With pipe tobacco, the only real no-no is to let sealed tins get too hot. So try to keep your tins at room temperature, whatever that is for you. In the summer, you may want to keep everything in your basement.
I'm not sure what a good humidity for pipe tobacco is! Everyone has their own opinion. Regardless, as tiltjlp stated, you want to keep the tobacco sealed in tins or jars. As you gain experience, you will find that pipe tobacco has incredible resilience. I have had an open tin in my car for months now. The tobacco has endured whatever climate the car has thrown at it and still burns and tastes fine. Usually, if it dries a bit, just flick a few drops of water into the tin and put the lid back on. If it seems to wet, I leave it in the pipe for a few hours before lighting. It's really touchy-feely!
So what we're getting at is, you don't have to worry about the environment as you would a cigar.