Three-dimensional Gridding and Mosaic of Reflectivities from Multiple WSR-88D Radars

The deployment of the NEXRAD network has provided information critical for issuing severe storm warnings, flash flood warnings, and mesoscale nowcasting to forecasters. Currently the operational radar data are processed for individual radars and most of the algorithms applied to these data use the radar information in polar coordinates. This approach limits the usefulness of the NEXRAD network to problems that do not require multiple radar observations. However, there are many problems that require observations from multiple radars or from radars and other ground-based, airborne, and spaceborne data sources, e.g., many severe storm and flash flood monitoring situations, regional aviation controls, and numerical weather prediction. Gridded and mosaicked radar data are necessary for applications like these.

An adaptive, Barnes-type objective analysis has been used to interpolate data from multiple radars onto a common Cartesian grid. It is shown to provide fine resolution 3D reflectivity analysis with high computational efficiency. Various WSR-88D users could benefit from a wide-variety of products and displays (flexible horizontal or vertical cross-sections and regional rainfall are examples) that could be extracted easily from multiple radar analysis grids. Gridded radar data can also be easily combined with information from other data sources (e.g., satellite, gridded model analyses or forecast fields) increasing its value in the overall forecast and warning process. Results from several winter and summer cases will be shown at the conference.