I was just wondering, as one of my characters lived there. If it does, how much does it snow and what is the average lowest temperature?
I've lived in the San Fernando Valley (in LA County) since 1996. In that time, I've seen snow (enough to whiten the ground) at our house once, and it lasted about three hours.
I highly doubt it. I happen to remember watching Mythbusters and one of them mentioning that snow was very rare in the San Francisco valley, which is several hours north of LA.
When I first moved to Washington, DC (from Colorado, where it snows), I had a good friend who had just moved to town from L.A. The first time we got minor snow flurries - little stuff that didn't even stick to the ground - she ran out of the building and starting frolicking in the street saying "It's SNOWING!!!" She'd never seen snow actually fall before. (She had seen snow on the ground during ski trips to the California mountains - but never seen it fall from the sky)