Ike's possible storm surge

[Chris Hayes]

With Ike being a category 2 hurricane, I've thought it being weird that Ike could be on the way to producing a 15-20 foot storm surge. Is the possible large storm surge because of the storm's intensity or because of the immense size of the storm? I've thought of 15-20 ft waves being with a cat 3-4 hurricane, at least.

 

[Van DeWald]

I believe the increased storm surge is due to the very shallow waters off the Texas coast, and also because of the size of Ike.

 

[Lou Ruh]

Well, this is not an area I am an expert in, but, the model used to predict storm surge, the SLOSH model ( http://www.nhc.noaa.gov/HAW2/english/surge/slosh.shtml ), is claimed to be accurate to within +/- 20%. According to what I've read so far (which admittedly isn't much), that model uses:

* Pressure
* Size
* Forward speed
* Track
* Winds

This is used in combination with what is known about the "SLOSH basin" (where the surge is expected to hit, so, the water depth does also seem to be a factor) to come up with the surge estimate.

 

[Chris Nuttall]

Size of the storm is also a factor. That's a lot of water piling up for a long time. Take a look at the waves and surges being produced as far away as Biloxi, MS, and Pensacola, FL. The expected size of this surge has been noted several times by NWS and NHC as being unusual for only a Cat 2.

Things will probably get worse if the eye should make landfall south of Galveston and Houston. That will put the area in the NE quadrant. More water will just get pushed in there by the southerly winds.

 

[Matthew K. Hartman]

Since Lou mentioned it...

You can access Slosh output via FTP from NHC:

ftp.nhc.noaa.gov/surge/Latest

Not exactly sure on the naming convention on the .gif files, I just download the larger files to get the forecast loops. It appears "gl2" refers to Galveston Bay.

Enjoy...