Southern California got ready Monday for the first storm of the new rain season, due midweek, while also preparing for possible debris flows as the threatening remnants of tropical storm Rosa rolled through the mountain and desert areas. For a time Monday afternoon, authorities issued a voluntary flood evacuation for San Jacinto Mountain communities in the area of the Cranston fire that burned near Idyllwild as Rosa’s clouds headed north from Baja. That voluntary evacuation notice was lifted early Monday evening.