Air Quality in Kansas City, Missouri — Live
Live readings from PurpleAir sensors across Kansas City — with free alerts the moment the air turns.
AQI 28 from 5 PurpleAir sensors · Trending down · data from PurpleAir
As of , the air quality in Kansas City, Missouri is AQI 28 — Good and falling — with PM2.5 at 5.2 µg/m³, the median of 5 live PurpleAir sensors reading 21 to 47. Canairy's verdict: Breathe easy.
For scale, that PM2.5 reading is below the World Health Organization's 24-hour guideline of 15 µg/m³. The WHO figure is a daily average and this is a live reading, so read it as a sense of magnitude rather than a formal exceedance — a brief spike and a bad day are not the same thing. More on the WHO guidelines
Pollen today in Kansas City: grass pollen is the strongest of the three at a high level, from Google's pollen forecast. Canairy shows the tree, grass and weed forecast beside the air reading on every plan, including the free one.
Free to download · Live data from PurpleAir & public monitors
Live PurpleAir sensor map for Kansas City and Overland Park, Independence, Lee's Summit, Liberty. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Kansas City
The sensors Canairy reads in Kansas City agree right now — all 5 sit in the Good band, a 26-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 2.0 mi SE | 47 | Good |
| 3.4 mi S | 21 | Good |
| 6.3 mi WSW | 30 | Good |
| 6.6 mi SSW | 27 | Good |
| 7.5 mi W | 33 | Good |
Kansas City's air is fine on most days and marginal on a handful, and the handful is what the region argues about. The EPA does not list Kansas City as a nonattainment area for ozone; it is a maintenance area, covering Wyandotte and Johnson counties in Kansas and Clay, Platte and Jackson counties in Missouri, which means the metro fixed an old ozone problem and now has to keep proving it stayed fixed. The 2024 season ran 172 green days, 67 yellow, six orange and no red. The 2025 season had six days over the standard, one of them red in mid-July. That is a region living within a few parts per billion of the federal line, year after year. The other thing that moves the number here arrives from a thousand miles away: on the morning of 7 September 2023 the AQI in Kansas City hit 159, a red day, on smoke from wildfires in western Canada, and was still at 112 the next morning.
What Canairy does for Kansas City
A clear verdict
Not just a number — a plain-English call for Kansas City: open the windows, or keep them shut.
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A push or text the moment the air crosses your threshold — and again when it clears.
A heads-up before it's bad
Trend alerts catch the air turning, so you can close up the house before the smoke settles in.
Every place you care about
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The ozone number that decides Kansas City is decided by one monitor at a time
Compliance with the eight-hour ozone standard does not work the way most people assume. The standard is 70 parts per billion, but a single hot afternoon over that does not put the region in violation. What counts is the design value: the three-year average of the fourth-highest reading at each individual monitor. Any one monitor hitting 71 ppb on that average puts the whole metro in violation. Ozone here is measured at six monitors inside the maintenance area, with two more at Trimble and Leavenworth used for forecasting. In 2024 the Liberty monitor had four daily readings above the standard and reached its critical value, making it the one monitor in tentative violation, with a fourth-highest reading of 76 ppb; Heritage Park and Richards Gebaur both came in at 77 and Leavenworth at 78. In 2025 it was Rocky Creek's turn, with two other monitors landing right at 70.
That matters for how you read a citywide figure. The monitors that tip over are not downtown ones. Liberty, Watkins Mill and the sites out toward the northern edge of the metro sit downwind of the built-up core on a typical summer afternoon, and ozone is a pollutant that forms in the air over several hours as nitrogen oxides and volatile organic compounds cook in sunlight, so it tends to peak somewhere other than where it started. A number averaged across Kansas City can be genuinely comfortable on an afternoon when the air where you actually live is not.
The worst air Kansas City has had recently came from Canada
The summer of 2023 is the reference point. Smoke from Canadian wildfires, with more than 19 million acres burned nationally by late June, reached the Midwest repeatedly. On 28 June 2023 Kansas City was under an alert for air unhealthy for sensitive groups while the haze sat over the city. The sharper episode came in September: AQI 159 on the Thursday morning, 112 on the Friday, driven by particle pollution rather than ozone. MARC's own 2025 season recap describes 2023 as the year the region was badly impacted by Canadian wildfires and smoke that swept through in June and July.
2025 was a quieter year for smoke here, and the reason given was simply weather. Doug Norsby, MARC's air quality senior planner, put the 2025 season down to timely weather systems and wind that generally kept pollution moving out of the area, particularly in July. That is the honest shape of the smoke risk in Kansas City. There is no local fire season to speak of. What arrives is somebody else's fire, carried a long distance, and whether it settles on your street for an afternoon or blows through in an hour is a question about that day's wind rather than about the fire.
Where the pollution comes from in a river-bottom freight town
Kansas City sits on the Missouri River at its confluence with the Kansas River, at about 909 feet of elevation, which means a lot of the metro is bottom land with bluffs above it. Missouri's Department of Natural Resources lists the common sources of the ozone precursors as vehicles, power plants, industry, burning and biogenic emissions, and runs its ozone forecast season from 1 March through 31 October. Kansas City has more of the vehicle side than a metro its size would normally carry, because four Class I railroads have line-haul access here: Union Pacific, BNSF, Norfolk Southern and CPKC. Freight moving through a city is diesel traffic on both rails and roads, and diesel traffic is one of the nitrogen oxide sources that feeds the afternoon ozone reaction.
None of that produces a dramatic local pollution event, and it would be dishonest to suggest otherwise. What it produces is a region that hovers a couple of parts per billion either side of the standard and gets tipped over by a hot, still week. The useful thing on a page like this is not the metro headline; it is what the sensors nearest to the places you spend time are reading this afternoon.
Kansas City air quality FAQ
What is the air quality in Kansas City right now?
As of September 10, 2026 at 7:09 AM CDT, the air quality in Kansas City, Missouri is AQI 28 — Good — with PM2.5 at 5.2 µg/m³, the median of 5 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why is there smoke in Kansas City today?
Almost always because a wildfire somewhere else is sending it here. Kansas City has no local fire season, but Canadian smoke has reached the metro repeatedly since 2023, when the AQI hit 159 on the morning of 7 September and was still at 112 the following day. Smoke you can smell, and it shows up on this page as a rise in PM2.5. If the sky is hazy but there is no smell, and it is a hot still afternoon between March and October, the more likely explanation is ozone, which is invisible and does not register on a particle sensor at all.
Why does the alert say ozone when I cannot see anything?
Because ozone is a gas, not a particle. It forms when nitrogen oxides and volatile organic compounds react in sunlight, which is why the alerts cluster on hot, sunny, low-wind days between March and October, and why they are usually issued the afternoon before rather than in response to something visible. It is also why a PM2.5 sensor cannot see it. On an ozone alert day the useful response is about exertion and timing rather than about closing windows, because ozone peaks in the afternoon and eases after sunset.
Is Kansas City's air getting better or worse?
Better over the long run, and roughly flat lately. The regional ozone trend came down after 2014 as power plant controls and cleaner vehicle engines took effect, and since then the metro has sat close to or just below the standard rather than clearly under it. The 2024 season produced six days over the standard and the 2025 season also produced six, with one monitor in tentative violation each year. Kansas City is not a city with an air quality crisis. It is a city where a handful of days each summer are genuinely worth planning around.
What the AQI numbers mean
| AQI | Category | What it means for you |
|---|---|---|
| 0–50 | Good | Open the windows. Great for outdoor activity. |
| 51–100 | Moderate | Sensitive groups may want to take it slower outside. |
| 101–150 | Unhealthy for Sensitive Groups | Kids, elderly, and respiratory conditions stay closer to home. |
| 151–200 | Unhealthy | Skip outdoor exercise. Close windows. |
| 201–300 | Very Unhealthy | Limit time outside. N95 if you must go. |
| 301+ | Hazardous | Health emergency. Stay inside, run filtration if you have it. |
Canairy lets you tighten these bands if you’re more sensitive than the EPA default, so an alert can fire before the official category changes. How to read the Air Quality Index
Where these readings come from
The AQI at the top of this page is the median of the 5 curated PurpleAir sensors Canairy tracks in and around Kansas City, with outliers set aside so that one sensor brought indoors — or parked beside a barbecue — cannot set the number for a whole city. Every sensor behind it is listed above with its distance and bearing from the city center. There is no black box here.
In the app, a place you save resolves the same way first. When no neighborhood sensor is reporting it falls back to the nearest EPA AirNow monitor, and anything modeled rather than measured is labelled a regional estimate rather than passed off as a sensor reading. How low-cost sensors compare to regulatory monitors
About Canairy
Canairy is free to download. The free plan covers one saved place with live readings, a plain-English verdict, and push alerts when the air crosses a threshold you choose. Paid plans add more places, faster refreshes, and SMS alerts. It is built by two parents in Sonoma County, California, who got tired of guessing whether it was safe to send the kids outside. Why we built it
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