🌊 Level 5 Flood Warning for Shonai River

❓ What happened?

On September 8, 2026, Japan's Ministry of Land, Infrastructure, Transport and Tourism (MLIT) and the Japan Meteorological Agency (JMA) issued a Level 5 Flood Special Warning for the Shonai River, which flows through Aichi and Gifu prefectures. It means that, after the heavy rain up to that point, flooding had already occurred or was extremely likely to be occurring. For major nationally managed rivers, MLIT and JMA jointly issue Flood Forecasts in four stages: Flood Advisory, Flood Warning, Flood Danger Information, and finally the Flood Special Warning — the highest level. The crucial difference: the earlier stages are a forecast that danger is approaching, while Level 5 means disaster may already be happening and safe evacuation may no longer be possible. Level 5 is not a call to start evacuating; it is a call to take the best possible action to protect your life where you are. The details of the rainfall and points to note were published by MLIT's Water and Disaster Management Bureau and JMA as press material and reference material (both PDF).

👥 Who is affected?

• ●Foreign residents living in the Shonai River basin in Aichi and Gifu, including the Nagoya area
• ●People who work, study, or commute along the river
• ●Tourists and business travelers staying in the affected area
• ●Anyone living near the river, in low-lying land, or on a basement/first floor
• ●Anyone who finds Japanese disaster terminology hard to read and may miss evacuation information

🌏 Impact on foreign residents

Japanese disaster terms — advisory, warning, danger, special warning — look similar and are hard to tell apart in a hurry. But Level 5 is fundamentally different: it does not mean "start evacuating," it means "safe evacuation may no longer be possible." Misreading it can push people out onto flooded roads at the worst moment. In daily life, if you live in an apartment by the river or on a first floor or basement level, water can pour in through stairwells and parking areas very quickly. Commuting can break down as trains suspend service and roads go under water. Travelers, who have no sense of which land is low-lying, are safest following the instructions of their hotel staff. Evacuation shelters are open regardless of nationality or residence status — being a foreign national is never a reason to be turned away. Keep your residence card and passport together in a waterproof bag, since you will need them for procedures after evacuating.