Making NEXRAD Precipitation Data Available to the Hydrology Community


October 6, 2005


Tomislav Urban


University of Texas at Austin


Next Generation Doppler Radar (NexRad) has enabled the possibility of collecting high-resolution precipitation data across the country that is of high value to hydrologists studying, amongst other things, flooding, evaporation, and drought. These data however, available only is non-standard, binary, formats, and in file structures not conducive to the types of queries typically performed in the domain, have been difficult to integrate easily into the hydrologist’s research. For example, whereas a hydrologist may seek to obtain data for a single variable over a small geographical entity for a fairly significant temporal extent on the order of months or years; the files on the other hand are typically available for one hour periods extending over a large region or even over the entire country. Since the level of IT support for these researchers can be low, this has presented an impediment to the ready access to NexRad data. This project seeks to provide simple web application- and web service-based access to these data in whatever spatial and temporal extents are most convenient to the user. By storing the data in SQL Server, we are able to quickly generate output files for precisely the variables, geographies, times and formats that are required. Additionally, as we are using the ArcHydro schema developed by out partners at the Center for Research in Water Resources (CRWR) also at the University of Texas; the data can be easily output as geo-referenced points or polygons allowing the user to bring to bear an array of GIS-based analytic tools already generally available. Looking ahead, we see this collection growing into a major repository of hydrology-related data including stream and rain gauge point data and water quality.


Tomislav Urban

Urban is currently Manager of the Data and Information Systems group at the Texas Advanced Computing Center. He has worked at TACC for three years, focusing on database and scientific data collections issues. Prior to TACC, Urban worked for several years as an application and database architect in the private sector.