**5. Conclusions**

Cold fronts and hurricanes have different wind patterns, and temporal and spatial characteristics: cold fronts usually have abrupt changes in wind direction (from southern quadrants to northern quadrants) before and after the frontal passage, with several hours to 3 days in duration, and 2000–3000 km length of front and a narrow width (less than 10 km) of the front. However, a hurricane has a radius of maximum wind (30–50 km) larger than the width of the frontal zone, and with a longer impact period of about a few days to a week, stronger maximum wind, and a rotating wind. Due to these differences, a cold front is more likely to result in a trough in water level post front, while hurricane tends to produce a more significant storm surge even severe inundation. The maximum of the variation in water level caused by Hurricane Barry was about 3 times of that caused by a cold front. The ratio is variable at different locations relative to the location of landfall.

Surface and bottom flows inside the Barataria bay have unidirectional movement except that surface flow has a larger magnitude. Currents tend to flow in the direction of wind in the shallower water region, but against the direction of wind in the deeper water region, resulting in a returning flow in the middle of bay. Water is transported out of the bay after a cold front passage. However, it is transported into the bay after Hurricane Barry's landfall. Volume flux through four inlets of Barataria Pass follows two EOF modes found by Li et al. [50] under a cold front event, in which water tends to be transported out of (into) the bay through Barataria Pass and Pass Abel during southerly (northerly) wind and into (out of) the bay through Caminada Pass and Quatre Bayou under southerly (northerly) wind. However, the volume flux through the four inlets of Barataria Bay shows different pattern under Hurricane Barry: water is flowing into (out of) the bay through Barataria Pass, Pass Abel, and Quatre Bayou under northerly (southerly) wind. The flux is the opposite through Caminada Pass, which is flowing out of (into) the bay during southerly (northerly) wind. The maximum water volume flux induced by hurricane is about 4 times that induced by a cold front event, indicating that the influence of four cold fronts is comparable with one hurricane event.

**Author Contributions:** Methodology, C.L.; validation, W.H.; formal analysis, W.H.; writing—original draft preparation, W.H.; writing—review and editing, C.L.; project administration, C.L. All authors have read and agreed to the published version of the manuscript.

**Funding:** The study was supported by National Science Foundation and Natural Environment Research Council (NSF-NERC 1736713), Bureau of Ocean Energy Management (M15AC000015), and GCOOS through NOAA-NOS-IOOS-2016-2004378.

**Acknowledgments:** The numerical modeling was performed on the cluster computers of the Louisiana Optical Network Initiative (LONI) HPC systems at LSU.

**Conflicts of Interest:** The authors declare no conflict of interest.
