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The ocean circulation in the western Gulf of Mexico is influenced by Loop Current eddies (LCEs), which affect the thermohaline structure and distribution of environmental variables as well as the design and management of offshore structures and maritime activities. In this study, we assess the ocean circulation and its variability by applying dual self‐organizing maps (SOMs) to a 20‐year data set (1993–2012) of salinity and currents at a depth of 200 m from a Hybrid Coordinate Ocean Model. The geospatial variability is characterized via a 7 × 7 SOM, which is further grouped into seven patterns, while the temporal variability is characterized as six distinct regions using a 2 × 3 SOM. The influence of LCEs on the upper slope occurs along the 200‐m isobath, a zone under constant pressure by strong currents from impacting eddies. The temporal pattern variability also reveals a clear zone of LCE impact on the continental slope (between latitudes 22°N and 25°N) and a dominant offshore transport pattern around latitudes 25°N to 26°N. A rectified wavelet power spectral analysis reveals a frequency of LCE impact oscillating around four to five months with an estimated ring lifespan of 1 year.

This paper describes the application of a thirdgeneration wave model and a hydrodynamic model to determine extreme waves and water levels associated to the incidence of tropical cyclones along the Mexican coast. In addition to historical records and to overcome the limitation associated to data scarcity in Mexico, we employ information from 3100 synthetic events generated from a statistical/deterministic hurricane model. This enables the generation of a more robust database for the characterization of extreme water levels along the Mexican coast. The procedure incorporates a storm track modeling approach where, for each hurricane (historic and synthetic), the entire track is numerically reproduced as it crosses the ocean and makes landfall. Extreme values for both, waves and storm surge, are determined through an extreme value analysis at each mesh element, allowing for the identification of their spatial variability. Results for the Gulf of Mexico show that highest waves are expected along both the Caribbean Sea and the northern coast of the Gulf of Mexico, while extreme water levels due to storm surge are identified in the northern part of the Yucatan Peninsula. On the other hand, along the Pacific coast, extreme values for waves are identified at the central mainland Mexico while storm surge is minimal. The methodology is proved to be a good alternative in the reproduction of continuously varying tropical cyclone climatology along the Mexican coastline, and it provides a rational approach for assessing the hurricane-induced risk in coastal areas.

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