Advice for moving with a bearded dragon?

I'm moving soon, but it should only be an hour and a half trip tops travel time for my beardy. (The process of getting him upstairs included) I'm a little worried since it's winter about said travel time. I plan on moving him to a temporary 20 gallon so I don't have to move his entire enclosure with him in it upstairs. To keep him warm I was thinking of using a rice sock/warm water bottle wrapped in a towel. But is there anything butter I should use? Maybe reusable hand warmers? Idk.