Oh boy, can I tell you about humid environments. Even in an enclosure, I had the filament swelling inside the extruder enough to jam it. 80-90% humidity during the summer down in my basement.
That problem is tamed, though. Here is what I did:
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homebuilt enclosure (absolute must), with rechargeable silica dessicant packs inside during the really humid season. Keep in mind this does not have to be a perfect airtight climate-controlled environment - it just has to be a box that discourages airflow, like any enclosed space
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filament in a dryer box (basically just a tall tupperware container) with a bowden tube going to the toolhead
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inline filament dryer (Thorsden) in between the dryer box and the enclosure
Now, this is a bit pricey (especially the filament dryer) and might be a bit overkill, but it absolutely worked under what are probably the worst conditions short of being actually underwater. The big downside, aside from the price of the Thorsden, is the need to fabricate a connector for the bowden tube on top of the toolhead. I machined mine from steel on a lathe, because I do things like that, but I’m pretty sure there’s a 3D-printable version. See https://forum.snapmaker.com/t/my-enclosure-project/20013/31 for the discussion.
If I were to do this again, I would probably go with a bit less overkill. A decent dry box, such as https://www.amazon.com/gp/product/B0BFQXHRV5/ (yowch, that ain’t cheap anymore either, but you get the idea), a $150-200 humidifier in the room (you probably want that anyways), and bowden tube going into the enclosure but not necessarily connected to the toolhead should suffice.
With 65% humidity you could probably get by with the tupperware-and-bowden approach, foregoing the electric drybox or the inline filament drier. Definitely get some silica packs such as https://www.amazon.com/gp/product/B07SRDMNRC/ and a cheap food drier such as https://www.amazon.com/Commercial-Chef-CCD100W6-Dehydrator-Preservation/dp/B075ZB3V9S/, which you can use to recharge the silica and to dry the filament rolls before putting them into the tupperware.