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All the four WIGOS Monitoring Centres - ECMWF, DWD, JMA and NCEP- are providing quality monitoring reports for upper-air observations.  Like the surface reports, these include qualitative as well as quantitative information. The quantitative information provided is obtained by aggregating the O-B departures into two main categories: layer between the first pressure level up to 100 hPa inclusive (Trop); and the layer from 100 hPa up to the last reported level (Stra). The quantitative information for the aforementioned layers consists of both the mean and standard deviation of O-B departures over the layer for the following observed physical quantities: upper-air temperature, upper-air humidity and upper-air wind. Provision of these data reports (four daily, centred at the main synoptic hours, 00, 06, 12 and 18UTC), typically happens 24 hours after the actual observation. The availability, quality and completeness of these conventional profiling observations can be easily assessed based on the information provided by the monitoring reports. It is worth mentioning that for the high-resolution BUFR reports, two messages are disseminated on the Global Telecommunication System (GTS): a preliminary message containing the measurements from the surface up to 100h Pa (TTAA=IUK header - I, Observational data Binary coded, U, upper-air message and K, radiosonde from fixed land station up to 100 hPa) and the final message containing the entire sounding from surface to balloon burst (TTAA=IUS, header - I, Observational data Binary coded, U, upper-air message and S, radiosonde from fixed land station up to balloon burst). ECMWF, JMA and DWD use the full BUFR message (i.e., IUS bulletin), and only if the full one is not available they use the IUK bulletin. Therefore, all NWP monitoring reports reflect this, i.e., the ascent report that contains the highest level will be used to calculate the statistics (i.e., IUS bulletin). This is a case of duplicates, however, if a radiosonde is launched 30 mins after the one that went wrong (i.e., burst at quite low altitudes), both will be used because they are not considered duplicates in those circumstances.

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