Mississippi SLOSH models

[weatherwindow]

What's the record for the largest (windfield) hurricane in the Atlantic basin? Because while Katrina was very large, Category Fives tend to come in two types: tightly wound tornado-like bombers like Andrew, Camille, and Labor Day...and then the monsters like Katrina, Rita, Mitch, Allen, Gilbert...etc. It's really not that unusual at all for a Category Five storm to be over 300 or 400 miles across...you don't just take your average Cat3 like Jeanne and stick some 175mph winds into the center.

I actually think that the SLOSH models are probably outdated, because we just don't know that much about Category 5 hurricanes and what they can do, because they're so rare. (or used to be so rare, anyway)

....although there may be other contenders, the largest i am aware of was the south fla hurricane of sept 1947...winds to 100mph experienced over 100mi of coastline(fowey rocks light(south of miami) to jupiter inlet), hurricane force winds experienced over 240mi(tavernier to cocoa beach) and gale force/trop storm force winds over 300mi(big pine key to daytona beach).....one truly immense storm....still holds the record for the highest sustained winds measured in florida..155mph at the hillsboro inlet light.....remember this was measured and sustained and officially recognized..................any other candidates?.........rich

[Ixolib]

...This summer may show that we need to spend more on research and modeling to produce new, more accurate flood maps too.

Which, I suppose, is my main point. The flood maps of the recent and long-term past were/are based on incomplete data because the technology utilized in their development is obsolete compared to the technology available today. Furthermore, the data that was incorporated into their structure was certainly based on recorded history which has just been proven to be obsolete as well.

I agree that the cities would most probably not get involved in lot-by-lot elevation measurements, but surely the technology exists - via satellite and other economical means - to get a much better measure and display it in a much more detailed manner.

And finally, I don't believe the present maps are based so much on "storm surge" as they are based on potential for flooding caused by rainfall, and on up-stream conditions affecting down-stream areas in local rivers. As for the Bay, it ebbs and flows in exact accordance with the tidal flow in the GOM. Consequently, I can't imagine that the Bay - except perhaps right on the shoreline - was incorporated to any great degree in the flood mapping either.

You are absolutely right, the flood mapping - and resultant models - must be reconsidered with a new mindset and a fresh outlook to its overall mission. And the potential for storm surge must be highly considered in their development. Times have changed!

[Derek Ortt]

I do not have a recon fix from the shelf for Camielle, and I do not believe one is made even

[tailgater]

the max open ocean surge is about 3 feet. The water excapes from below, meaning the open ocean surge is almost entirely due to the low pressure. The wave height is a function of how strong the storm was over the open ocean, if the storm moves at the same speed as the waves. But the overall storm surge is not that dependent upon its intensity in the open ocean

Sorry to bring this back up but I'd like to challenge this reasoning. True that over open water there may be only a 3ft surge but with strong winds over basically the same direction over a long period of time can pile up very large tides well before (days) the SURGE effects the area. Tides could be as high 5ft above normal along the east side of La. coast from 20kt ese winds over that area.
I guess what I'm trying to say is that storm surge forecast (Slosh models) have a lot of variables to consider before they can be used with much confidence.

[Derek Ortt]

thats due to the longwave action, which is totally seperate from the surge