Yeah, it’s -11F/-24C right now and the humidistat is saying it’s 22% right now. Usually, in the summer time humidity ranges from 50% to 75%. But I have stored filaments like PLA and even PETG open on a shelf without care for over a year. Even now, the boxes they are stored in are now air tight.

I have never need to dry PLA and I do dry PETG occasionally if I really need that super clean print. Otherwise I just either manually remove the slight stringing of the PETG or I totally ignore it. I do keep a spool of TPU around and I do dry that before use. But it seems to holds up well for several weeks just hanging on the printer.