Precipitation rates from cloud systems can give a fundamental insight into the processes occurring in-cloud. While rain gauges and disdrometers can give information at a single point, remote sensors such as radars can provide rainfall information over a defined area.
The QPE value-added product (VAP) takes the Corrected Moments in Antenna Coordinates VAP and maps the Rain_rate_A field onto a Cartesian grid at the surface. This field is the rain rate as determined using the specific attenuation (A, dBZ/km) due to two-way liquid attenuation after Ryzhkov et al 2013. Since A is calculated using both differential phase and the integral of reflectivity along the beam path, it naturally combines a measurement sensitive to large and small rain rates as highlighted in a comparison against the Oklahoma Mesonet shown in Figure 1a. Figure 1b shows a single time step highlighting the ability of the algorithm to capture rainfall from both the leading convective line and the trailing stratiform region.