I'm going to drive from the south bay (Sunnyvale) to Palm Springs on Tuesday, Dec 22. Given that it is a weekday and I want to avoid LA traffic, and also to avoid possible closure of I-5 at Grapevine as it happened a few days back, this is the route I have in mind:
US 101 -> CA-152 -> I-5 -> CA-46 -> CA-99 -> CA-58 -> CA-395 -> I-15 -> I-215 -> I-10
Although this is only 20 miles longer and has long stretches on highways rather than freeways compared to the direct route of US 101 -> CA-152 -> I-5 -> I-10, I'm thinking this will end up being faster.
However, I haven't driven any of the following routes and so I'm just speculating: I-5 south of the CA-46 intersection until the I-10 intersection, I-10 east until Palm Springs, and CA-395 from CA-58 to I-15.
Please let me know what you think.