For most of my trip to Colorado and back it rained. The way back it rained a lot. In high winds and rain I never had an issue. Like others, my truck rocked sometimes from the wind, but it was never a problem.
I actually found it to be an advantage, especially on my last stop on the way home. I called the closest KOA to me to rent a space as I was getting too tired to continue to safely drive. I asked for a spot and she said had plenty open, but they were all flooded. I told her I would take whatever she had and not to worry about the flooding. When I pulled in at 10 at night in the dark it was absolutely pouring and the site had probably a foot of water. The RV folks on higher lots were sitting under awnings looking on wondering what I was going to do. I had that tent set up and was high and dry in ten minutes. Everyone with a ground tent had to pack up and sleep in their cars for the night and then pack up soaking wet gear the next morning. Needless to say I had a few people asking about the tent the next morning.