Improved accuracy of radar WPMM estimated rainfall upon application of objective classification criteria

Application of the window probability matching method to radar and rain gauge data that have been objectively classified into different rain types resulted in distinctly different Z_e-R relationships for the various classifications. The classification parameters, in addition to the range from the radar, are 1) the horizontal radial reflectivity gradients [dB km^-1]; 2) the cloud depth, as scaled by the effective efficiency; 3) the brightband fraction within the radar field window; and 4) the height of the freezing level. Combining physical parameters to identify the type of precipitation and statistical relations most appropriate to the precipitation types results in considerable improvement of both point and areal rainfall measurements. -Authors