We’ve had monsoons in southern AZ for as long as I’ve been here, and Ford was still in the White House then. Monsoons are actually a very specific type of storm system, which is why we have monsoons not humidity flow.
Not to be argumentative, but what is the storm system like then? From the way I’ve seen it used, it’s generally associated with humidity. It’s been described as hot humid air coming in from the South that contributes to thunder storms and flash flood type activity. I’ve seen it referenced that way for over forty years, not as a monsoon until recently.