of or pertaining to the condition of being dry and hot: a xerothermic climate.
adapted to an environment that is dry and hot: a xerothermic organism.
I looked up all the words that start with X. This word seemed to fit PhoeniX "to an X" - being dry and hot .... yep, that's how it is here. I would think the easiest job in PhoeniX would be a weatherperson. "And how is the weather today?" Dry and Hot! We are Xerothermic!
Check out the other X's on Monday at:http://unglazed.blogspot.com/