Fraizer park might be the closest ( I-5 north Just before you get to the grapevine) beware ... if it rains here, it s snowing up there.. AND the CHP will close the freeway, even if you have chains ..I lived there for a year but the jump in gas prices forced me back to the valley :-/angeles crest highway might be another option but because of the fires this past summer, there might not be too much left to see as far as foliage.
There is Frazier Park and/or Gormon. It is conviniently off the 5 fwy once you pass the Valencia/Santa Clarita area. This week they are recieving a large amount of snow so there will no doubt be snow once you go there. By the way, you made a great choice living in Northridge, one of the great parts of the valley to live in. Hope you have fun at your snow trip.
WoE nailed it. Either Frazier Park or go up Angeles Crest Highway. Frazier Park is a bit further, but a lot safer. Take I-5 towards Castaic, and head up the hill past Gorman.