The Monsoon Season begins Saturday in Arizona. However, even though the season will get underway this weekend, afternoon storms don’t kick into gear until around the Fourth of July. The National Weather Service predicts a later than usual start to season this year. Forecasters predict the season could get going in mid-July. They also predict it could be a hotter, drier season than normal, but an active Pacific hurricane season could affect Arizona later in the season. The Monsoon Season officially ends on September 15th.