I keep bottles of water in my car. And gallons by my car to fill with. Anyone in the cold part of the county is probably having the frozen bottle in the morning I used to.

Solution. I have a plastic cooler in the garage and in it I have a coffee cup warmer. The cup warmer is 7 watts. I connected a metal measuring cup to it so the hottest part does not touch anything. The temperature stays about 40F.

Low tech.