Cold Weather Traveling

What would be the best way to travel with a BP in a car in cold weather? The seller in Louisville is about 2-3 hour drive from where I live. Obviously, I'll have the heat on in my car, but I was wondering if I should make additional precautions.

My choice with smaller snakes has been belly heat from my belly lol, hold them aginst my body heat.

Secure snake in bag. Secure bag in plastic bin. Take your coat off and run the heat in the car. The snake will be fine.