So i have a Tiefling with resistance 5 to cold, electricity and fire. does this mean that he is resistant to the effects of the eternal winter. like making fort saves to avoid frost bite and hypothermia, or is that just for combat related, not climate related. just a curiosity, wasn't sure.
When you roll for temporary cold damage, anything under 6 HPs is ignored and you don't get hypothermia. However, if you take ANY damage then the other effects would take hold.
So in other words, you roll for it as normal and could possibly become fatigued from hypothermia. But it's very difficult.
I believe any cold resistance should make the PC immune to basic cold weather. After all, the resistance in this case prevents 5 points per round. The 1d6 is per hour.