Succulents are plants that hold water to be used later on. They are not a family of plants. Many types of plants have succulents in them, but not all plants of a family necessarily are succulents. In Tucson many of the plants that we refer to as succulent do not do well in our intense sun.
In most years we have an adequate amount of rainfall during the monsoon season. The summer of 2013 was an exception. The only good thing that happened with the little amount of rain was the lack of weeds. There were some, of course, but not the amounts of previous years.