WMO, and NWP centres, want radiosonde stations to move towards sending high-resolution reports in BUFR. Extra levels, and detailed position information, improves NWP forecasts.
For more details see Ingleby et al (2016, BAMS, http://journals.ametsoc.org/doi/abs/10.1175/BAMS-D-15-00169.1) 'Progress towards high-resolution, real-time radiosonde reports'.
There are various templates available, summarised here for convenience along with notes on when they should be used (these notes have no official standing).
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