As cool, wet weather continues to threaten Fiesta events, organizers of San Antonio’s annual citywide party hung the famous NIOSA Rain Rock on Monday to keep the rains at bay. Officials hung the stone — a tradition started in the 1970s by then-NIOSA Chairwoman Joanna Parrish — promptly at 10 a.m. The ritual began when a NIOSA volunteer informed Parrish of a Texas folk practice of hanging a rock with a hole in it to prevent bad weather.