A little storm blew through here today. The side ways rain was incredible with tornadoes touching down all around. The walls/windows of my house were soaked to a height of 7 feet, even though they were protected by an 8 foot high ceiling that covered them for a distance of about 10 feet.
Even if I had a full storm pitch with a 13 foot tarp, it's hard to imagine that things would have stayed dry. It was amazing to watch the trees whipping back and forth like crazy, just shy of breaking. Even if coverage had been adequate, I would be surprised if a stake didn't pull loose, or a cord snap or the tarp rip under the force of these winds today, even 1/2 mile away from where small tornadoes actually touched down.
Of course, if you were hanging from ( or tent camped under) one of these many trees that the winds/tornadoes snapped and then carried 20-50 feet through the air, I suppose getting wet would be the least of your worries, eh? I mean, compared to being crushed or impaled by the tree.