Below are plots of radiosonde/SYNOP BUFR coverage for 5-9 October 2014 - reports as decoded at ECMWF, some reports not in standard BUFR are not decoded.
Please can data producers ensure that there is a reasonable overlap of TAC and BUFR data on the GTS (EUMETNET recommendation is six months), any attempt to rush the change will result in more errors, extra work for NWP centres and possibly worse forecasts. Note also that reformatted TEMP reports still as separate parts are not good BUFR and cause problems for NWP centres (some more than others).
Radiosonde coverage
About 60% of stations report in BUFR, but most (apart from the dark blue stations in the plot) report reformatted TEMP (see "structure" page). Reports may be incomplete (eg data above 100 hPa missing).
The main changes since early August are for North America - all US stations are now producing BUFR that can be decoded by ECMWF (still as separate parts unfortunately). BUFR report from some Canadian stations are available at ECMWF - but not generally on the GTS yet. As the Canadian stations started producing BUFR their TAC (TEMP) reports changed GTS bulletin header - and there was a GTS routing problem that meant that NWP centres in Europe did not receive the TEMP reports (now rectified)
(Grey: TAC reports but no BUFR, Purple: BUFR reports but no TAC, Red *: position error. Light/dark blue indicates low/high vertical resolution BUFR data).
Surface coverage
Almost 70% of stations now report in BUFR, with some filling in over South America and Africa since early August. There was a temporary problem at ECMWF that meant that French reports, and others using the same template, were not processed for a while. Many of the position errors have been corrected in the last two months.
Three countries (UK, Eire and Netherlands) have announced that their TAC SYNOP transmissions will be terminated on 3rd or 4th November 2014 (see SYNOP ).
(Grey: TAC reports but no BUFR, Purple: BUFR reports but no TAC, Red *: position error. Light/dark blue indicates that there are less/more than 60% of the reports available in BUFR.)
