Storm surges are often related to coastal dune erosion. We found that, for specific coastal settings, storm surges may enhance dune growth rather than only undermine it. Using a computer model and elevation data, we noticed that storm surges could deposit sand onto the sand flat from sand previously deposited closer to the sea. As they move to areas farther from the sea, it becomes easier for the wind to move this sand to the dunes. These findings may help coastal managers and policymakers.