading.

Related

• Peak season checker — typhoon season overlaps the busiest travel weeks.
• Trip checklist — what else your dates decide.