NDBC THREDDS Server Catalog https://dods.ndbc.noaa.gov/thredds/catalog/data/wlevel/spgf1/catalog.html

Dataset Size Last Modified
     Folder  spgf1   --
         spgf1.ncml 302.0 bytes 2017-11-15T16:15:20.291Z
         spgf1l1996.nc 667.4 Kbytes 1996-12-15T23:00:00Z
         spgf1l1997.nc 567.6 Kbytes 1997-12-31T23:00:00Z
         spgf1l1998.nc 14.69 Kbytes 1998-01-07T23:00:00Z

National Data Buoy Center THREDDS Server at National Data Buoy Center see Info
THREDDS Data Server [Version 4.6.14 - 2019-07-23T11:04:31-0600] Documentation