WSR-88D Dual Polarization Background and Status
The NWS Statement of Need 04-004 (Additional Radar Observational Data)
identified the NWS need for additional and improved radar data to improve
support to severe weather warnings, flood and flash flood warnings, and
general forecast services.
The NEXRAD tri-agencies (DOC, DOD, DOT) have determined that adding Dual Polarization
capability to the WSR-88D will provide mission benefits that aid in meeting the NWS
Government Performance and Results Act. These benefits include improved hail detection
for severe thunderstorm warnings, improved rainfall estimation for flood and flash
flood warnings, rain/snow discrimination for winter weather warnings and advisories, data
retrieval from areas of partial beam blockage to improve services in mountainous terrain, and
removal of non-weather artifacts such as birds and ground clutter to improve overall data
quality for algorithms and numerical model input.
In the spring of 2003 the National Weather Service (NWS) Office of Science and
Technology (OST) tasked the National Severe Storms Laboratory (NSSL) with providing
data collection and analysis to support a WSR-88D dual polarization decision
briefing to the NEXRAD Program Management Committee (NPMC). The JPOLE (Joint
Polarization Experiment) project was designed to evaluate the engineering design
and data quality of the polarimetric KOUN WSR-88D radar and demonstrate the
utility of polarimetric radar data and products to operational users. The NSSL
JPOLE experiment demonstrated the performance improvements dual polarization
provided in rainfall estimates, hydrometeor classification, and general data
quality. For more general information on JPOLE and polarmetric radars
go to: http://www.nssl.noaa.gov/dualpol/.
A competitive Firm Fixed Price Contract was awarded to L3
Communications (teamed with Baron Services & Essco) on
September 24, 2007 for the upgrade of the WSR-88D Weather
Radars with Dual Polarization capability.
The deployment of the Dual Polarization modification
to “single-thread” sites (one RDA per site) is underway. See the “Deploy Schedule”
and “Deployment Status” sections of this web site located at:
for further information/details.
The development of the Dual Polarization modification
for “dual-thread sites (two RDAs per site) is in progress. Deployment of
the modification to field sites should start in 2013.