You need an ice chest or sturdy styro-foam box (like food is shipped in) to hold in the heat when using temporary shipping-type heat packs, just in case
your power is out. Snakes travel very well actually...use a pillow case & bring a few spares; use a sturdy wire twist-tie around the open end, then fold
that part over on itself & secure snugly with a rubber band. I've never had a snake escape this way, and it's much easier than trying to tie an actual knot
in a pillow case. I've moved cross country with snakes (in ice chests) and I've gone days without power in bitter winter cold during an ice storm this way
and my snakes were fine...actually "happy campers". The only difference was that I used jars of hot water to keep the ice chests warm, as I didn't have
heat packs at that time...but I did have a gas hot water heater. All my snakes (about 15 at that time) seemed very relaxed in their own pillowcases and
none became sick after the fact.
Don't panic, just prepare the best you can. Fingers crossed for you & everyone in the path.