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Almost all reformatted TEMP reports are sent as separate parts (A/B/C/D), this is contrary to the BUFR coding rules (there should be a single report containing data for the whole ascent) and reformatted TEMP reports are regarded as unusable by ECMWF and most other NWP centres. BUFR reports generated directly from the radiosonde raw data are much better.
See note on Radiosonde BUFR templates
BUFR radiosonde data are archived at NCEI
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