Structure and Evolution of Precipitation Cores in an Isolated Convective Storm Observed by Phased Array Weather Radar

摘要

A phased array weather radar (PAWR) can complete one volume scan in 30 s, thus enabling us to obtain high spatiotemporal resolution echo intensities and wind fields of storms. Using its rapid scanning capability, we investigated the evolution of a convective storm in detail. To describe the evolution of convective storms, we used the following definitions. The precipitation cell is defined as a three-dimensionally contiguous region of 40 dBZ or greater. The precipitation core is defined by a threshold of positive deviation greater than 7 dBZ, which is a difference from the average reflectivity during the mature stage of the cell. An updraft core is defined as an updraft region of 1 m s ?1 or stronger at a height of 2 km.