Average daily dew point values observed this year in blue.
Traditionally the summer monsoon (summer thunderstorm season) would start when the daily average dew point remained at or above 54 F (the green line above) for 3 days in a row (that occurred on July 1 this year).
Dew point values fell below 54 F for several days in early August.  Dew Points were near 70 F at the start of the week (about as high as dew point ever gets in Tucson)