Heavy rain information changed starting the FY2026 flood season. A new “Urgent Warning” has been added, one that didn’t exist before, and information names now carry an Alert Level number.
If you learned the old “three-tier” system of advisory, warning, and emergency warning, it’s worth checking your understanding again.
The current correspondence table
Here is how the Japan Meteorological Agency (JMA) maps its disaster prevention weather information to Alert Levels.
| JMA information | Kikikuru color | Alert Level | Evacuation info issued by the municipality |
|---|---|---|---|
| Level 5 Emergency Warning | Disaster Imminent (black) | Equivalent to Alert Level 5 | Emergency Safety Measures |
| Level 4 Urgent Warning | Danger (purple) | Equivalent to Alert Level 4 | Evacuation Instruction |
| Level 3 Warning | Alert (red) | Equivalent to Alert Level 3 | Evacuation for Elderly and Others |
| Level 2 Advisory | Caution (yellow) | Level 2 | — |
| Early Warning Information (possibility of warning-level phenomena) | — | Level 1 | — |
What’s new is the “Level 4 Urgent Warning.” JMA describes it as “information that serves as a benchmark for the local municipality to issue a Level 4 Evacuation Instruction” — it corresponds to the stage where evacuation from a dangerous location is necessary.
The terms “Advisory” and “Warning” are still in use, but now think of it this way: Warning = Level 3, Urgent Warning = Level 4.
Kikikuru shows danger as colors on a map
Kikikuru is a map that displays the risk of heavy-rain disasters as an area. JMA evaluates how rainfall behaves using three indices.
- Soil Water Index — how much rain has soaked into and accumulated in the ground → Landslide Kikikuru
- Surface Water Index — how easily rain pools on the surface → Inundation Kikikuru
- Runoff Index — how much rain has gathered into rivers and is flowing down → Flood Kikikuru
Together with Heavy Rain Kikikuru, four types are provided in total. JMA explains that using these indices lets it assess and judge rising disaster risk more appropriately than rainfall amount alone.
Think of it not as “how many millimeters per hour,” but as a tool for seeing where that rain is having an effect right now — that’s enough to use it. You only need to check the color over your own address.
The color categories were also reorganized on 30 June 2022: “Disaster Imminent” (black) was added, and “Very Dangerous” (light purple) and “Extremely Dangerous” (dark purple) were merged into a single “Danger” (purple). Older explanations may still show two shades of purple.
Kikikuru also has a push notification service. As with registering for power outage information, registering after the rain has already started is too late.
The single most important point: you don’t have to wait
What this article most wants you to take away isn’t the details of the table — it’s this.
JMA states plainly:
In many cases, disaster prevention weather information is issued before the municipality issues an evacuation instruction or similar order.
And when information equivalent to Alert Level 4 or 3 is issued:
Even if an evacuation instruction has not been issued, use Kikikuru, river water level information, and similar sources to make your own decision to evacuate.
You do not need to wait for an evacuation instruction. A municipality’s order does not always come first. Checking whether you’re in a landslide warning zone in advance is partly so that you have the material to make that judgment yourself when this moment comes.
You don’t have to commit to a pre-designated evacuation site, either
There’s another piece of guidance that’s not widely known. On evacuating, JMA states:
Rather than insisting on heading to a pre-designated evacuation site, it is important to take whatever safety action is best at that moment based on your own judgment — for example, evacuating to the upper floor of a sturdy nearby building, even a small distance away from a river or cliff.
If the designated shelter is far away and the road there is dangerous, don’t force your way to it. As covered in Evacuation Sites and Shelters Are Different, evacuating doesn’t mean “going to a designated building” — it means moving to a place that can protect your life.
What to watch for in Okinawa
In Okinawa, heavy rain often arrives together with a typhoon, which is exactly where judgment can get tangled.
- If wind is the main threat — going outside is more dangerous. Staying inside is the basic rule
- If landslide or inundation risk is the main threat — staying in that location is the danger. Leave early
Tell which situation you’re in by the Kikikuru color, and whether your home is in a warning area. When in doubt, err on the side of safety.
Note that it is the municipality that issues evacuation information corresponding to Alert Levels 3, 4, and 5. What that means and how to act on it is also covered in Evacuating on an Island, Staying in Touch Off-Island (Japanese only). In case a power outage takes out both TV and internet, keep a battery-powered radio on hand as an information source.
What this article does not cover
This site does not cover which warnings, advisories, or Kikikuru levels are currently in effect. Always check JMA’s latest information yourself for the current colors.
This article does not make the decision of whether to evacuate for you. Follow JMA and your municipality’s information, and err on the side of safety when in doubt.
Information names and operations are subject to further revision. This article reflects the system in place as of the FY2026 flood season.