DSS presents a global synoptic set of 12 hourly upper air data reports. These were operationally collected by NMC. They include radiosondes, pibals and aircraft reports received via the Global Telecommunications System (GTS). NMC used Automated Data Processing (ADP) to decode and reformat the GTS reports. This data was the primary input (known as "B-3s") for NMC's modeling and forecasting. It was also a major input for the NCEP/NCAR and ECMWF Reanalysis Projects. The NCAR document TN404 An Introduction to Atmospheric and Oceanographic Datasets, (chapter 3) discusses the collection of this data in greater detail.

The ADPUPA data includes land and ship launched radiosondes and pibals. Data may be available at up to 20 mandatory levels from 1000mb to 10mb, plus a few significant levels. The AIRCFT data includes flight level reports from commercial, military and reconnaissance sources. The data may include pressure, d-value (deviation from standard atmosphere geopotential height), temperature, dewpoint, wind direction and speed.

This dataset is in an NCAR blocked version of the NMC Office Note 20 (ON20) format, which involves using the DSS RPTOUT software. For data after 1972 see DS353.4. More information is available.