Automating NEXRAD Data Use in GIS and Hydrologic and Hydraulic Applications Amit Sinha, Ph.D., Dean Djokic, Ph.D., Lori Armstrong Esri, Inc., Redlands, CA 92373
NEXRAD (Next-Generation Radar) is a network of over 140 radar towers spread nationwide and operated by the National Weather Service. These high resolution radars are used to measure atmospheric data such as reflectivity which can be processed to determine precipitation, and to monitor parameters indicating severe weather conditions. Geographical Information Systems (GIS) software is suitable for impact assessment from severe weather on lives and properties. GIS systems support a vast number of tools that can help us understand the spatial interaction between rainfall events and their respective impacts on areas of interest. However, ingesting NEXRAD efficiently into a GIS environment remains a challenge. There are few public domain tools available that make this job efficient. Many users download NEXRAD data from NWS web sites, and then curate it to use it for spatial analytics in a GIS environment. This is tedious and error prone. In the last few years, Unidata has provided real-time access to NEXRAD radar data, and the recent week's data is available through their website, though an automated way to import the data into a GIS environment remains an exercise. We present a framework that focuses on automating the ingestion of NEXRAD data stored in multiple formats, such as those provided by UNIDATA, in WaterML, and in NetCDF, into an ArcGIS geodatabase. We will also present an approach to use NEXRAD data in hydrologic and hydraulic analysis using public domain HEC suite of software applications to predict flooding events within GIS framework. Data from NEXRAD towers and watersheds in Texas are used to demonstrate the utility of the tools.