On December 19th, I took this picture of snow on the Tehachapi Mountains while driving toward The Grapevine on I-5. I was heading to So Cal to visit family for the holidays. I've never seen the snow line this low here (although I'm sure the locals have seen it plenty). My educated estimate (using google earth and topo maps and comparing that to my photo) is that the snowline was at 2000 feet this day. My dad's family used to have a cabin above here in Frazier Park that they hand built themselves. I'm sure there were winters where they saw the snow much lower too.
The Tehachapi's are a "transverse range" (laying east-west) between the north-south running Sierra Nevada and Coast Ranges. I remember from a couple geography classes that the Tehachapi's may be the tail end of the Sierra Nevada but got bent northward due to movement of the North American and Pacific Plates so that they run east-west rather than north-south.