It doesn't seem to be that big of storm.
A cat 4 is pretty damn big.
It's the same size as Ike that devastated Galveston and Houston in 08 and at the cost of 37.5 billion in damages,which ranks third in damages from hurricanes in the US.
The categories refer to wind speed, not size. And in the warmth and shallow sections of the Gulf, TSs grow quickly, quicker than in the Gulf.
I know all about hurricanes given that I've been through around a half dozen in my lifetime.
And no they dont grow in the shallows they actually get weaker.
Deep warm water is the reason Harvy grew so fast and the shallow water along the coast is why it stalled out just offshore of Corpus.
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As a storm grows, it goes through a series of stages before being classified as a hurricane. It might start as a collection of thunderstorms known as a tropical disturbance. Then, with cyclonic circulation, wind speeds get faster and the storm becomes a tropical depression. If the wind keeps getting faster, the storm becomes a tropical storm and then a hurricane if winds are more than 74 miles per hour (mph).
The classifications are based on the wind speeds in the storm, not the size of the storm. Hurricanes that look small on radar can have very high wind speeds. And large storms can have low wind speeds. Wind speeds in hurricanes are often measured in knots. Compared to a mile per hour, knots are a little bit faster. Thirty miles per hour are about the same as 26 knots.
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Shallow is a relative term, the deeper the body of water, the colder the water.Gulfs are shallow compared to oceans and seas generally. I have lived no more than 1.5 hours from the ocean my entire life, usually closer.