Applicability of flood forecasting for the next 72 hours in the northern Kyushu on July 2017

Abstract

In this study, we verified using WRF and RRI model for the purpose of clarifying whether the possibility of flooding could be detected several days ago. The predicted rainfall is calculated using WRF-LETKF by 33 ensemble members for the next 72 hours every 6 hours. The hydrological model used the RRI model, which has a spatial resolution of 2 seconds (50 meters) mesh.
At 9 o'clock on 4 July, 4 members predicted exceeding Evacuation W.L. of all 33 members, of which 2 members can predict Danger W.L.. At 115 o'clock on 4 July, 2 members predicted exceeding Evacuation W.L. of all 33 members, of which 1 members can predict Danger W.L..
Therefore, in this study, we found that it is possible to detect the possibility of flooding 21 hours ago by ensemble prediction.