The dark red areas on this map are excessive heat warning areas.
They just happen to correspond to the desired location of a deep thermal low that would assist the moisture flow to the Flagstaff area. As many people have said, it really has to get hot for the monsoon to really kick in. It has been getting progressively warmer the last few days. At the same time, dewpoints have stayed mostly in the 40’s. The next few days will be mostly dry with plenty of big puffy clouds, but things should change by the weekend.