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.

Data and Resources

Additional Info

Field Value
Last Updated May 8, 2019, 05:44
Created June 7, 2017, 23:12
access_constraints ["Cite as: NOAA National Weather Service (NWS) Radar Operations Center (1991): NOAA Next Generation Radar (NEXRAD) Level 2 Base Data. [indicate subset used]. NOAA National Centers for Environmental Information. doi:10.7289/V5W9574V [access date].", "Distribution liability: NOAA and NCEI make no warranty, expressed or implied, regarding these data, nor does the fact of distribution constitute such a warranty. NOAA and NCEI cannot assume liability for any damages caused by any errors or omissions in these data. If appropriate, NCEI can only certify that the data it distributes are an authentic copy of the records that were accepted for inclusion in the NCEI archives.", "Use liability: NOAA and NCEI cannot provide any warranty as to the accuracy, reliability, or completeness of furnished data. Users assume responsibility to determine the usability of these data. The user is responsible for the results of any application of this data for other than its intended purpose."]
bbox-east-long -64.0
bbox-north-lat 68.0
bbox-south-lat 11.0
bbox-west-long 124.0
coupled-resource []
dataset-reference-date [{"type": "publication", "value": "1991"}]
frequency-of-update continual
graphic-preview-description WSR-88D RADAR
graphic-preview-type GIF
guid gov.noaa.ncdc:C00345
licence []
metadata-date 2019-04-24
progress onGoing
resource-type dataset
responsible-party [{"name": "DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce", "roles": ["pointOfContact"]}]
spatial {"type": "Polygon", "coordinates": [[[124.0, 11.0], [-64.0, 11.0], [-64.0, 68.0], [124.0, 68.0], [124.0, 11.0]]]}
spatial_harvester true
temporal-extent-begin 1991-06-05