WMOHDR

     WMOHDR allows specification of a WMO header for a GRIB message.

		WMO_ID / Origin_ID / DDHHMM

     The first six bytes of the header (WMO_ID) must be given.  The
     four-character originating center identifier (Origin_ID)
     defaults to KWBC.  The six-character reference day, hour, and
     minute (DDHHMM) defaults to values from the reference time
     in the GRIB1 PDS (bytes 15, 16, and 17, respectively), or 
     GRIB2 IDS (bytes 16, 17, nd 18).

     Bytes 7 and 12 of the WMO header are always blank.

     Only the 21-byte version of the WMO header is generated.