No matter if it's Hot, Warm or Cold you should Always check your POI, it would if anything give you a Pice of Mind to know for sure where your at. I dont care if I sighted in when whatever Temp it was, befor I go Hunting Im checking to make 100% Sure Im where I shoud be.
But I have also Hunted on some Pretty COLD Days and I still hit where I was aiming, and I know for a fact that I did'nt sight in when it was Below Zero out. So with that said it would be Impossible to know exactly for sure where your gonna hit when the Temps vary so much, just check it befor your Hunt and that's all you can do.