Regional Application of a Dual Polarization Qauntitative Precipitation Estimation System Over the Pigeon River Basin

Dual polarization weather radar measurements provide additional capabilities to improve estimates of rainfall rate and accumulation versus traditional reflectivity methodology. The ability of radar to measure over broad spatial areas in short temporal successions encourages its application for rainfall estimation, where radar reflectivity-rainfall (Z-R) relations have been traditionally used to derive quantitative precipitation estimation (QPE). The purpose of this paper is to present the evaluation of a regional dual polarization QPE system using the dual polarization radar rain rate estimation algorithms developed at Colorado State University. Radar input can be ingested from NEXRAD radar network as well as other regional radars where the requirement is for the radar to have polarimetric capability. The individual radar data are processed to generate QPE. Once the individual rainfall maps are generated, they are fused into common coordinates using data fusion principles to create a single QPE product covering the domain of interest.

This implementation and evaluation in this study will consider the rainfall events that occurred during the National Aeronautics and Space Administration (NASA) Global Precipitation Measurement (GPM) ground validation field campaign (GVFC) that was conducted during the Integrated Precipitation and Hydrology Experiment (IPHEx) in the southern Appalachian Mountains from May 1 to June 15, 2014, where the goal is to further quantify the capability of dual polarization radar data on QPE performance in orographic regions. This domain is situated over a complex terrain environment, such that local radar coverage and QPE is compromised by blockage, beam overshooting effects, orographic precipitation enhancement and unique climatic conditions. This area of interest is concentrated around the Pigeon River Basin near Asheville, NC.