Motivated by the lack of detail in the initial report regarding surge, I finished looking at the FEMA Katrina flood maps for MS, and it appears their overall assessment is pretty good. The max amount of surge was probably around 24-25 feet, and that was only along a couple of small areas of immediate coastline (although I suspect Lakeshore and Clermont Harbor had similar surge as well). In terms of category, all but that tiny percent or two of the area flooded was category 3 or less. The area of the MS coast that received Cat 3 surge was extraordinary; it went all way to just east of the Pascagoula city limits, only a couple miles from the AL border. The flooding of the Pascagoula River basin was also extraordinary.

Is there a chance we can move all these posts on the Katrina report to a new thread addressing the report?

If so, I'll post more detail on the surge analysis (which mainly involved going back and forth between the MS HES maps, which contain the SLOSH model results, but in terms of category, not elevations, which are site-dependent due to topography, and the FEMA flood and elevation maps).

I haven't had a chance to look at any flooding in LA but am interested in hearing what others have found. I suspect St Bernard got a wicked surge, with more velocity than any of the other areas, and that the majority of Slidell's surge didn't come from Lake P, but came right over the lowlands from MS, and from Lake Borgne.