DETROIT — Wildfire smoke cloaked Metro Detroit on Thursday, creating a thick haze after traveling hundreds of miles from Ontario and northern Minnesota, where raging wildfires are sending a cloud of ash into the air.

The haze, which was so thick that it made visibility difficult in some areas, impacted everything from outdoor day camps to concerts in southeast Michigan. Health officials urged residents to be cautious and stay indoors if possible.

The air quality in southern Michigan reached levels so toxic Thursday morning that it was considered an "emergency condition" by federal environmental officials who warned everyone could be impacted, especially children and people with asthma or other respiratory conditions.

It was even worse in the central Upper Peninsula, where Marquette County Emergency Management Coordinator Brian Hummel said ash fell like snow flurries on Wednesday and Thursday.

"I had a layer of ash on my vehicle yesterday morning when I was leaving home to come into work," he said. "This is my first time experiencing something like this."

The conditions will last through Friday, according to a Thursday morning update from Michigan Department of Environment, Great Lakes and Energy meteorologists. How long it persists after that is "the big question," they said.

"Our best model for smoke only predicts out to 48 hours," the meteorologists said. "That model is currently showing improvements on Saturday, but it is likely that smoke will linger and recirculate for a while. The National Weather Service mentions the possibility of rain on Saturday, which would help. The Friday forecast will shed more light on that."

The best way to stay safe is to stay inside with the windows closed, said Kathleen Slonager, a nurse and executive director of the Asthma & Allergy Foundation of America Michigan Chapter.

Running air conditioning units and indoor air purifiers help clean indoor air, she said. If people go outdoors, they should wear a high-quality mask that is at least an n-95.

People who have asthma and other chronic health issues are especially at risk of exposure to the smoke in the air, Slonager said.

"It can really narrow those airways, inflame the airways, put all that gas and particulate matter (in your body) as well," she said.

Smoke causes cancelations, closures and a free gym offer

The lingering smoke forced communities across Metro Detroit to adjust their operations. Some day camps either canceled their programming for Thursday or shifted it indoors.

Royal Oak Schools said Wednesday that its summer programs will be held as planned on Thursday, but students and staff will remain indoors throughout the day to reduce exposure to outdoor air.

"Our buildings are equipped with HVAC systems that provide filtered, climate-controlled air, along with UV filtration technology that helps further treat the air circulating through our schools," officials said in a statement on the district's Facebook page. "Program participants will receive additional information from their program directors via email."

Monroe Public Schools officials, meanwhile, canceled summer school classes and activities at its Knabusch Center on Thursday due to pollution levels from the wildfire smoke. They said all athletic programs are also canceled, but the district's Riverside daycare remains open.

Overnight camps such as Interlochen Arts Groups, meanwhile, said they are closely monitoring the air quality conditions affecting its area and adjusting programming accordingly.

"The health and safety of our campers is our top priority," the group said. "We are moving activities into air-conditioned indoor spaces whenever possible, limiting outdoor activities, modifying schedules as conditions warrant, and making masks available to anyone who requests one.

On Thursday, Planet Fitness said all of its Michigan locations were opening their doors to anyone wanting to exercise indoors for free and with no obligation to join through Sunday.

"With recent alerts due to the Canadian wildfires, we want to make sure those who normally exercise outdoors have a safe option to avoid unhealthy air quality levels," Sarah Wilson, director of marketing of Impact Fitness Group, a Planet Fitness franchise division, said in a statement.

Waterford warned that Priority Waste's trash collections may be delayed because of the smoke.

Warmer world fuels wildfires

Wildfires are clearly worsening as the climate warms, said Slonager with the Asthma & Allergy Foundation of America Michigan Chapter.

"I've lived here in Michigan for over 40 years and never, until last summer or the summ before, never have we ever had any issues like this," she said. "And now, it's like regular occurrence that we're getting these wildfires happening more intensely. Everything is much dryer, the wildfire season is lasting longer and we’ve got to tie it back into climate change.

"It’s a public health issue, plain and simple. This is a public health issue, it's not political."

Wildfires are becoming bigger and harder to control as the atmosphere warms, said Jonathan Overpeck, a climate scientist and University of Michigan climate and energy professor.

That's because warmer air sucks more moisture out of the ground and out of trees and other plants. That dries them out and creates more fuel for fires. In turn, those fires release carbon dioxide, which exacerbates human-caused climate change, Overpeck said.

"The situation, as it gets warmer, will continue to get worse faster," Overpeck said. "We've got to just stop burning fossil fuels, the natural gas, coal and oil."

The largest increase in extreme fires have taken place in the western U.S. and northern boreal forests of Canada, according to NASA. NASA scientists who reviewed the agency's satellite data found extreme wildfires became more frequent, more intense, and larger from 2003-2023.

Wildfire smoke contributes to asthma, heart attacks, dementia: researchers

The smoke is more than unpleasant. It's dangerous. It has tiny particles that are small enough to seep into people's blood and damage their lungs, hearts and brains. Exposure to the pollutant, called fine particulate matter, can trigger asthma attacks and other breathing issues.

It gets worse. When wildfires tear through communities, they burn trees and shrubs but also gas stations, homes, factories, cars and anything in their way. That creates a "toxic soup" that University of Michigan epidemiology professor Sara Adar said can lead to early death, trigger asthma attacks and contribute to dementia.

Exposure to any kind of fine particle pollution is associated with greater rates of dementia, Adar wrote in a 2023 investigation in the journal JAMA Internal Medicine, but researchers have found that the link is particularly strong when those particles come from wildfire smoke.

"Our brains are incredibly sensitive to how much oxygen we get, the pumping of the blood," Adar told The News last year. "Anything that's going to damage the blood vessels, which is part of what causes heart disease …, is going to damage the brain as well."

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