Where in Northern CA? DH is from some tiny little place up in the mountains, not far from Bodie, IIRC (he's a Native Son of the Golden West or something like that)
Ah, yes, that's quite a way from me. I've lived my entire life in the San Francisco Bay Area.
yeah, that's way out there. Bay Area native here too...and there are
slight differences between the Northern and Southern California dialect, but they're slight. Also slight differences in inflection, intonations, etc. Southern California girls tend to be uptalkers - every statement seems to end in a question mark. Southern California boys tend to be downtalkers and extend vowels, like Southern California's trademark, laidback, "Duuude," rather than NorCal's more clipped, "Dude." I found that when I moved from the Bay Area to SoCal, my intonations and inflections shifted south with me. When I moved back to the Bay Area, my Bay Area "voice" came back with me and I started using words like "hella" again, which would get me blank stares when I lived down south, although it's become a more widespread expression (ie, "That's hella (hell of) cool," instead of "wow, that's really cool!") nationwide as I've heard people in other regions using it. I want my word back!
Despite not being born and raised in the San Fernando Valley, though, I can sound pretty Valley when I want, which isn't often unless I'm flirting with a guy from out of state (and sometimes with Bay Area natives like my Paulie). They find it hysterical - and so do I.

oh, and as for the flat, accentless, affectless "news anchor" speech pattern? There's a name for that - Broadcast English.
And my Seattle-born-and-bred friend says "WaRshington," whereas California-native I say, "Washington." So who's the native Washingtonian now?

He also calls soda "pop." It's "soda," dang it!