How can a hurricane reverse the flow of massive rivers?

Question

Using Ida reversing the Mississippi as an example, sounds pretty insane to me.

In: Earth Science

Answer 1

Hurricanes bring a “storm surge” with them when they make landfall. The power of the sustained winds at the leading edge of the storm literally pushes seawater up onto the coastline, sometimes many feet deep.

The swampy outlet of a river may only have a few feet of grade over many miles, so a twenty foot storm surge will make the ocean higher than the river and it will flow backwards up the river for a good distance.