Originally Posted by Tourist in MSN

After several applications of Proofide, a natural water resistance is built up. That said, you still want to take care to avoid getting a saddle too wet. First photo below, I was on a group tour several years ago and one rider put his bike upside down in the evening so he could inspect the tires. Left the bike that way all night, in the early morning hours there was a big thunderstorm and his bike saddle sat in the middle of a puddle. By the time there was enough light for me to take the photo, most of the water had drained, but his saddle had been soaking for at least an hour, maybe two.

I use a waterproof cover. Some waterproof covers are not that waterproof. And sometimes I have instead used a thin plastic bag like a produce bag from a grocery store, those bags are pretty fragile so I used a non-waterproof lycra cover over the plastic to hold it in place.

When I apply Proofide, I have applied it top and bottom. I usually use fenders, but if you do not use fenders, you really want to apply it to the bottom to account for road spray. Second photo attached, I did not have fenders on this rainy day, I was glad that I had put Proofide on the bottom of the saddle. I have a waterproof cover on the bike in the photo although you really can't tell that from the photo.

I put a cover on it at night even if I think there will not be any dew.