The Mexican current as represented by the Mariano Global Surface Velocity Analysis (MGSVA). Click here for example plots of seasonal averages.
In addition to the Loop Current, there is suggestion of a western boundary current in the western Gulf of Mexico which Sturges and Blaha (1976) called the Mexican Current. The Mexican current is found in the western part of the gulf stream between a cyclone/anticyclone pair (Maul and Herman, 1985). This cyclone/anticyclone pair has been seen in numerous studies (Nolin and McLellan, 1967; Merrell and Morrison, 1981; Brooks and Legeckis, 1982). Brooks and Legeckis (1982) found a jet-like eastward flow under the frontal boundary between the cyclone and anticyclone. Maximum speeds for this current are 74 cm/s with transports of 31.5 Sv while between the cyclone and anticyclone. They estimated a net transport across the section of 8.9 Sv. This corresponds well with Sturges and Blaha's (1976) estimation of speeds of 70-100 cm/s and transport of 10 Sv. Numerical models of Hurlburt and Thompson (1982) and Elliot (1982) suggest that the cyclone/ anticyclone pair is formed as a result of forcing from anticyclonic rings generated by the Loop Current. Wind stress does appear to strengthen this feature (Merrell and Morrison, 1981) but it does not appear to be the sole source of the anticyclone/cyclone as Sturges and Blaha (1976) had suggested.

References

Brooks, D.A., and R.V. Legeckis, 1982: A ship and satellite view of hydrographyic features in the western Gulf of Mexico, Journal of Geophysical Research, 87, 4195-4206.

Elliot, B.A., 1982: Anticyclonic rings in the Gulf of Mexico, Journal of Physical Oceanography, 12, 1292-1309.

Hurlburt, H.E., and J.D. Thompson, 1982: The dynamics of the Loop Current and shed eddies in a numerical model of the Gulf of Mexico. In Hydrodynamics of semi-enclosed Seas, Amsterdam, New York: Elsevier. J.C.J. Nihoul(ed.), 243-298.

Maul, G.A., and A. Herman, 1985: Mean Dynamic Topography of the Gulf of Mexico with Application to Aatellite Altimetry, Marine Geodesy, 9, 27-44.

Merrell, W.J., Jr., and J.M. Morrison, 1981: On the circulation of the western Gulf of Mexico with observations from April 1978, Journal of Geophysical Research, 86, 4181-4185.

Nowlin, W.D. Jr., and H.J. McLellan, 1967: A Characterization of the Gulf of Mexico Waters in Winter, Journal of Marine Research, 25, 29-59.

Sturges, W., and J.P. Blaha, 1976: A western boundary current in the Gulf of Mexico, Science, 192, 367-369.