CORRELATION ANALYSIS BETWEEN STORM EVENTS AND METEOROLOGICAL CONDITIONS

Abstract

This study aims to determine the most dominant meteorological factors for extreme precipitation, such as probable maximum precipitation (PMP); this is important in determining the conditions that generate extreme events to understand their magnitude. This study analyzed historical heavy rainfall events and their corresponding meteorological factors. The factors considered in this study are precipitable water (PW), surface dew point (SDT), temperature, relative humidity (RH), convective available potential energy (CAPE), and vertical wind velocity (VVEL) in eight different regions in Japan. To collect sufficient data, we utilized reanalysis data from “Japanese 55-year Reanalysis” (JRA-55), and the relation between historical rainfall events and the selected factors was analyzed via the cumulative density function (CDF) exceeding 0.95. In southern Japan, the VVEL and PW were highly correlated factors for historical events. In northern Japan, PW was the highest correlated factor for the events. Conversely, temperature had the lowest extreme ratio in all areas. Based on this analysis, we can conclude that PMP estimation via PW is reasonable for these areas.