Here's what I do personally with my B&W films.
I keep most of my NEW films in ziploc bags and in my refrigerator.
I keep some in my closet so I can use them right away.
Once exposed, they stay in room temperature.
I always try to finish my roll per shoot/outing but not always successful.
I NEVER even thought about temp variations in a roll. But I would think, if you are coming from/going to extreme temp variations, you might want to wait until temp equalizes before you do anything with them. Condensation can ruin a lot of things. Other than that, I don't think I'd care too much. Yeah, I would leave film in my camera with no concerns. Just not shoot with it right away.