Phillip Pantuso reports for the Times Union that the state Department of Environmental Conservation issued a ground-level ozone warning for Dutchess, Orange, Putnam, Ulster, and Sullivan counties and the New York City metro area, which includes New York and Rockland and Westchester counties from 11 a.m. through 11 p.m. July 6. This time though, smoke from Canadian wildfires is not blowing this way. Instead, the summer heat is leading to more ground-level ozone from automobile exhaust and out-of-state emission sources. Ozone is produced indirectly when sunlight chemically reacts with nitrogen oxides and volatile organic compounds from automobile exhaust and industrial emissions. The DEC recommends young children, those who exercise outdoors, those involved in vigorous outdoor work, and those who have a respiratory disease such as asthma should consider limiting strenuous outdoor physical activity and stay inside. Read more about this story in the Times Union.