NEXRAD Product Improvement – Update 2014

The NEXRAD tri-agencies (Department of Commerce, National Weather Service (NWS); the Department of Defense, Air Force Weather Agency; the Department of Transportation, Federal Aviation Administration (FAA)) established the NEXRAD Product Improvement (NPI) Program as a long-term activity to steadily improve WSR-88D science and technology. In June 2013, the NPI program completed deployment of the dual polarization upgrade throughout the WSR-88D network, which promises to vastly improve rainfall estimates, hydrometeor classification and overall data quality. The dual polarization deployment concluded the formal NPI Program, which started in 1997, delivering Open Systems RPG, then ORDA, and many data quality and radar meteorological algorithm improvements and additions.

As the NWS gains experience with the WSR-88D dual polarization products, it's clear that the initial algorithms need tuning to address performance issues seen in certain geographic and climatic regions, and that much more operational benefit can be realized by infusing additional radar science and signal processing technology. NWS funding constraints have sharply reduced NPI resources, which has reduced the scope and speed at which algorithms and technology can be infused into the WSR-88D. However, steady progress continues at a reduced capacity and scope.

In addition to WSR-88D efforts, the NPI program integrated weather data from several FAA radar systems into NWS operational use. Data from all 45 Terminal Doppler Weather Radar (TDWR) units are used to generate WSR-88D type products to provide supplemental low altitude coverage and tornado detection, as well as enhanced WSR-88D back-up operations. On the horizon are potential projects for short wavelength, boundary layer radars to improve low altitude tornado detection and to support storm scale NWP models. A bit further out is the potential for incorporation of Phased Array Antenna technology, with its promise of comprehensive, rapid scanning surveillance.

This paper updates the status of radar product improvement projects, describes recent science and technology enhancements to the WSR-88D, and explores the expanding opportunities for development and implementation of new radar science and techniques intended to use WSR-88D and FAA weather radar data.