Posted By:
davidcycebackYour storage conditions might attract polar bears, and that's never good.
I grew up in Wisconsin and my cards were stored for many years in a closet that got below freezing many times, and the cards were undamaged. While I wouldn't recommend storing cards below freezing, I have no proof that below freezing wrecks cards. If the cards are generally lower grade, the cold may not be a big deal.