Power outage and fish tank...?

My power went out around 8:00 p.m. last night because of all of the snow we got, I live in upstate South Carolina. It is still out right now and I am worried about my fish, I have a 56 gal with mostly tropical fish. Do you have any suggestions on what I should do to help my fish survive? I am considering moving my more expensive fish to my sisters house, she still has power. I don't know how long we might be without power.