Johanna,
via HYCOM.org currently offer the following,
"HYCOM + NCODA Gulf of Mexico 1/25° Reanalysis (GOMu0.04/expt_50.1)"
Resolution: 1/25° (0.04)
Institution: Naval Research Laboratory
Date/Data Range: 1993-01-01 to 2012-12-31
https://www.hycom.org/data/gomu0pt04/expt-50pt1
This dataset is accessible via all of your access methods: THREDDS,
FTP, HTTP/HTTPS, and rsync.
There is currently no higher spatial/temporal resolution available in
the GoM for public release at this time.