Northern vs Southern California “Hella” word

Will is a 20 year old kid from Carmel, California, which is in Northern California. He was born and raised in the same spot and never really travelled. He said that California being such a large state, there was quite the rivalry between Northern and Southern California. He even said there were some terms that only Northern California said. The specific term he talked about was a form of slang, the term is:

“Hella”

Will described that only Northern California’s use this term in sentences, and if one was to use it in Southern California it was “social suicide.” I asked him to use it in a sentence and he said “Oh, um, your shirt is hella red.” He said it is just used as a term to intensify something. I find it fascinating that there is a slang term that is allowed and used frequently in Northern California, but banned in Southern California. I just assumed it was a common slang term that everyone knew, being that I used it when I lived in Washington, so I find this California rivalry fascinating.