Originally Posted by
Lyle
The sylnylon doesn't absorb water. The pack cover does a decent job of keeping MOST of the water off of your pack. You cannot, however, trust it to keep everything protected. You still need to pack sleeping bag, dry clothes, electronics, etc in plastic bags. A rain cover is one piece of the barrier against wet gear, not your entire system.
A weak point in the new, modern, lightweight design of pack covers is that in heavy rain, they tend to collect water in the bottom. You need to periodically empty them. A PITA!. The old, formed pack covers like Kelty used to make for their frame packs, which were open on the bottom, did not have this problem. I plan to eventually put a couple of grommet holes in the bottom to allow drainage, but have never gotten around to it yet.