<p>I have a Jansport and it’s proven to be more or less water resisitent. Things were slightly damp when we were getting rain at about 3 inches an hour (sadly that’s not an exaggeration), but other than that I’ve been fine with it. It has <em>sort of</em> of plastic-y lining on the inside. I’m not sure how else to describe it, other than the backpack itself is not just straight fabric
For now, if things are getting that wet, just throw a plastic bag in there that you can slide your stuff into</p>