longevity thoughts
Moisture is likely not a friend to longevity. It will cause curl problems in the long run, and mold if it is warm for long enough. So cool and dry is better, cool and moist is ok. Keep the paper sealed in the plastic bag it comes in - tape it shut after taking out a working supply of paper if it is a big box to start with. Putting a plastic bag over the cardbord box and then sealing the outer bag will keep the box paper from swelling and softening with time as it absorbs mositure from frost in the freezer.
Take the paper out and let it warm up before openning the box, if it has been cool stored.