You are correct: Stay with the car. A big car is easier to spot from the air than your little body. It's also, at the very least, some form of shelter. It might not be as warm as you'd like, but it's still warmer than a snowdrift; especially with more than one person inside. There are also things and materials in a car that can be used to signal rescuers. Tear a mirror off and you have a signal mirror. Cut the spare tire off of its rim, toss it into a fire (that you started using the car's lighter), and you have a nice, smoky signal fire.
I hope and pray that I'm wrong, but I think that they're gonna find this poor guy deader than dead; if they find him at all.
No further information at this time per local television.