NEXRAD-ITR: Developing a framework for use of NEXRAD data in hydrology and hydrometeorology

We are developing and implementing a scientific workflow for producing surface rainfall maps suitable for research in hydrology and hydrometeorology that include the following steps: AP/clutter detection and removal, reflectivity-rainfall transformation, and georeferencing and transformation from polar coordinates to surface coordinates such as latitude/longitude, HRAP, and others. We are currently ingesting the full resolution (Archive Level II) data from 30 radars in real time via the UCAR/Unidata Internet Data Distribution. Core metadata are extracted and managed in a relational database as the data are ingested. The real-time data are augmented with selected data from NCDC's archive. We follow a watershed-centric approach so that user can request surface rainfall estimates for a watershed(s), which may require the mosaicing of estimates from several radars, but this is handled in a transparent manner by the system. Using a web browser users can select an output coordinate system, a watershed, time period, and desired temporal resolution. The system will then produce rainfall maps using predefined or user-selected algorithms in netCDF and other formats. A web services interface allows programmatic access to the system via scripts or compiled programs from remote servers. The completed system will be able to serve up watershed-centric maps rainfall maps that span multiple years. We will make the data and services available to the community via CUAHSI, NCDC, and Unidata.