![]() Search the data archive to submit an order via the interface or download files if available.ĭynamic GIS mapping application to locate stations and data for selected layers. Most stations began observing in the mid-1990s, and most period of records are continuous. Data coverage varies by station and ranges from May 1992 to 1 day from present. NEXRAD data are provided to the NOAA National Centers for Environmental Information (NCEI) for archiving and dissemination to users. Radar messages for Level 3 are sent by the radar site to users in order to know more about the radar status and special product data. These include storm structure, hail index, mesocyclone identification, tornadic vortex signature, and storm tracking information. Overlay products for Level 3 are alphanumeric data that give detailed information on certain parameters for an identified storm cell. Estimates are based on reflectivity to rainfall rate (Z-R) relationships. Precipitation products for Level 3 include estimated ground accumulated rainfall amounts for one and three hour periods, storm totals, and digital arrays. General products for Level 3 include the base and composite reflectivity, storm relative velocity, vertical integrated liquid, echo tops and VAD wind profile. There are over 40 Level 3 products available from the NCDC. sites, though non-US sites do not have Level 3 products. Level 3 products are recorded at most U.S. The Level 3 data consists of reduced resolution, low-bandwidth, base products as well as many derived, post-processed products. From the Level 2 quantities, computer processing generates numerous meteorological analysis Level 3 products. Level 2 data are recorded at all NWS and most USAF and FAA WSR-88D sites. The lower Level 2 data are base products at original resolution. The NEXRAD products are divided in two data processing levels. 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. Dual Pol radar capability adds vertical polarization to the previous horizontal radar waves, in order to more accurately discern the return signal. 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. Super resolution makes a compromise of slightly decreased noise reduction for a large gain in resolution. ![]() 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. ![]() ![]() 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. During 2008, the WSR-88D radars were upgraded to produce increased spatial resolution data, called Super Resolution. The radar scan times 4.5, 5, 6 or 10 minutes depending on the selected VCP. 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 two modes employ nine Volume Coverage Patterns (VCPs) to adequately sample the atmosphere based on weather conditions. 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. This is a 10 cm wavelength (S-Band) radar that operates at a frequency between 2,700 and 3,000 MHz. NEXRAD stations use the Weather Surveillance Radar - 1988, Doppler (WSR-88D) system. 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 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. This dataset consists of Level 3 weather radar products collected from Next-Generation Radar (NEXRAD) stations located in the contiguous United States, Alaska, Hawaii, U.S.
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