NOAA Next Generation Radar (NEXRAD) Level 2 Base Data

This dataset consists of Level II weather radar data 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. The NEXRAD products are divided into multiple data processing levels. The lower Level II data contain the three meteorological base data quantities at original resolution: reflectivity, mean radial velocity, and spectrum width. With the advent of dual polarization beginning in 2011, additional base products of differential reflectivity, correlation coefficient and differential phase are available. 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 3 products. NEXRAD data are acquired by the NOAA National Centers for Environmental Information (NCEI) for archiving and dissemination to users. Data coverage varies by station and ranges from June 1991 to 1 day from present. Most stations began observing in the mid-1990s, and most period of records are continuous.

Tags: active remote sensing, asia, atlantic ocean, azores, bering sea, boundary layer, caribbean sea, central pacific ocean, continent, doc/noaa/nesdis/ncdc, doc/noaa/nesdis/ncei, doc/noaa/nws/roc, doppler radar, doppler velocity, earth remote sensing instruments, earth science, east china sea, eastern asia, geographic region, guam, gulf of alaska, gulf of mexico, hawaiian islands, in situ land-based platforms, kiribati, land surface, mid-latitude, national centers for environmental information, national climatic data center, national weather service, nesdis, nexrad, next generation radar, noaa, noaa onestop project, north america, north atlantic ocean, north pacific ocean, northern hemisphere, ocean, okinawa, pacific ocean, profilers/sounders, puerto rico, radar, radar operations center, radar reflectivity, radar sounders, sar, sensor characteristics, south korea, spectral/engineering, spectrum width, troposphere, u.s. department of commerce, united states of america, vertical location, viewing geometry, weather stations, weather stations/networks, western pacific ocean, yellow sea
Organization: National Oceanic and Atmospheric Administration, Department of Commerce