HunterGatherer
WKR
What about using something like a silicone spray to make your existing covers more water resistant? I’m sure most waterproofing products like DWR aren’t rated for high temps…It no longer remains simple and lightweight.
To get waterproof. It has to be something like silicone. I did a whole bunch of testing with silicone wrap.
I can tell you how to buy stuff to DIY or I guess sell kits for it.