Every state has its own culture and a lot of that can be seen in the way we talk to each other. While slang words come and go, some stick around, and others never leave their home state. Matthew J.X. Malady from Slate enlisted the help of linguists, friends, readers, and online message boards to try to figure out what words distinctively belong to one state. After a lot of arguing, Slate's list was complete and ready to be beautifully illustrated by Lisa Larson-Walker.
While this is by no means a definitive list, it seems like a good jumping off point. As a New Yorker, I can confirm that "mad" is very accurate. Head over to Slate to see the full list and play with the interactive map.