The National Weather Service (NWS) is embarking on implementing a nation-wide plan to provide selected NWS offices with supplemental radar data from the Federal Aviation Administration’s (FAA’s) Terminal Doppler Weather Radar (TDWR) network. As part of a pilot program, the Baltimore-Washington DC Weather Forecast Office (WFO) located in Sterling, Virginia, has had access to real-time data access to the FAA’s TDWR that serves the Baltimore-Washington International (BWI) Airport. Operational characteristics of the TDWR system make it a useful supplement to the existing NWS/DOD network of NEXRAD WSR-88D radars. In particular, TDWR reflectivity data are provided at a high resolution, and the lowest elevation scanning angle operated by TDWRs typically provides lower (to the ground) coverage designed to identify microbursts.

This paper focuses on the various forecast uses of the TDWR data sets within an operational NWS-WFO environment based upon the experience of the Sterling WFO. Cases will be examined to illustrate how the TDWR data serves to augment existing NWS WSR-88D radar data in forecast applications in NWS marine, aviation, fire weather and public program areas, in addition to supplementing NWS severe weather operations.