NEXRAD Dual Polarization Data for FAA Aviation Products

The entire NEXRAD network of 160 radars has been operating with a dual polarization capability since the latter half of 2013. The initial capability includes the Hydrometeor Classification Algorithm (HCA) that estimates the bulk scatterers contributing to the radar returns. HCA along with new dual pol parameters contributes to on-going efforts to develop and/or improve weather radar products for FAA weather systems. Broadly, the focus is to improve data quality, enhance detection of wind shear features, and detect new aviation weather hazards. MIT Lincoln Laboratory has developed dual-pol-based icing hazard and hail hazard products that are now deployed in the network with an initial operational capability. Those two products are based on interpretation of particular classifications from HCA augmented with meteorological model data within the NEXRAD Radar Product Generator.

Currently, MIT Lincoln Laboratory continues the development and testing of advanced dual-pol-based concepts – now moving beyond HCA classifications - to improve upon the hazard detection algorithms, data quality approaches, and wind shear detection algorithms. This includes expanded area coverage of the icing hazard product, incorporation of hail sizing, improving removal of non-weather returns, mitigation of partial beam blockage, and enhancing detection of dry microbursts. A key challenge is the proper interpretation of the dual pol data within these automated algorithms (no human-in-the-loop). Additional challenges are the calibration/consistency of the dual pol data as well as validation/verification of HCA classifications and algorithm products. The more promising concepts will be discussed in relation to the challenges encountered with a look forward to the future expectations from the products.