DCUAIR

    DCUAIR decodes upper air sounding data from a real-time data
    feed, or from a file fed to the program through standard input, and
    writes the data to a GEMPAK sounding file.  The program is controlled
    by inputs to the command line.

    The inputs are program options and the output file name or template.
    For example, for real-time data feeds:
    
	dcuair [options] output_file

    If running the program interactively with standard input, the -c
    option must be used.  The input file must be also be specified.
    For example:

	dcuair -c YYMMDD/HHNN [other_options] output_file < input_file
    
    A template may be used to specify the output file name.  The file
    name template uses the date and time of the bulletin or report
    to replace the following characters.

	YY or YYYY	Year
	MM		Month number
	DD		Day
	HH		Hour
	NN		Minute

    The dcuair decoder may be used to decode dropsonde data.  If this
    is done, it is advisable to run a separate instance of the decoder
    from that used to decode standard upper air data.  In this case, 
        a) the maximum number of stations to add should be set to 
           at least 50 on the command line ( -a 50 ), since all
           dropsonde reports are treated as additional stations 
        b) the maximum number of times should be set to 24 on the
           command line ( -m 24 ), to create hourly entries instead of
           3-hourly entries
        c) only upper air bulletins having WMO bulletin headers
           beginning with UZ should be sent to the decoder
	d) the cutoff height in meters for using a "close-to-the surface"
	   wind in place of a missing surface wind may be specified using 
	   the -w option.  The default value is 20 meters