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NWS WSR-88D Level II Data Collection and Distribution Network Information

     View the Current Levell II Data Flow from     NWS Download ARCHIVED Level II Data from NCDC NEXRAD Data Inventory Visit the Level II Status pages at
Radar Feed Monitor From NWS                    Level II Data                    Level II Data
(Click image to visit site) (Click image to download) (Click image to visit site)

What are Level II data?
Level II data are the digital radial base data (Reflectivity, Mean Radial Velocity, and Spectrum Width) and Dual Polarization variables (Differential Reflectivity, Correlation Coefficient, and Differential Phase) output from the signal processor in the Radar Data Acquisition unit. The output also includes status information required to properly interpret the data (e.g., information on synchronization, calibration, date, time, antenna position, Nyquist velocity, and operational mode). Level II data are used for many purposes including: support of operations, maintenance and developmental activities at the ROC; activities directed toward algorithm and product improvement; research by universities; and private sector uses/applications. The Level II data are sent to the National Centers for Environmental Information by the NWS WSR-88D National Level II (NL2) system.

Level II data is continuously transmitted and archived from all DOC, DoD and DOT WSR-88D systems and are available via FTP download (

The interface control document describing the NEXRAD RPG Level II data format is available at:

The interface control document describing the TDWR SPG Level II data format is available at:

The interface control document describing the NPN data format is available at: NPN to Class 1 User ICD Bld 4.0.pdf

New Items

Eight WSR-88D sites (remaining DoD CONUS sites) now scheduled to be added to the NWS WSR-88D Level II Data Collection, Distribution, and Archive network 2013.

Click here to see Technical Implementation Notice 13-37.