Can I leave my car there for approx 12 hours?

If you put a note in windshield it's ok to leave car for 12 hours.

If you're going to leave there for about 12 hours put some kind of note on the window there so the cops don't think it's abandoned alright and if it's a rest stop that has a restaurant they may think when they came in and check it and think you're in there but I would leave a note on the dashboard that you would be back in 12 hours to be on the safe side