Have not seen any surge numbers above 30 ft for Katrina. 30 ft measured in Biloxi, and 29 and 30 ft measurements in BSL, these are official numbers. Am going to be getting some more info on this soon. Remember there were waves on top of the surge, but only right at the shoreline. The surge right at the coast went inland an average of 1/2 mile and for the most part between 1/4 mile and 3/4 mile, as can be seen by comparison of NOAA high-resolution images showing the debris line at the edge of the surge, with topographic maps that show elevation. Exceptions: All of Plaquemines Parish was at a low enough elevation as to probably be completely underwater from Venice to some points northward as Katrina passed over. Also the topography of St Bernard rendered it very vulnerable to flooding from the Gulf side, even without the levee and canal failures. Some areas inland of BSL continued at a low enough elevation to allow the surge further inland. The surge also affected shoreline bordering bays, inlets, rivers, and streams. The key to determining if surge will hit a location would be the elevation and proximity the coastline, which would be hit with waves as well.

It will be interesting in future to see classification and categorization of hurricanes beyond the intensity scale. I will be interested someday to see analysis of more subtle characteristics that will point to specific behaviors.

For instance, with Katrina, the pressure drops came first and then winds caught up. This catch up took a long time to complete; the first several days over the GOM pressures were always lower than the corresponding windspeeds while fighting dry air.

With Rita, the windspeeds increased ahead of the pressure and organization of the storm. The time this discrepancy was most obvious was when the winds increased to Cat 2 level.

Looking at it from a casual point of view you might say each storm has its own personality. However I am sure it is a set of commonalities that will eventually be defined and will be able to lead to identification of storm characteristics that will help forecast intensity and other behaviors.