I kept blue jackaroo in my folks driveway for a year now and if anything she had dried out in bad area. Decent heavy tarps are a must and the ebay cheap ones will fall apart after a time. We would during a few big storms tie her down with the eyelets then run ropes over the top to prevent it lifting. Some long lengths of wood rolled up along the edges works great too.
From my experience the wood acts more like a composite and is fine being dry. I am stripping mine back and most of her is in mint condition other than small patches of fluffy wood which is I assume some kind of dry rot. You can knock on the side of the boat and hear hollow area which i had a few that I filled with epoxy.