Regions of Mississippi

Jackson sits on the Pearl River at the edge of the Mississippi loess bluffs, which is why it floods the way it does: the Ross Barnett Reservoir is upstream of the city, the river runs through the middle of it, and the 1979 Easter Flood and the February 2020 crest both put the same neighbourhoods under. It is also as far inside Dixie Alley as a metro gets — the supercells come out of Louisiana in the evening and are over Hinds and Rankin after dark.

The Coast is 62 miles of beach with the Mississippi Sound and four barrier islands in front of it, and the islands are the whole story. They take the first of the surge and they are shrinking, which is why the same storm does more now than it would have in 1969 — and 1969 was Camille. Day to day the Sound runs the forecast instead: it holds the sea breeze offshore until early afternoon, then fires it inland, so Wiggins and Poplarville get the thunderstorm that Gulfport watched build over the water.