Sunday's inaugural Pasadena Marathon was canceled because of smoke and ash in the air from several wildfires.
Race organizers made the decision at 4 a.m. after consulting with air-quality experts, as well as public health and fire officials. Runners were urged to check in with the organization's Web page on Monday.
John Parks, a member of the race management team, says organizers will meet over the next several days to reschedule the event.