I have a thermometer with remote sensors (any kind will do) and I keep one in the water bay so I can see the temperature differences. You could experiment even before you left to see the differences.
My coach does have heat (furnace duct) into the basement. But on one occasion I had furnace trouble so I was able to use a small electric heater in the water bay and it kept things nice and warm and one in the coach to keep us warm.
Always have fresh water in your tank in case the faucets in the RV park freeze (happened to us). Or they could have a break and turn the water off.
Watch your propane level and make sure you order before you get too low---just in case. Propane delivery is very busy in those condidtions.
And have fun, we did.
I do all my own stunts
03 Dolphin LX 6355, Workhorse W22, 8.1 vortec, 04 CR-V, Blue Ox, Brake Pro----Norm, Barb and
Doc(He's a PhD)