Performance analysis of the Italian radar QPE

The Italian weather radar network, currently composed by 21 systems, is managed by a federation of national and regional bodies including the Department of Civil Protection (DPC), the regional weather services, the Air Force and the National Aviation Authority. In total 14 radars out of 21 are dual-polarized. The DPC, currently managing 6 C-band and 2 X-band polarimetric systems, collects and processes the data provided by every network partner to generate and distribute national-level products. The rainfall products are mainly used for monitoring purposes within the national early-warning system. The intrinsic uncertainties related to the radar rainfall estimation and the network heterogeneity encouraged the design and implementation of an approach for the evaluation of radar data quality to be used as weighting parameter for the generation of composite products. This work describes the current status of the network, in terms of algorithms, data quality control and operational performance. It is shown, on one side, that the use of polarimetric approaches has remarkably improved the overall rainfall retrieval performance, on the other, that orography and the heterogeneity of the radar systems are the main factors affecting the estimate uncertainty. The seasonal dependency and sensitivity of the QPE with respect to the data quality are also sho