NEXRAD Data Stream

LEVEL I DATA:
The archive Level I interface is located in the Radar DataAcquisition (RDA). Level I data are the analog, time-domain output of the receiver. Information regarding synchronization, calibration, date, time, antenna position, and status is also available. Level I data are not permanently archived.


LEVEL II DATA:
The archive Level II interface is also located at the RDA. The Level II data are digital base data output from the signal processor and include base reflectivity, mean radial velocity and spectrum width. The output also includes information on synchronization, calibration, date, time, antenna position, and operational mode. Level II data are recorded on 8 mm magnetic tape and sent to NCDC for permanent storage. Software exists that will decode the raw Level II data into custom imagery.


LEVEL III DATA:
The archive Level III interface is located at the Radar Products Generator (RPG). A set of pre-determined products defined in Federal Meteorological Handbook (FMH)-11 part A, comprise the Level III data which is archived on WORM Optical Disk and sent to NCDC for permanent storage. The products


LEVEL IV DATA:
The archive Level IV interface is located at the Principle User Processor (PUP). Any data or information available at the PUP may also be recorded on SCSI tape or WORM Optical disk at the discretion of the PUP operator. These Level IV data are generally for local use and are not permanently archived at NCDC.