I keep 10 assorted cans of food along with 12 bottled water under the shell of my truck. Where I park is secure enough that I can keep the sliding windows open. That definately helps to keep temps down over what you might get inside of a sealed-up car. I also keep it stored in a large soft-sided cooler which should help eliminate wild temperature swings. I rotate it every October and so far have not had a problem with eating it.

Regards, Vince