A torrential downpour is when rain falls in a concentrated amount over a small area in a short period of time, and often occurs around the end of the rainy season.

A torrential downpour is considered to be a concentrated downpour when 50 mm or more of rain falls in one hour within an area several tens of kilometers in diameter.

Since it is easy for small and medium-sized rivers to overflow, mudslides, landslides, and other serious damage to occur, it is necessary to take extra precautions in built-up areas, fans, and near cliffs. In addition, torrential rains are extremely difficult to predict because they occur suddenly and unexpectedly over a small area.

Even in areas with relatively little rainfall, localized short-time torrential rains, such as intense rainfall exceeding 80 mm per hour, are on the increase, and such disasters may occur anywhere in the future. In order to be prepared for such an emergency, please use hazard maps to confirm hazardous areas and evacuation sites.

Warnings and advisories may be issued suddenly, so it is necessary to take safety measures as soon as possible by paying attention to weather information on the radio, TV, etc. and to the direction of rainfall. In particular, when an evacuation advisory or order is issued by the city or town, please evacuate immediately. However, if it becomes dangerous to go to an evacuation site due to flooding, one option is to evacuate to the second floor or higher of your home or a nearby tall building with a sturdy structure.