You have a panther , right?
It's best to not let the temps fall below 60F at night. But, even for this low you have to let it happen gradually, not just from 70 at night to 60 all of a sudden (this is not hard to do with temp changes, you just have to watch if the hydro goes out in winter and your house is freezing.)
I live in Ontario, Canada, so you can imagine that I know about cold winters, lol. I got Orion in Feb last year, and I had a LOT to fix with the lights and humidity during the winter months. This is the set up i decided on. I will explain it, and you can get info from it that way, and use whta you think will be good for you! 
Ok... lighting/heat first. I first had one light for basking and one for UVB. Orion was just a baby, so she didn't need the temps as high as she does now. i soon discovered that she needed ANOTHER heat light, b/c her basking spot just wasn't staying up high enough. Right now I have a MV bulb floodlight. I am going to be using it for the main light and for the ambient temp - you will want it to be about 80-85 throughout the top and above 70 in the bottom - and then a 75W spotlight for basking. The spotlight is good b/c you can get a nice high basking spot - about 90 is what i use- without the ambient temp being too high. then, if you still have a problem with the ambient temp you can add another flood, of 60W. This is one that you can turn on on really cold/drafty days, but you may not need it on all the time. Also, you will probably not need a night time heat lamp unless you keep your house cold. Room temps of around 65-70 are ok for panthers at night.
Humidity: I wasn't expecting it to be a problem. I didn't think about the heater frying the air, lol. So... to begin with I had a fogger and a coolmist humidifier. This was NOT enough... So, I ended up getting a warm mist humidifier also. The warm one goes close to the cage with the cool one behind it. I have metal air ducting thingy's with elbows pointing into the cage. The coolmist's elbow is about 8" and the warm one is about 5". The cool air then blows the hot air into the cage for a nice humidity that isn't too cold (I also found the coolmist was bringing down the temps way too much on it's own)/
Yes, this is a lot. Lol, i had a fun and experimental winter, to say the least.
The two humidifiers are lots on their own, but if you find it still a little dry, then you can have a fogger on a timer. Just play with the times a bit, and you'll find sometjhing that will work.
Lol, I know this is a lot. I worked on it a lot. If you have any more ?s just ask!