[TomGuy]

IIRC, just before it hit landfall, Katrina dropped from a Cat 5 to a Cat 3. That seems to be typical when hurricanes first hit the shoreline.

It still did massive damage, however.

[rodguy911]

In the meteorological discussion chat room they say that is not as likely with Gustave due to atmospheric conditions north of the storm.

[Sunnyflorida]

“It still did massive damage, however.”

It whoa-ed up. Flood damage. Mobile homes and poorly constructed homes get wind damage but the slow winds built up the surge - but not in NO. That was a pure engineering failure. The water never topped the dykes. The dykes failed.