While the term has been used for several decades in business names and catch phrases, the recent attention that Southern Hip Hop music has garnered has brought it into the limelight.
This term is claimed by several other regions as well (Chicago, Western Michigan, the Southeast), but it properly refers to Texas.
Chopped and screwed, third coast style.
2. Dude, I'm headed down Lake Shore Drive for the Third Coast Festival. You coming?
It is referred to as the Third Coast because politically and socially, it aligns more with coastal states than the rest of so-called "Middle America." It also shares a lot of physical similarities (such as beaches) which are commonly thought to only exist on the coasts.
Recently, residents of Chicago have tried to claim their city alone is synonymous with Third Coast. However, it actually refers to the entire Great Lakes region as there are a number of entities in the business and entertainment world outside of Chicago (especially in Wisconsin, Michigan and Ohio) that identify themselves as "Third Coast."
Some of the major cities in this region are Buffalo, Chicago, Cleveland, Detroit, Milwaukee and Pittsburgh.
(Please note that similar to how Philadelphia is considered East Coast even though it's not actually on the ocean, a city does not actually have to be on the Great Lakes to be considered part of the Third Coast.)
See Also: North Coast