Hot dogs whether opened or unopened should always be kept in the refrigerator until you're ready to cook or eat them.
Never leave hot dogs out at room temperature for longer than 1 to 2 hours because they can start to go up especially when the temperature is above 90 F.
The hotter the temperature in the room the faster the hot dogs will grow bacteria and spoil.
When you buy hot dogs from the store you should immediately take the hot dogs home and refrigerate or freeze them right away.
Or put them in an ice chest to keep the hot dogs cold enough to prevent spoilage if you need to do other shopping but still get the hot dogs home as fast as possible and refrigerate or freeze them to prevent spoilage.