Guidance on WIS Discovery Metadata Records is provided in the metadata guidance, and an index to examples is available

The example for surface reports is on this page.

That page refers to a former version of the actual metadata for this GTS bulletin in BUFR format. The page explains the meaning of the elements of the record. You may download the linked file to use as the starting point for creating your own metadata record.

An example metadata record for a bulletin of surface synoptic records in FM12 SYNOP is also available. That record has the characters ??? in the fields that should be edited.