Air Quality in Kenosha, Wisconsin — Live

Live readings from PurpleAir sensors across Kenosha — with free alerts when summer ozone climbs along the lakeshore.

Live Kenosha AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Kenosha and Pleasant Prairie, Somers, Racine, Twin Lakes.

Most of the year, Kenosha's air is unremarkable in the best way — a Lake Michigan breeze, no wildfire smoke season, and nothing like the wood-stove inversions that plague colder inland cities. The real story here is narrower and more specific: summer ozone, driven less by anything happening in Kenosha itself than by what blows up the shoreline from Chicago and Gary, Indiana.

Canairy watches the sensors around your home, your kids' school, and everywhere else you care about, and tells you in plain English when the air changes enough to matter.

Kenosha's ozone problem starts in Illinois, not Wisconsin

Kenosha County is officially part of the "Chicago, IL-IN-WI" ozone nonattainment area — the EPA's way of saying the summer smog here can't be managed as a Wisconsin-only problem, because the nitrogen oxides and volatile organic compounds that cook into ozone are largely produced by Chicago and Gary traffic and industry and carried north on southerly winds. Wisconsin's slice of that same nonattainment zone was reclassified from marginal to moderate on October 7, 2022, after missing its August 3, 2021 attainment deadline, then bumped again toward serious on December 17, 2024, for missing the moderate deadline of August 3, 2024 — though the Seventh Circuit stayed that move on September 5, 2025 while the state appeals. It's not the first time: under the previous federal ozone standard, this same stretch of shoreline was downgraded from moderate to serious back in 2019.

The mechanism is Lake Michigan itself. In Wisconsin's own court filings defending the state's air, regulators describe ozone here as "driven by emissions from upwind states, compounded by the meteorological effects of Lake Michigan" — a reference to the lake breeze that develops on hot, sunny days, when cooler air rolling off the water pushes inland pollution back toward the shoreline in the afternoon and effectively recirculates it instead of letting it disperse. That's why the worst ozone readings in this part of Wisconsin tend to hug the lakefront rather than spread evenly across the county.

Chiwaukee Prairie has some of the highest ozone readings in the state

Just south of the city, along the lakeshore near the Wisconsin-Illinois state line, the DNR's Chiwaukee Prairie monitor posted a 2023–2025 ozone design value of 79 parts per billion — the highest of any monitor in Wisconsin, with Racine's monitor close behind at 76 ppb. It's not a coincidence that the state's worst reading sits at the very southern tip of the Wisconsin shoreline, closest to the Chicago-Gary corridor the plume travels from.

None of this makes Kenosha a year-round pollution story. Ozone is strictly a warm-weather, sunlight-driven pollutant, so the season that matters runs roughly May through September and peaks on hot, clear, light-wind afternoons — the exact conditions that let the lake breeze recirculate exhaust instead of blowing it out. Outside those months, and even on overcast or breezy summer days, Kenosha's air is typically in the Good to Moderate range.

The county's biggest smokestack is already gone

For decades, the Pleasant Prairie Power Plant just south of the city was Wisconsin's second-largest coal-fired power station — 1,210 megawatts owned by We Energies, and a major local source of both nitrogen oxides and sulfur dioxide. We Energies retired it in April 2018, citing cheaper natural gas and renewables, which quietly removed Kenosha County's largest stationary source of ozone precursors right as the region's nonattainment fight was heating up.

That closure is part of why Kenosha's ozone problem now reads almost entirely as an imported one rather than a local-industry one: the county's own emissions have shrunk, but the summer transport from Chicago and Gary hasn't. On an ozone advisory day, the practical move is the same one anyone doing hard outdoor exercise, running, or yard work along the lakefront in Kenosha should already know — shift it earlier or later than the mid-afternoon peak, since that's when sunlight has had the most time to build ozone out of the day's traffic and industrial exhaust.

Kenosha air quality FAQ

What is the air quality in Kenosha right now?

This page shows the current AQI for Kenosha, calculated from PurpleAir sensors across the city and updated continuously. The map below shows every live sensor, so you can check the reading closest to your own neighborhood, whether that's near the lakefront or further inland.

Why does Kenosha get bad ozone in the summer?

Kenosha County is part of the federally designated Chicago, IL-IN-WI ozone nonattainment area, meaning its summer smog is treated as a shared problem with Chicago and Gary, Indiana, not a local one. Nitrogen oxides and volatile organic compounds from that corridor drift north along Lake Michigan, and a lake breeze on hot, sunny days can push that pollution back toward the shoreline instead of letting it disperse, which is why readings tend to run highest right along the lakefront on the worst afternoons, roughly May through September.

What AQI level is unhealthy?

Under the US EPA scale, AQI 0-50 is Good and 51-100 is Moderate. From 101 the air is Unhealthy for Sensitive Groups - kids, older adults, and people with asthma or heart conditions - and above 150 it's Unhealthy for everyone. Canairy translates these numbers into a plain-English verdict, like whether to close the windows or move a workout indoors.

Where does Canairy's Kenosha data come from?

Readings come from PurpleAir's network of laser particle sensors across Kenosha and surrounding towns, cross-referenced with government monitors and the Google Air Quality API. You can see every sensor behind your numbers on the live map - there's no black box.

Is Canairy free?

Yes. The Canairy app is free to download and includes live air quality for all your saved places, plain-English verdicts, and free push alerts when the air crosses your threshold. A paid plan adds extras like SMS text alerts.

Is Kenosha's air quality bad all year?

No. Ozone is a warm-weather pollutant that needs strong sunlight to form, so the season that matters runs roughly May through September and peaks on hot, clear, light-wind afternoons. Outside that window, and on breezier or overcast summer days, Kenosha's air is typically Good to Moderate - the county's largest stationary pollution source, the coal-fired Pleasant Prairie Power Plant, also shut down in 2018.

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