Warping Cards?

[Jin]

I noticed that a select few of my cards have a slight warp to them (only the ones in magnetics.) I don't remember if they were like that when I got them so I panicked a bit and moved my cards to a cooler area.

Has this happened to anyone else? Is it the humidity or temperature that affects these cards? How/where do you store your cards?

thanks in advance

[Hornet21]

I find that any cards from 12-13 and 13-14 Elite I highly prone to this