On the verification of DWD's polarimetric hydrometeor classification and improved QPE

The weather radar network of the German weather service (DWD) consists of 17 C-Band weather radars (16 dual-polarisation and one single-polarisation). Beside the installation of the dual-polarisation systems (2010-2015), rework of existing and implementation of new algorithms was done. In this manner, methods for the estimation of the precipitation type (hydrometeor classification, Hymec) together with the amount of precipitation (quantitative precipitation estimation, QPE) were developed. These algorithms are in a technically operational status. They are included in an operational environment and process the radar measurements in a 24/7 scale. Though the proof of a technical stability is given, verification measures are needed to quantify the quality and operational usability of the derived products. In this paper, we focus on treating Hymec and QPE by verification with ground based meteorological measurement devices like disdrometers. An analysis was performed for different radar sites to get an impression for the whole German weather radar network. A weather event will help to highlight the verification measures. On the one hand, the verification results are intended to assist the users and on the other hand, the findings are useful for the optimisation of the algorithms.