I was in a storm once and the campground owner came around to the sites and told the people to park their cars right next to their rigs, on the side the wind would be coming from. The theory was that RVs are built to allow wind to go under them and that's what tips them over and parking a lower car next to them partially stopped that. Most of us did what he suggested and had no problem. Some did not and the next morning they were strewn around, with their wheels up. Something to try anyway. Might make a difference. I hope you don't have to find out and the suggestion to get out of town, if possible, is your best move I would think.