Today Might Be The Formal Start of the Arizona Monsoon Season

Despite the current low humidity. But we'll see (from the National Weather Service in Tucson):

HERE IS AN INTERESTING MONSOON START DATE TIDBIT. FOR YEARS THAT END IN `6`...THE START DATE HAS BEEN CENTERED ON JUNE 28TH (1956...JUNE 28TH; 1966...JUNE 28TH; 1976...JUNE 28TH; 1986...JUNE 29TH; 1996...JUNE 30TH). SO WILL THIS TREND CONTINUE FOR 200(6)?