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This story was produced in partnership with the University of Wisconsin-Madison’s Investigative Journalism class taught in the School of Journalism and Mass Communication.

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• Recent wildfires in Canada and northern Minnesota brought a wave of smoke to Wisconsin in July, raising concerns in Rock County similar to those in 2023, when Beloit was ranked the city with the worst air quality in the nation.
• Rock County faces above average asthma rates, and air pollution from wildfire smoke combined with emissions from existing polluters can worsen these health risks. 
• The county relies on a particulate matter monitor in Rockford, Illinois, to track PM2.5 levels. Local advocates and community members are pushing for a regulatory monitor in Rock County, especially as industrial emissions increase.

Pablo Toral expected another successful summer field program at the Boundary Waters, continuing a tradition that has lasted close to 70 years. Instead, he found himself evacuating by canoe after wildfires forced his team to abandon the trip. 

Students had already started arriving at the research station for the program’s mid-summer session. They were supposed to spend the next month doing hands-on field research, canoeing and camping. Then came the evacuation alert giving everyone 20 minutes to pack up and leave. Toral, the chair of environmental studies and political science at Beloit College, said it was clear conditions were unlikely to improve, leading organizers to cancel the rest of the program.

After driving through the night, Toral returned to Beloit, only to find that the wildfires had followed him in the form of thick smoke and unhealthy air quality. 

Poor air quality is a serious concern for Beloit residents who worry about the emissions from nearby power plants and now wildfire smoke. Just three years ago, under similar wildfire concerns as this summer, the city was named the worst for air pollution in the United States.

Rock County also has above average asthma rates, making the poor air quality even more troubling for residents. 

Cristine Rameker, the Wisconsin Department of Health Services’ asthma program manager, told Wisconsin Watch that the most recent estimate of asthma-related hospitalizations per 10,000 people in Rock County — between 2022 and 2024 — was 39% higher than the statewide average, with a rate of 3.2 per 10,000 people compared to 2.3.

During those years, asthma-related emergency department visits per capita in the county were 23% higher than the statewide average at 34.2 visits per 10,000 people compared with 27.8 statewide. For children ages zero through 17, the average asthma-related emergency department visit is about 9% higher than the state average. 

The county ranked sixth-highest in the state for asthma hospitalizations and eighth-highest for emergency department visit rates between 2022 and 2024. Rock County is the ninth-largest county in the state in terms of population. 

In 2024 alone, data shows there were 138 asthma-related emergency visits among children in Rock County, or one every two-and-a-half days. 

Beloit School District data shows about 11% of students — 436 children — have asthma. Of those students, 110 have inhalers at school, while 326 do not have ready access to medication. 

Brittany Keyes, clean air policy manager with Healthy Climate Wisconsin and former vice president of the Beloit City Council, recalled a moment last fall when she was riding on a bus in Waunakee with a group of third grade girls from Beloit, including her daughter, after the girls finished their first 5K for a “Girls on the Run” event.

She described how the third graders had been training for months together, and now they were laughing, exhausted and proud of their achievement on the ride home. Until one girl began struggling to breathe. 

Keyes said a teacher was frantically searching through a bag for the girl’s inhaler — pulling one out, and then another. 

“She takes out a bag — nope, it’s not hers. She takes another bag — nope, not hers, not hers, nope, not hers,” Keyes said. “There were six inhalers for a group of 22 girls. … That’s not normal, and it doesn’t have to be that way, right?”

No particulate sensors in Beloit

Fine particulate matter (PM2.5), a type of pollution that is a combination of solid and liquid particles in the air, is a key concern for residents worried about air quality and asthma rates. 

Nick Mailloux, a postdoctoral research associate at the University of Wisconsin-Madison’s Center for Sustainability and the Global Environment, said a major reason why PM2.5 raises so much concern is its extremely small size — about 1/30th of the width of a human hair. 

Particulate pollution comes from a range of different sources, including power plants, vehicle emissions and industrial facilities — which Keyes and Toral both noted can all be found in Beloit. Additionally, Mailloux noted that wildfires are increasingly becoming a source of PM2.5 across the United States.

“A particle of that size is small enough that it bypasses a lot of our natural defenses,” Mailloux said. “These are particles that are small enough where they can pass through your airways and into your lungs, where then they can get into your bloodstream and cause inflammation that leads to lots of different respiratory, cardiovascular and neurological health harms.”

PM2.5 can cause new or worsened heart and lung diseases, along with a list of health effects like coughing, shortness of breath, fatigue, asthma attacks and more. 

While Keyes was still vice president of the Beloit City Council, she had read a 2021 report from Toral that found Rock County’s CO2 emissions increased by 325% between 2010 and 2019. After discovering that the emissions in her county were much higher than in counties like Dane and Winnebago, she contacted the Wisconsin Department of Natural Resources. 

She learned the agency operated one monitor for ozone on the west side of Beloit, and only for six months out of the year. She said DNR officials recommended community sensors, such as PurpleAir monitors, if she wanted to start monitoring for herself. 

PurpleAir makes sensors that actively monitor PM2.5, temperature, humidity and pressure, collecting air quality data and making it publicly accessible. 

Keyes said different nonprofits across Beloit participated in a community project to install PurpleAir monitors in the city in late 2022, using a U.S. Environmental Protection Agency community sensor loan program. Early data raised concerns, but the DNR told her that only five months of data had been collected, which is far less than the three years needed to establish an annual standard, Keyes said. However, that’s all the EPA could lend them for their study.

The group had secured funding during their time with the EPA’s loan to install three monitors in Rock County, allowing for continuous monitoring with data collected every 10 minutes. Now, Keyes said they have been able to expand their monitoring network to more than 20 PurpleAir monitors in the county.

“Our effort has really built awareness, and even the Rock County Health Department went after a mini grant … and they were awarded it, and they got 10 sensors, and were able to put them up at schools around the county, so now it’s not just urban centers,” Keyes said. “It’s super cool if you look at PurpleAir now, how we have a better distributed geographical monitoring system.”

Then in early 2024, technology company and global leader in air quality monitoring IQAir contacted Healthy Climate Wisconsin with alarming news — Beloit was ranked the most polluted city in the United States in 2023. The company had pulled data from the PurpleAir monitors through 2023 to draw that conclusion. 

What makes Beloit ‘pollution central’

Toral pointed to numerous factors — including an unusual amount of wildfire smoke from Canada that year, regional pollution from nearby cities such as Madison, Chicago and Milwaukee, as well as transportation emissions, nearby power plants and industrial activity — that all make Beloit “pollution central.”

He said bigger cities surrounding Beloit like Chicago, Milwaukee and Madison reported very high rates of pollution that summer exacerbated by the smoke. Toral noted all of those cities closely track their air pollution data. He pointed to the sensors Beloit has compared to other surrounding areas, saying through the sensors, Beloit was able to document where the smoke from the 2023 wildfires converged. 

“Unusually, we got winds coming out of the northeast, and that brought back the smoke from the fires in Quebec,” Toral said. “Those are what led to the perfect storm — very active fire season, dry winter, slow snow precipitation in the winter, low precipitation in the spring, leading up to the fires lasting longer, being more aggressive.”

He said that while Beloit is small, its monitoring is on par with bigger cities like Chicago and Madison. So, while Beloit was ranked as most polluted, he said there’s also a lack of data from other cities in that area of the state and northern Illinois to officially confirm if it’s Beloit specifically. 

“You don’t know how polluted you are until you test, and Beloit is very unusual in the sense that it’s a very small town that actually has very good air pollution sensors,” Toral said.

Keyes said the organizations involved in Healthy Climate Wisconsin’s air monitoring effort recognized the need for more coordinated action, so they formed the Stateline Clean Air Coalition — a group of organizations and community members who meet monthly to advocate for cleaner air and healthier communities. 

She highlighted that for more than two years one of the coalition’s primary concerns had been to install a regulatory PM2.5 monitor in Rock County — specifically in Beloit. While Beloit has an ozone monitor, Keyes said it’s not ideally located and only operates for part of the year. 

“(Ozone) is a harmful air pollutant, but not the most toxic. And what we’re really concerned about is particulate matter,” Keyes said.

Community members, health care professionals and advocacy groups also have shared their concerns with the DNR, urging a regulatory PM2.5 monitor in the area. Some argued that Beloit may have some of the highest PM2.5 in the state, with some estimates from advocacy groups and community sensors exceeding standards.

The DNR relies on data from a regulatory monitor in Rockford, Illinois, rather than direct measurements from Beloit. An agency spokesperson emphasized that Wisconsin meets the current PM2.5 standard of 9.0 micrograms per cubic meter, based on 2022-24 regulatory monitor data. 

The DNR spokesperson cited the EPA, saying the three-year PM2.5 design value for Rockford from 2022 to 2024 was 8.3 micrograms per cubic meter, with an annual mean of 7.3 in 2024 — below the requirement for a regulatory-grade PM2.5 sensor.

Craig Czarnecki, the outreach coordinator of air management at the DNR, emphasized that regulatory monitors are used for official decision-making and produce the most reliable data, while community sensors like the PurpleAir monitors are better suited for general awareness.

“Data produced using low-cost sensors do not undergo the same rigorous quality assurance and are known to be biased high when compared with data produced by regulatory monitors. These limitations make low-cost sensors best suited for qualitative purposes such as making decisions on daily activities considering the current air quality,” Czarnecki said.

Despite ongoing requests from residents and advocates to install a regulatory-grade PM2.5 monitor in Beloit, particularly near known pollution sources and in heavily affected neighborhoods, the DNR has not committed to expanding its monitoring. The agency stated that the existing network meets federal requirements. 

Czarnecki also noted the department lacks funding to expand monitoring beyond federally mandated levels.

Residents also raised concerns about the estimated 2.4 million metric tons of carbon dioxide emitted in Rock County in 2022, with about 2.1 million coming from power plants. The DNR spokesperson noted that CO2 is not regulated in the same way as pollutants such as ozone or particulate matter. 

Keyes said concern over emissions increased as Beloit’s energy infrastructure began to expand. She pointed to Alliant Energy’s Riverside Energy Center and the additions of the West Riverside Energy Center, a 730 MW natural gas plant. 

Toral said emissions data showed the Riverside Energy Center produced about 2.8 million tons of CO2 emissions the last year it was required to report in 2023, surpassing plants in higher-populated areas, which Toral said shows a “disproportionate concentration of pollutants in one single point.” 

Although multiple coal plants used to be in the Rock County area, and burning coal was worse, Keyes noted that natural gas, primarily the burning of methane gas, is still very harmful for the environment and the health of communities. 

“The fossil fuel industry has marketed very hard to make us feel like natural gas isn’t harmful. But it is. It is still a fossil fuel,” she said. 

Alliant Energy has since proposed and been approved to build a liquified natural gas storage and processing facility in Rock County to meet growing demand. Taylor Adams, the senior communications specialist for Alliant Energy, said in a statement that the location was chosen for its proximity to infrastructure and customers and that the project will comply with environmental regulation. 

“Rock County serves our largest concentration of natural gas customers in Wisconsin and is located near established pipeline corridors, making it a logical location for this type of infrastructure,” Adams said. “The proposed facility would incorporate multiple design features intended to control and minimize emissions.”

Adams said air quality impacts are currently under review by the DNR and will be available for public comment. 

Who’s affected

Toral called the situation in Beloit, a low-income community of immigrants and people of color,  “a case of environmental injustice.”

Toral noted the effects of pollution often fall most heavily on vulnerable populations, including children, older adults and people with preexisting conditions. He added that noise pollution can worsen health outcomes by increasing stress, disrupting sleep and weakening the immune system. 

“If you basically are living close to traffic, a power plant, a factory, anything that generates noise — that really exacerbates people’s conditions,” Toral said. “That makes the body more vulnerable to then have to cope with the pollutants.”

Keyes highlighted that Beloit previously had lower emissions than Dane County, but as Madison was able to retire some of its natural gas and coal plants, the regional demand for electricity resulted in power plants — and emissions — expanding in Rock County. 

Keyes’ daughter was one of 15 youth plaintiffs who filed a lawsuit against the Public Service Commission and state Legislature last summer over laws that prohibit the PSC from considering air pollution when reviewing permits for new power plants, along with a failure to protect the youth from climate change.

“Dane County has made progress, but the celebration of progress is really greenwashing the fact that we are suffering,” Keyes said.

New record, new norm

Air quality records were broken across Wisconsin July 16 as wildfire smoke from northern Minnesota and Canada was carried into the Great Lakes region by winds. Much of the state experienced hazardous air conditions, with Air Quality Index levels reaching their highest points in at least 16 years. 

The smoke brought back memories of the 2023 wildfire season, when similar conditions covered much of the Midwest. 

Toral said this year’s fires are following a similar pattern to 2023. He said because the Great Lakes form a basin, smoke tends to converge there, making Wisconsin “ground zero” for this contamination. He added that the current fire season is already very active, and while the fires were more severe three years ago, this year’s fires are closer to Wisconsin. However, he said it’s still too early to know whether this year’s fire season is going to be worse than 2023. 

“We thought that the fire season we saw two years ago was one of a kind — was very unusual — and here it is again, two years later,” Toral said. “This is a very unusual pattern.”

Wildfire smoke raises air pollution concerns in Rock County, where asthma rates are among the highest in Wisconsin is a post from Wisconsin Watch, a non-profit investigative news site covering Wisconsin since 2009. Please consider making a contribution to support our journalism.

As millions of acres burn across the western United States, some wildland fire veterans are fearful that aggressive fire suppression tactics ordered by the Trump administration — coupled with extreme, fast-moving blazes — could put firefighters in danger as conditions escalate this month. 

Those extreme weather conditions fueled disaster in Eastern Washington Saturday when a fast-moving wildfire jumped the Spokane River and swept through neighborhoods of Spokane, destroying more than 600 structures and forcing 60,000 residents to evacuate. Incident Commander Tom Clemo called the blaze “probably the largest, most destructive fire in Washington’s history.” 

No deaths have yet been reported in Spokane, but Mayor Lisa Brown told local journalists the city is “still assessing the potential for lives to be lost.”

Spokane fires destroy hundreds of structures

“There is not a fire department in the U.S. that can handle a wind-driven event this size,” said Spokane Assistant Fire Chief Lance Dahl to the Spokane Spokesman-Review. 

Leading up to this year’s fire season, federal officials with the U.S. Forest Service and the Interior Department directed their wildfire crews to use a “full suppression” strategy and attack wildfires urgently. Following a hot, dry winter that left much of the West parched, federal land managers said it was imperative to contain fires quickly before they get out of control.

But following several dangerous incidents, including the deaths of four federal firefighters in Colorado in June, some longtime wildland fire leaders are questioning that strategy. Many see it as a return to the Forest Service’s decades-old “10 a.m.” policy, which sought to suppress all fires by the morning after they were reported. 

While many states also adhere to “full suppression” policies that aim to keep blazes contained, federal officials have previously had more discretion to let fires burn under supervision if they’re not threatening communities. More concerning, wildfire veterans say, is the possibility that rhetoric from Trump administration officials is putting pressure on fire crews to use aggressive tactics to meet those suppression goals.   

Federal policies that sought to extinguish all fires quickly over much of the past century are now understood by foresters to be a major contributor to the current wildfire crisis. In many places, forests that used to experience fire at regular intervals have grown denser than historical norms, with trees competing for water and thick underbrush covering the forest floor. That gives fuel to the fires and contributes to fast-moving blazes.

“No one in the agencies have said it, but it sure looks like (a return to the 10 a.m. policy) when you read the directions,” said Jane Darnell, who has worked in administrative roles supporting wildfire response and spent more than 30 years with the Forest Service before retiring in 2020. “We lived with the 10 a.m. policy for 100 years, and we got here. This full suppression promise to the public is a promise that can’t be kept.”

Many wildfire leaders say they’ve seen extreme, unprecedented fire behavior this season that only adds to the risk of deploying crews aggressively. 

‘Full suppression’

In April, Agriculture Secretary Brooke Rollins and Interior Secretary Doug Burgum sent directions to agency leaders in preparation for the summer wildfire season. Both called for a “full suppression” strategy.

“Accelerate initial attack and use a full suppression strategy, in coordination with our interagency partners, across all land jurisdictions to suppress fires early and limit growth,” Rollins wrote. 

Burgum called for “prompt, decisive” suppression of fires, adding that decisions should be “balanced with firefighter safety and a clear assessment of probability of success.”

While both letters mention safety, some wildland fire veterans say agency leaders have put a clear emphasis on attacking fires aggressively. Some fear that crew leaders are being pressured to deploy close to the fire line, rather than choosing the safest place to make a stand. 

“I found it disturbing,” said Riva Duncan, a former wildland fire chief who served more than 30 years with the U.S. Forest Service. “You’ve got somebody in a suit in an office who’s never fought fires saying you’ve got to go direct attack.” 

Duncan serves as president of Grassroots Wildland Firefighters, a nonprofit that advocates on behalf of wildfire professionals.

In addition to the agency directives, wildfire veterans noted the rhetoric from President Donald Trump, who has threatened to impose tariffs on Canada as retaliation for wildfire smoke. 

“If managers and leaders are hearing from the politicos, ‘put them all out, put them all out,’ are we putting people in where we shouldn’t be?” said Bobbie Scopa, who had a 45-year career as a firefighter and now serves as vice president with Grassroots Wildland Firefighters. “I’m hearing from some young firefighters who feel like they are getting pressure to take actions. It’s stupid and you’re scratching your head and people are getting hurt.”

The Interior Department did not respond to a Stateline interview request. The Forest Service declined to comment, saying its resources are focused on fire response.

Dangerous incidents

Already this year, fire crews across the country have been involved in a number of dangerous incidents, including the tragedy in Colorado that left four firefighters dead after a fast-moving blaze overran their position. 

“We’ve already had nine entrapments (firefighters having their position surrounded by fire) this year. That’s crazy,” Duncan said. “That suggests to me that fires are moving quickly and growing so fast.”

Federal officials have said an investigation team is reviewing the Colorado incident. 

“I do trace the tragedy in Colorado to that policy that compelled them to go out and aggressively attack the fires even when conditions did not favor safety or success,” said Timothy Ingalsbee, a former wildland firefighter who now serves as executive director for Firefighters United for Safety, Ethics & Ecology, a group that advocates for ecological fire management. 

“This policy that compels crews to blindly rush out and attack all fires is just not smart and it’s very unsafe,” Ingalsbee said. “They’re throwing back to the policy of the 1930s, ignoring everything we’ve learned about fire ecology and fire behavior”

Other wildland fire veterans say they need to see more details before blaming the deaths in Colorado on federal strategy.

“It’s just really hard to connect that at this time,” Duncan said. “I have faith that the investigation team is looking at that.”

But many former firefighters decried the feds’ abandonment of “managed fire” as a tool. Under that approach, federal land managers in previous years have been given the discretion to let some fires burn under supervision, so long as they didn’t threaten homes or infrastructure. In those cases, advocates say, agency leaders recognized the ecological benefits of fire, along with the potential to reduce the risk of catastrophic blazes in the future. 

“The problem is not fire itself, it’s our relationship with it,” said Darnell, the retired Forest Service administrator. “We can work with these fires that are highly unlikely to have catastrophic effects on infrastructure, keep them on there until the weather puts them out.”

Ingalsbee, with the firefighter safety group, shared a similar sentiment. 

“Excluding fire from the landscape and attacking all fires, that policy ended in the ’70s because it was failing,” he said. “It’s performative firefighting, it’s failing to accomplish tangible goals and it’s putting lives in danger. Fire is nature’s recycling.”

State leaders respond

At the state level, foresters in the Pacific Northwest — the region hardest hit by fires this year — say they have not yet seen evidence that federal agency directives are causing firefighters to take more risks. 

Most state agencies are required by state law to suppress, rather than manage, fires. Oregon state forester Kacey KC said the state’s landscape is too parched this year to safely manage fires for ecological benefits. 

“Every fire we can keep small is good,” she said. “Especially in conditions like this, there is not good fire right now on this landscape.”

In Washington, state forester George Geissler said he had not heard of federal crews taking extra risks. But he cautioned that federal leaders should be careful of their rhetoric.

“If you set goals, but you don’t set a good leadership tone related to safety, you can have those type of decisions being made,” he said.

Geissler said the bigger concern this year has been chaos within the leadership of the federal agencies. Under Trump, the Forest Service and Department of the Interior have been hit with severe staff reductions. The Forest Service is in the midst of a major reorganization. And firefighting operations from multiple agencies within the Interior Department have been consolidated into the U.S. Wildland Fire Service, established by Trump this year without congressional approval. 

“In the past, you knew who to go to, you knew which position had what,” Geissler said. “Now with the rapid changes, the loss of personnel, it’s a little bit scattered.”

Federal crews aren’t the only ones that have been involved in dangerous wildfire situations this year. Two separate incidents in Washington state left firefighters injured as a fire overran their position. One of those incidents, the Lyons Ferry Fire, involved a Washington Department of Natural Resources helicopter crew. Geissler said that was a wakeup call for the agency that fire conditions are extreme this year. 

“When the weather is this bad, all of those (safety protocols) become more and more critical,” he said. “We did a full safety standdown over it, because that was an extremely close call for those firefighters.” 

Darnell, the retired Forest Service administrator, said she would not be surprised to hear of more incidents in which firefighters deploy their individual emergency shelters — last-resort devices that can save lives but do not offer full protection in extreme scenarios. 

“We’ve got conditions on the ground that are so explosive, it really begs us to be really careful about where we put people,” Darnell said. “I hope we don’t see any significant loss of life for firefighters.”

Stateline reporter Alex Brown can be reached at abrown@stateline.org.

WASHINGTON — President Donald Trump ordered 50% tariffs on several Canadian products Monday in response to what his administration describes as retaliatory restrictions on imports of American goods, including alcohol, dairy and automotives.

Trump’s three separate proclamations to impose steep tariffs on items like hockey sticks, wine and cement, came just days after he threatened to slap more tariffs on Canada as smoke from raging wildfires in Ontario blanketed much of the northeastern U.S. through the weekend. But a senior administration official denied the new tariffs were in response to the smoke.

“These are not the so-called wildfire tariffs. The president has asked for options on that, and options are being shared with him. These tariffs are in response to discriminatory treatment by Canada against U.S. products,” the senior administration official said on a call with reporters Monday afternoon.

The tariffs will go into effect Aug. 19.

Trump appeared alongside Canadian Prime Minister Mark Carney Sunday at the FIFA World Cup trophy ceremony in East Rutherford, New Jersey, but the two leaders did not discuss White House plans for the new tariffs, according to the senior administration official.

Trump triggered the new tariffs under Section 338 of the Tariff Act of 1930, a Depression-era provision that authorizes the president to impose duties up to 50% of a product’s value in response to discrimination against U.S. commerce. The provision has been long forgotten since the 1940s and has never been enforced, experts say. 

“To our knowledge, Section 338 has not been used for this purpose before,” the senior administration official told reporters. “It’s been on the books for a long time. In our view, the terms are clear: It gives the president this authority in situations where a country discriminates against the United States relative to the treatment given (to) a third country.”

Trump’s unprecedented sweeping tariffs on global goods, including from Canada, imposed in April 2025 under the 1977 International Economic Emergency Powers Act, or IEEPA, were found illegal and overturned by the U.S. Supreme Court in February.

The administration was ordered by the U.S. Court of International Trade to refund roughly $166 billion in duties paid by importers under the IEEPA tariffs.

Since the Supreme Court’s major blow to Trump’s trade agenda, the White House has sought other routes to impose tariffs. Almost immediately after the court’s decision, Trump announced a temporary base 10% tariff on all imports under section 122 of the Trade Act of 1974. Those tariffs are now being litigated in trade court.

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Wisconsinites breathed record-breaking levels of air pollution Thursday as wildfire smoke from northern Minnesota and Canada wafted across much of the Great Lakes region and the Northeast. Many monitoring stations across the state recorded pollution considered hazardous for the first time in at least 16 years — the span covered by most monitoring stations’ records.

As of 8 a.m. on Friday, Air Quality Index, or AQI, levels in Madison had peaked above 450 — far above the AQI’s 301 threshold for “hazardous” air quality, where everyone — not just sensitive groups — should take precautions to avoid breathing dangerous air. 

Milwaukee’s AQI reached 644 earlier on Thursday — more than twice the hazardous threshold. Air quality deteriorated even further in northwestern Wisconsin, with the index reaching 967 along the Minnesota border earlier in the day. 

Many Wisconsin communities, including Milwaukee, Waukesha, Odanah and Appleton, were still observing AQI over the 301 threshold Friday morning.

The index categories typically run only from zero to 500.

Thursday’s pollution surpassed levels once considered unprecedented. Before Canadian wildfire smoke pushed the AQI to record highs across Wisconsin in July 2023, cities including Madison, Milwaukee and Waukesha had not recorded an AQI above 200 since at least 2010, according to a Wisconsin Watch analysis of historical AQI data.

But wildfire smoke has elevated air pollution in Wisconsin each summer since 2023. Major cities have periodically recorded higher AQI readings around July, though Thursday’s levels were the first to surpass those recorded in 2023.

“This is a hazardous air quality episode that we have not experienced before,” Craig Czarnecki, air management outreach coordinator for the Wisconsin Department of Natural Resources, said in an email.

DataWatch: Wisconsin air pollution reaches record highs as wildfire smoke engulfs the state is a post from Wisconsin Watch, a non-profit investigative news site covering Wisconsin since 2009. Please consider making a contribution to support our journalism.

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Wildfires in northern Minnesota and Canada have caused some of the worst air quality on record for Wisconsin. The entire state remains under an Air Quality Advisory for fine particulate matter from wildfire smoke until noon on Friday, according to the Wisconsin Department of Natural Resources. 

As of 2 p.m. Thursday, most of the state’s air quality was in the “very unhealthy” or “hazardous” Air Quality category. That means that everyone, not just sensitive groups, should avoid outdoor activities, the DNR said.

In areas near Superior, the Air Quality Index rose above 800, while parts of eastern Wisconsin including Milwaukee and Kenosha measured above 650. National Weather Service meteorologist Benjamin Sheppard told Wisconsin Watch these levels are some of the worst on record. 

“What we’ve heard from some of our partners is that the Air Quality Index values that we’re seeing are definitely either never before seen or up there,” Sheppard said. “I’ve been working here for three years, and I’ve seen nothing anywhere near that high.” 

Index values in Wisconsin have exceeded the records set by wildfires in June 2023, DNR spokesperson Craig Czarnecki said in an email, noting that the figures “will still need to be quality assured.” At that time, levels peaked at 273, which means concentrations in Superior and the Milwaukee area have more than doubled. 

The U.S. Centers for Disease Control and Prevention recommends setting up a portable air cleaner or filter in a room that can be closed off from outside air and setting your air conditioner  to recirculate mode if possible or close the outdoor intake damper. 

Fine particulate matter, also known as PM2.5, is a main pollutant released from wildfire smoke that can enter the bloodstream. Dr. Joan Schiller, a member of Healthy Climate Wisconsin and retired medical oncologist, told WPR this can exacerbate lung conditions.

“I don’t think people realize how far away you can be from the fire itself and still have health problems,” Schiller said. “These health problems typically manifest themselves as respiratory problems, such as exacerbation of COPD or asthma or emphysema.” 

How can I check the air quality in my area?

The Environmental Protection Agency monitors the air around the country and compiles an air quality index, or AQI.

Here’s what to know about the index and how to keep tabs on your area, especially in U.S. regions dealing with smoke from Canadian wildfires.

What does the air quality index measure? 

The index rates how clean or polluted the air is each day. The EPA uses this measure to keep tabs on five kinds of air pollutants. The main concern from the wildfire smoke is fine particle pollution. These particles are tiny enough to get deep into the lungs. They can cause short-term problems like coughing and itchy eyes and, in the long run, can affect the lungs and heart.

What do the numbers and colors mean? 

The index categories typically only run from zero to 500 – although levels have reached well above 500 in multiple parts of the state. The higher the number, the worse the air quality. That range is broken down into six color-coded categories. Green or yellow — in the zero to 100 range — the air is pretty clear. Once it gets up to orange, the air quality could be a concern for sensitive groups like children, older adults or those with health conditions.

In the red and purple zones, the air quality is considered unhealthy for everyone.

And if the index gets to maroon — at 301 or above — pollution levels are hazardous.

At these high levels, take precautions to avoid breathing in the dangerous air. That can mean reducing your outdoor activities, running air purifiers inside and wearing a well-fitting mask like an N95 when you’re outside.

What’s the air quality right now? 

Check AirNow.gov, which updates every hour. The site shows a real-time map of the air quality across the country and also includes a forecast for the day ahead. The map pulls in measurements from a network of air monitoring stations across the country. States and cities may also offer more local guidance.

How long will smoke last in Wisconsin? 

According to Sheppard and the National Weather Service (NWS), a southerly wind on Friday means smoke is anticipated to retreat from west to east  – likely bringing an end to the advisory for much of the state. 

“With those southwest winds, the air is going to get kind of clearer and healthier in a southwest to northeast manner,” Sheppard said. “Areas further north and east in Wisconsin are going to be most likely to hang on to that smoke.” 

Areas along Lake Superior may also need to have the advisory extended, NWS said. But Sheppard said winds could bring back a second wave of smoke to the rest of the state as soon as Saturday. 

“The weather models tentatively are telling us that the second batch of smoke could be as strong, or perhaps even worse,” he said. 

The Associated Press contributed reporting, as did Hongyu Liu of Wisconsin Watch.

Wildfire smoke brings hazardous air quality in Wisconsin. Here’s how to stay safe is a post from Wisconsin Watch, a non-profit investigative news site covering Wisconsin since 2009. Please consider making a contribution to support our journalism.

The Minnesota Pollution Control Agency has issued an air quality alert for parts of Minnesota, including the Twin Cities metro area, for Tuesday through Friday, as wildfires in the northern parts of the state and Canada continue. 

Hot temperatures and poor air quality can aggravate pre-existing health conditions and pose risks to people with asthma, heart disease, high blood pressure and diabetes, as well as pregnant women and children. 

At extreme levels, smoke inhalation can lead to asthma attacks, heart attacks and strokes, so MPCA is advising at-risk Minnesotans to stay indoors. If you have symptoms, call your healthcare provider or 911 in an emergency. 

The MPCA advises against “vigorous” outdoor activities, like sports, which could exacerbate any serious health or lung effects. 

The Boundary Waters Canoe Area Wilderness in northern Minnesota indefinitely closed on Tuesday as more than 20 wildfires have broken out as a result of lightning strikes and dry air caused by the ongoing heat wave. Evacuations are currently underway in the Boundary Waters. At least 17 people have been rescued with no reported injuries. 

Smoke from the Superior National Forest is expected to head south over the next 24 hours.

Look for hazy skies as smoke moves across northeastern Minnesota to the southern and western parts of the state. 

Even for those without preexisting health conditions, hazardous air quality can lead to shortness of breath, irritated eyes and nose, coughing and chest tightening. 

Smoky air is expected in Brainerd, Alexandria, Hinckley, St. Cloud, Winona, Moorhead, International Falls, Two Harbors, Hibbing, Ely, Duluth, and the Tribal Nations of Mille Lacs, Prairie Island, Leech Lake, White Earth, Red Lake, Grand Portage and Fond du Lac. 

Hazardous levels of smoke are expected in Two Harbors and Grant Portage; the MPCA advises residents there to avoid any outdoor activities and stay indoors. 

For Minnesotans, climate change-induced smoky skies and poor air quality are becoming a near annual summer event; the state Department of Natural Resources says 2025 was likely the smokiest year in five decades or more.