Last week I worked an aid station at a trail run and stood in the rain for 8 hours and went through 2 different rain jackets - Patagonia Torrentshell and an Arcteryx jacket. As expected, no typical outdoor gore tex (or some similar material) will keep you 100% dry all day. All those materials eventually wet out is my understanding.

So my question is are you aware of fully waterproof jacket that will keep you dry in a 10 hour rain storm? It doesn't have to be light or very breathable. It will only be used while walking or standing still. What do sailors use to stay dry in an all day storm?