Oscarbreeder, I share your concern because that storm is heading my way.
You could wrap the tanks with blankets and close the drapes in the room to minimize heat loss. Maybe even put a few hotpacks between the glass and the blankets. I'd be more concerned about the 10 gal
tanks which will cool down much faster.
This may be a crazy idea, but if you had a deep tray that a 10 gal
tank could sit in, you could boil some water (if you have a gas stove), mix it with some cool water so you don't crack the tank, and pour it around the 10 gal
tank - a heated water jacket so to speak.
Hopefully, you won't be without electricity too long.