I almost always pitch a tarp over my tent, but not down close to it (above the tent roof 2-3 feet).  It keeps the tent in the shade and dry if there is a sudden rain storm.  If I think it will rain eventually or overnight I tie rope to various rocks/branches where it will need to be if I do have to snug the tarp down to stay dry.  Then if I have to get up in the dark it is a quick project to re-tie the tarp for a storm.