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The impact of the high space-temporal variability of the wind field during the moderate and intense storm stages of a tropical cyclone on the wave field as computed by the numerical model WaveWatch III is investigated in this work. The realistic wind fields are generated by a high-resolution implementation of the HWRF model in the Gulf of Mexico and stored over 15 min intervals. The spatial structure of the wind field computed by HWRF is highly variable in space and time, although its mean structure is very similar to that described for parametric hurricanes already specified in the previous studies. The resulting storm-generated wave fields have a persistent structure, with wave maxima present in the forward quadrants of the storm and in the rear quadrant II. This structure is determined by the strong winds and the extended fetch condition in quadrants I and II, as well as by the translation speed of the storm. When a shorter time interval is analyzed (e.g., a 3 h period, when the storm becomes a category 1 hurricane), the structure of the mean wind field may differ greatly from the mean field calculated with a sufficiently longer period; however, the spatial distribution of the wave field around the hurricane tends to maintain its typical spatial structure. The use of wind fields with reduced time variability (e.g., with a 3 h moving average) does not change the structure of the mean wave field, but reduces the mean wave height values by up to 10%.

Extreme weather events such as hurricanes are expected to become more severe with the human-induced increase in average global temperatures, exacerbating the risk of major damage. Efforts to predict these events typically require detailed hydrodynamic data that are difficult to collect in the field. Here, nearshore data collected with three ADCP moorings were used to describe the hydrodynamics induced by Hurricane Harvey along the southern Texas coast. Wave spectra and nearshore current variations were analyzed along the hurricane’s trajectory and compared to other offshore locations. The results indicate that winds intensified along the coast as Harvey approached the Port Aransas coastline. Southerly wind stresses of ~−0.9 Nm−2 generated ~2 ms−1 depth-averaged flows towards the southwest close to landfall in the north, while flows of ~1 ms−1 and −1 were measured in the center and the south of the study site, respectively. The hydrodynamics induced by the hurricane were compared to those induced by an intense synoptic-scale cold front (CF). Both events generated southward-directed alongshore wind stresses of similar magnitudes (τy ~−0.4 Nm−2) that caused similar depth-averaged flows (0.5 to 0.7 ms−1) and wave energy conditions (Hs of ~4 m) in the south. Harvey caused extremely energetic conditions close to landfall in the north compared to the CF; depth-averaged flows and Hs of 2 ms−1 and 10 m were induced by Harvey, as opposed to 0.6 ms−1 and 4 m by the CF, respectively. While intense currents (>1 ms−1) and waves (Hs > 4 m) lasted for less than a day during Harvey, these persisted a few days longer during the CF. This study highlights the relevant role of synoptic-scale cold fronts in modulating the nearshore hydrodynamics, which occur more frequently than tropical cyclones in the northwestern Gulf of Mexico.