We love Scottsdale and have always visited in September before as the airfare is normally a bit cheaper then, plus the hotels and all the children have also gone back to school making for a more relaxing holiday. As we will both be retired by next May, my question is which will be the best time to travel - May or September? Will the weather be hotter in May as we usually find the September weather just about right for us although it can be still very hot (to us!) that time of year. We can also visit for longer then our normal 2 weeks but if it's normally very hot in May then it will have to be September once again.