Global Upper Air Rawinsonde, DSI-5683 is a historical data set archived at the National Climatic Data Center (NCDC). This data set was produced from upper air data received during the 1970s from the National Meteorological Center (NMC) of the U.S. NOAA National Weather Service. NMC is now the National Centers for Environmental Prediction (NCEP). The data in this file are sorted by stations (WMO) ... number. The first level is always the surface, standard and significant levels then follow in decreasing pressure (ascending height) order. The major parameters that make up this file are observation time (year, month, day, hour), number of levels, pressure of level (mb to tenths), height of level (geopotential meters), temperature of level (degree Celsius to tenths), relative humidity of level (%), and wind direction (whole degrees) and wind speed (meters per second) of the level. This data were assimilated from normal international communication channels and no detailed quality control measures were employed when converting to DSI-5683. The observations, therefore, were subject to the usual errors inherent in such a collection. This file has been replaced by DSI-6202 and all requests for data should use this new file.