As someone from SoCal, hella was always a NorCal colloquialism. I grew up around actual 'valley girls' and the associated slang, lots of silly things. Even after all of that, hella always sounded off to me.
I've always wondered where the terminology changes over. I think it may be somewhere around King City?
https://www.youtube.com/watch?v=-lc3peq4P5s&feature=emb_logo
As I recall, some of the questions were about well-known differences within American English, such as soft drink vs. soda vs. pop or sneakers vs. tennis shoes. But a few were specific to California and were intended to show differences between the dialects of the northern and southern parts of the state.
For example, to the question “If you’re going to the city, where are you going?,” most southern Californians responded “to a city” or something similar, while northern Californians responded “to San Francisco.” There might have been one or two East Coasters who answered “to New York City.”
Another question was “Name a freeway.” The northern Californians almost invariably gave a number (“101,” “5”), while southern Californians gave a name (“the Harbor Freeway,” “the Golden State”).
I moved away from California a couple of years later and have lost track of linguistic trends there. Have southern Californians shifted away from using names for freeways to using numbers?
You'll occasionally hear people call parts of (the) 101 the Bayshore Freeway, or 880 the Nimitz Freeway.
The big 3 freeways down here (405, 5, 101) are all referred to exclusively by number.
https://en.wikipedia.org/wiki/Southern_California_freeways#F...
While we're talking about the use of "the" with proper names, I've long been amused that, in most or all dialects of English, the names of rivers and oceans are preceded by "the" while the names of lakes are not: "the Nile," "the Indian Ocean," "Lake Baikal," "Lake Michigan." If anyone has an explanation for that, I would be very happy to hear it.
In that vein, SoCal uses "the" because "101 freeway" is the same pattern as "Indian Ocean", "101" is describing the kind of freeway you are talking about. No idea why NorCal doesn't do that; I blame brain damage caused by excessive fog.
My guess is that it’s a fuzzy boundary, and King City is the northern side of that fuzzy boundary. Great guess!
And looping back to the original topic, the title is:
Northern Californian English: Hella Different?
When all these freeways were given numeric designations, my theory postulates, people would still start referring to them by their old names, starting with the "the", but then saying the number.
Sorry, I slipped into my SoCal dialect there for a sec.