Below are plots of SYNOP/BUOY/radiosonde BUFR coverage for May 2021 - reports as decoded at ECMWF, some reports not in standard BUFR are not decoded. Daily coverage of BUFR reports (updated automatically) is available from the Monitoring Maps. See also timeseries and maps from the NWP system: Monitoring of Conventional observations
Please can data producers ensure that there is a reasonable overlap of TAC and BUFR data on the GTS (at least two months, EUMETNET and GCOS recommend six months), any attempt to rush the change will result in more errors, extra work for NWP centres and possibly worse forecasts. Most countries give notice via METNOs or the WMO Operational Newsletter. Note also that reformatted TEMP reports still as separate parts are not regulation BUFR and cause problems for NWP centres (some more than others).
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