Abstract
In recent years, the number of torrential rains that have caused devastating flooding and landslides has increased in Japan. At present, it is very difficult to predict heavy rainfall accurately. This has led to late issue of evacuation for local residents.
Rainfall intensity information using weather radar is difficult to detect the concentration of heavy rainfall in a specific area. For this reason, radar-based hourly rainfall is applied for early detection of heavy rainfall occurrence in this study.
Behavior of heavy rainfall is verified in two cases of heavy rain that occurred in Fukuoka on 21 July 2009 and in Hiroshima on 20 August 2014. In these cases, it was found that heavy rainfall areas were adjacent to disastrous areas before the occurrence of the disasters. It can also be expected that this radar information becomes one of important sources for early evacuation of local residents.
