NOAA NEXt-Generation RADar (NEXRAD) Products

Description

This dataset consists of Level III weather radar products collected from Next-Generation Radar (NEXRAD) stations located in the contiguous United States, Alaska, Hawaii, U.S. territories and at military base sites. NEXRAD is a network of 160 high-resolution Doppler weather radars operated by the NOAA National Weather Service (NWS), the Federal Aviation Administration (FAA), and the U.S. Air Force (USAF). Doppler radars detect atmospheric precipitation and winds, which allow scientists to track and anticipate weather events, such as rain, ice pellets, snow, hail, and tornadoes, as well as some non-weather objects like birds and insects. NEXRAD stations use the Weather Surveillance Radar - 1988, Doppler (WSR-88D) system. This is a 10 cm wavelength (S-Band) radar that operates at a frequency between 2,700 and 3,000 MHz. The radar system operates in two basic modes: a slow-scanning Clear Air Mode (Mode B) for analyzing air movements when there is little or no precipitation activity in the area, and a Precipitation Mode (Mode A) with a faster scan for tracking active weather. The two modes employ nine Volume Coverage Patterns (VCPs) to adequately sample the atmosphere based on weather conditions. A VCP is a series of 360 degree sweeps of the antenna at pre-determined elevation angles and pulse repetition frequencies completed in a specified period of time. The radar scan times 4.5, 5, 6 or 10 minutes depending on the selected VCP. During 2008, the WSR-88D radars were upgraded to produce increased spatial resolution data, called Super Resolution. The earlier Legacy Resolution data provides radar reflectivity at 1.0 degree azimuthal by 1 km range gate resolution to a range of 460 km, and Doppler velocity and spectrum width at 1.0 degree azimuthal by 250 m range gate resolution to a range of 230 km. The upgraded Super Resolution data provides radar reflectivity at 0.5 degree azimuthal by 250 m range gate resolution to a range of 460 km, and Doppler velocity and spectrum width at 0.5 degree azimuthal by 250 m range gate resolution to a range of 300 km. Super resolution makes a compromise of slightly decreased noise reduction for a large gain in resolution. In 2010, the deployment of the Dual Polarization (Dual Pol) capability to NEXRAD sites began with the first operational Dual Pol radar in May 2011. Dual Pol radar capability adds vertical polarization to the previous horizontal radar waves, in order to more accurately discern the return signal. This allows the radar to better distinguish between types of precipitation (e.g., rain, hail and snow), improves rainfall estimates, improves data retrieval in mountainous terrain, and aids in removal of non-weather artifacts. The NEXRAD products are divided in two data processing levels. The lower Level II data are base products at original resolution. Level II data are recorded at all NWS and most USAF and FAA WSR-88D sites. From the Level II quantities, computer processing generates numerous meteorological analysis Level III products. The Level III data consists of reduced resolution, low-bandwidth, base products as well as many derived, post-processed products. Level III products are recorded at most U.S. sites, though non-US sites do not have Level III products. There are over 40 Level III products available from the NCDC. General products for Level III include the base and composite reflectivity, storm relative velocity, vertical integrated liquid, echo tops and VAD wind profile. Precipitation products for Level III include estimated ground accumulated rainfall amounts for one and three hour periods, storm totals, and digital arrays. Estimates are based on reflectivity to rainfall rate (Z-R) relationships. Overlay products for Level III are alphanumeric data that give detailed information on certain parameters for an identified storm cell. These include storm structure, hail index, mesocyclone identification, tornadic vortex signature, and storm tracking information. Radar messages for Level III are sent by the radar site to users in order to know more about the radar status and special product data. NEXRAD data are provided to the NOAA National Climatic Data Center for archiving and dissemination to users. Data coverage varies by station and ranges from May 1992 to 1 day from present. Most stations began observing in the mid-1990s, and most period of records are continuous.

Resources

Name Format Description Link
0 Landing page for the dataset. https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncdc:C00682/html
0 Informational resources for NEXRAD Radar Data. https://www.ncei.noaa.gov/products/radar/next-generation-weather-radar
0 Search the data archive to submit an order via the interface or download files if available. https://www.ncei.noaa.gov/access/search/data-search/weather-radar-level-ii
0 Search the data archive to submit an order via the interface or download files if available. https://www.ncei.noaa.gov/access/search/data-search/weather-radar-level-iii
0 Dynamic GIS mapping application to locate stations and data for selected layers. https://www.ncei.noaa.gov/maps/radar/
0 Search for radar data and estimated VCP mode by station ID, location, and date via a text-based interface. https://www.ncdc.noaa.gov/nexradinv/
23 ArcGIS Server REST API for the dataset. https://gis.ncdc.noaa.gov/arcgis/rest/services/cdo/nexrad/MapServer
51 Web Feature Service for the dataset. https://gis.ncdc.noaa.gov/arcgis/services/cdo/nexrad/MapServer/WFSServer?request=GetCapabilities&service=WFS
25 Direct download link for KMZ file. https://gis.ncdc.noaa.gov/kml/nexrad.kmz
0 Informational resources for NEXRAD Radar Data. https://www.ncdc.noaa.gov/data-access/radar-data/nexrad
0 NCEI home page with information, data access and contact information. https://www.ncei.noaa.gov
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords. https://earthdata.nasa.gov/about/gcmd/global-change-master-directory-gcmd-keywords
0 The Interface Control Documents (ICDs) describe the data format specification for multiple WSR-88D Build Versions. https://www.roc.noaa.gov/WSR88D/BuildInfo/Files.aspx
33 Document includes WSR-88D system concepts, terminology and acronyms. https://www.ofcm.gov/publications/fmh/FMH11/2016FMH11PTA.pdf
33 Document provides a background in doppler radar meteorology. https://www.ofcm.gov/publications/fmh/FMH11/fmh-11B-2005.pdf
33 Document provides a full description of the WSR-88D meteorological and hydrological products and algorithms. https://www.ofcm.gov/publications/fmh/FMH11/fmh11partC.pdf
33 Document provides an overview of unit operations and functional flow and insights into the meteorological applications of the WSR-88D. https://www.ofcm.gov/publications/fmh/FMH11/FMH11D-2006.pdf
0 AMS Journal Publication. https://doi.org/10.1175/1520-0477%281993%29074%3C1669%3ATWATWO%3E2.0.CO%3B2
0 AMS Journal Publication. https://doi.org/10.1175/1520-0434%281998%29013%3C0219%3AHOOUOW%3E2.0.CO%3B2
0 AMS Journal Publication. https://doi.org/10.1175/1520-0434%281998%29013%3C0244%3AHOOUOW%3E2.0.CO%3B2
52 Web Map Service for the dataset. https://gis.ncdc.noaa.gov/arcgis/services/cdo/nexrad/MapServer/WMSServer?request=GetCapabilities&service=WMS
0 Information on free visualization, analysis, and decoding tools for the radar data format. https://www.ncei.noaa.gov/products/radar/radar-display-conversion-tools
0 Level-III NEXRAD data are 40+ products generated from NEXRAD Level-II data using computer algorithms at the radar sites and include base and composite reflectivity, precipitation estimates, storm relative velocity, vertical integrated liquid, hail index, tornadic vortex signature, mesocyclone identification, and echo tops along with the dual-polarization measurements of differential reflectivity, correlation coefficient and specific differential phase, hydrometer classification, and melting layer data. https://www.ncei.noaa.gov/metadata/geoportal/rest/metadata/item/gov.noaa.ncdc:C00345/html

Tags

  • tornados
  • yellow sea
  • vertical location
  • human dimensions
  • wind direction
  • precipitation
  • united states of america
  • weather stations/networks
  • western pacific ocean
  • spectrum width
  • land surface
  • north pacific ocean
  • northern hemisphere
  • national climatic data center
  • nesdis
  • doppler velocity
  • national geospatial data asset
  • hurricanes
  • wind dynamics
  • precipitation amount
  • radar cross-section
  • east china sea
  • snow
  • okinawa
  • atmosphere
  • tropical cyclones
  • continent
  • typhoons
  • noaa
  • guam
  • radar sounders
  • weather events
  • caribbean sea
  • azores
  • weather/climate advisories
  • eastern asia
  • severe weather
  • hydrological advisories
  • troposphere
  • north america
  • earth science services
  • sensor characteristics
  • weather stations
  • atlantic ocean
  • gulf of alaska
  • gulf of mexico
  • u.s. department of commerce
  • profilers/sounders
  • ngda
  • earth science
  • rain
  • nexrad
  • geographic region
  • ocean
  • hawaiian islands
  • doc/noaa/nesdis/ncei
  • radar
  • wind speed
  • convective clouds/systems (observed/analyzed)
  • cloud microphysics
  • convection
  • asia
  • kiribati
  • boundary layer winds
  • wind shear
  • south korea
  • wind profiles
  • radar reflectivity
  • vertical wind velocity/speed
  • central pacific ocean
  • solid precipitation
  • mid-latitude
  • upper level winds
  • cloud liquid water/ice
  • liquid precipitation
  • doc/noaa/nesdis/ncdc
  • hail
  • clouds
  • boundary layer
  • ngdaid39
  • atmospheric winds
  • doppler radar
  • environmental advisories
  • spectral/engineering
  • floods
  • puerto rico
  • bering sea
  • in situ land-based platforms
  • precipitation rate
  • next generation radar
  • mesoscale convective complex
  • rain storms
  • north atlantic ocean
  • pacific ocean
  • viewing geometry
  • climate and weather theme
  • earth remote sensing instruments
  • active remote sensing
  • national centers for environmental information
  • natural hazards

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