What can 10 feet of storm surge do to Miami Beach?

[zlaxier]

Apparently because of the deep water offshore, this is the maximum amount of storm surge possible.

Would the entire island be covered with 10 feet of water with the high waves driving the surge inland to merge the atlantic ocean and biscayne bay? Is 10 feet of storm surge enough to destroy homes and foundations or just gut the first floor of a structure?

Also what about the west side of Miami Beach and the islands in Biscayne Bay? Would they get higher surges than the ocean side since Biscayne Bay is shallow?

[Audrey2Katrina]

Apparently because of the deep water offshore, this is the maximum amount of storm surge possible.

Would the entire island be covered with 10 feet of water with the high waves driving the surge inland to merge the atlantic ocean and biscayne bay? Is 10 feet of storm surge enough to destroy homes and foundations or just gut the first floor of a structure?

Also what about the west side of Miami Beach and the islands in Biscayne Bay? Would they get higher surges than the ocean side since Biscayne Bay is shallow?

If you're really interested in how hurricanes can/might affect Miami, try this link:

https://www.cnmoc.navy.mil/nmosw/tr8203nc/miami/text/sect4.htm

Lots of data/info there.

A2K

[CHRISTY]

it probably would really damages our beaches...

[Derek Ortt]

Biscayne Bay can have 15 to 20 feet as evidenced by Andrew. However, there is a ridgeline of about that height very near the coast; thus, the surge wont go very far inland. However, due to the high rises, Miami is very vulnerable to the wind

[Patrick99]

I don't believe Miami Beach has been tested to that magnitude storm surge since 1926, and I'm sure it looked a lot different then. I have to believe that a 9-10 foot surge would simply wash over Miami Beach, briefly merging ocean and bay.

If this happened now, I'd have to think that South Beach wouldn't be South Beach for an awful long time. A lot of tough New Orleans-style questions regarding the wisdom of rebuilding there would have to be answered.

Of course, it *will* happen again someday. We've been heedless of our own past with all this rampant overdevelopment. Miami Beach SHOULD be nothing but a mangrove-studded barrier island/state park.

[Derek Ortt]

would 9 top 10 feet be enough to destroy the structures? I would say that from the surge, no as the structures at Marathon rfemained in tact from a similar surge during Wilma. That said, the lower floors would be gutted and oceanfront property would likely be smashed by the waves, as occurred in Jeanne from a 6 foot surge.

The wind though may still devastate Miami Beach. Cat 4 winds and high rises do not mix very well

[zlaxier]

The damage would end up being cumulative, especially in Cat 4 and 5 winds.

The storm surge will break windows and doors and gut the first floor and possibly weaken the foundation, allowing the strong winds to get inside the building and destroy it.

In the end, the structure will be destroyed by both surge and wind.

[gatorcane]

How about the 1926 Great Miami Hurricane? What was the storm surge like? I would imagine it would be similar. Does anybody have that data?

[MiamiensisWx]

The September 1947 hurricane produced an unusually large surge and wave action along all of the metropolitan southeast Florida coast, likely due to it's immense size.

[Jim Cantore]

The September 1947 hurricane produced an unusually large surge and wave action along all of the metropolitan southeast Florida coast, likely due to it's immense size.

155mph winds helps too

[bvigal]

If Wilma generated 10foot in Marathon, and Jeanne, which hit way up north of Jupiter, generated 6foot, I find it hard to believe 10ft is the maximum possible in MiamiB?? Is that for real? With a direct hit from a Katina-type storm.... if the hurricane eye raised water 10 feet with 145kt winds on top of that, it seems the shore slope would not protect from 20ft surge right in the eye. Just guessing here, please tell me if this is fantasy...

If a 20-ft surge in a storm that strong hit Miami Beach, I think it would look a lot like Biloxi. The high rises might remain with only lower 2 floors gutted, but a lot of windows out, with damaged plant (air cond, wiring, etc.) rendering them essentially unusable until after considerable repairs. Anything 1 or 2 stories would be stripped rather bare, or gone altogether.

[Derek Ortt]

Florida Bay is about 3 feet deep; thus, the cause of the surge

Jeanne was a very large category 3 hurricane, yet it only produced 6 feet. Had it have hit MS, the surge likely would have been about 25 feet

[bvigal]

Thanks for that clarification, Derek. I misunderstoond and thought you meant Jeanne's 6ft surge was in Miami area, duh, what was I thinking, LOL!

So MiamiB just can't get more than 10ft, then? That's good news!!

Can you answer another question for me? Jeanne never obtained 4 or 5 status, as did Katrina. After last year, has it now been concluded, scientifically, that surge can also be dependent upon the peak of the storm before it makes landfall, i.e. if cat 5 then down to cat 3 at landfall, vs storm that peaks at cat 3 then makes landfall? If so, what is the highest surge possible in Jupiter area? (I have family there.)

[Derek Ortt]

it was not concluded that the surge is a function of intensity over the open Ocean, but more so due to the size of the 100KT and 65KT winds. The intensity offshore really only determines the height of the waves on top of the surge

[gatorcane]

a Katrina (at it's peak) into Miami would produce more than a 10 ft surge.
It's hard to argue how any of Miami would even be left.

[Derek Ortt]

No Chris, Miami Beach wont get more than 10 feet, even with a Katrina at peak. Remember, Cayman from Ivan at near cat 5 only had about 8 feet, and our profile is the same as Cayman, plus, the Bahamas break up the 50 foot waves (we may still get 30 though)

[gatorcane]

No Chris, Miami Beach wont get more than 10 feet, even with a Katrina at peak. Remember, Cayman from Ivan at near cat 5 only had about 8 feet, and our profile is the same as Cayman, plus, the Bahamas break up the 50 foot waves (we may still get 30 though)

Yes Derek you have a point and if there is any "good" news about a major into Miami, it's the fact there wouldn't be as much surge as say a major into Tampa

[MiamiensisWx]

A large storm (such as a repeat of the September 1947 storm) might have the greatest potential for the largest surge/erosion along the southeast Florida coast because of a huge size/windfield. Of course, another Andrew would create another large Biscayne Bay surge.

[zlaxier]

Does anyone have a SLOSH map of South Florida for Cat 3, 4, and 5?

10 feet maximum surge in Cat 5 for Miami Beach may be on the low side. The maximum may be more like 12 feet. This is because the massive 1947 Hurricane that hit South Florida apparently created an 11 feet storm surge on the Atlantic Coast in Palm Beach county and the shelf waters should be the same in Palm Beach as they are in Miami Beach.

Here is where I found out about the 11 foot surge in Palm Beach in 1947. It's from the NOAA site.

http://www.srh.noaa.gov/mfl/newpage/pal ... vents.html