Extreme rain events analysis using X-band weather radar

Abstract

The X-band radar installed in Turin was used to analyze extreme events. About 3 years of radar maps have been analyzed in comparisons with about 30 years of measurements made by rain gauges located in the same area. The entire monitored area was divided into 4 subareas considering the complex orography near Turin, namely the flatlands, mountains, hills and urban areas. For each subarea, the Generalized Extreme Values (GEV) distributions are estimated considering rain gauges data and X-band radar maps. Radar maps are properly processed to be comparable with rain gauges measurements considering reference areas of different size centered over each available gauge. It is shown that a limited temporal availability of X-band radar maps can be sufficient to obtain a good GEV distribution estimation, and that X-band weather radars are a good instrument to analyze extreme rain events where a dense rain gauge network is not available.