Yes, keep the temps up with an overhead heater potentially. However, that might also cause difficulty keeping the humidity up! I have found that Sphagnum Moss is a LIFE SAVER! I have said this a couple times before on here, I can't tell you enough how useful it is! Heat lamps will suck up all the humidity, but the moss will counteract that so your snakey can be hydrated AND toasty. You can buy a box of it from Petco/Petsmart for about $10, just use a couple SMALL patches (don't over do it) in the tub and follow the instructions on the box for soaking! The box will last you a couple months at least, depending! Good luck!
Good call I also should have mentioned this, I scatter it among the substrate, since doing this I only have to mist twice a week.