I had a problem similar to this in my old car (98 VW Jetta) and found out that it was because there was water in the emergency brake line. Apparently when I would park the car with put on the ebrake it would freeze and get stuck even though the brake handle was released. Try parking your car one night without the brake on and see (if it is cold enough) if it does it in the morning again...if not that might be your problem. Good luck.