Air Quality in Atlanta, Georgia — Live

Live readings from PurpleAir sensors across Atlanta — with free alerts the moment the air turns.

Live Atlanta AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Atlanta and Decatur, Marietta, Sandy Springs, Roswell.

Atlanta's air problem is ozone, and it is a summer problem. The seven-county metro area — Bartow, Clayton, Cobb, DeKalb, Fulton, Gwinnett and Henry — spent years designated nonattainment for the federal ozone standard and was only redesignated to attainment on 17 October 2022, on the strength of certified monitoring data from 2018 to 2020. Georgia EPD credits cleaner passenger vehicles for most of that: across roughly thirty years the state cut nitrogen oxide emissions 68 percent and volatile organic compounds 57 percent while vehicle miles travelled rose 59 percent. The improvement is real and it is not finished. The worst air day in metro Atlanta in 2025 was 25 June, when the United Avenue monitor in southeast Atlanta reached AQI 129 on ozone, on a hot afternoon.

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.

The worst air comes on the hottest, stillest afternoons

Ozone is not emitted by anything. It is manufactured in the air on hot sunny days out of traffic exhaust and other pollution, which is why Atlanta's bad days cluster in June, July and August and almost never in winter. NASA's Project ATLANTA — the Atlanta Land-use Analysis: Temperature and Air-quality study, begun in 1996 and presented in March 1999 — found the metro running up to 10 degrees hotter than the rural land around it, and made the connection to air quality explicit: with a 10-degree rise in temperature, the rate of the chemical reaction that creates ozone roughly doubles. The same heat island is strong enough to trigger its own thunderstorms south of the city.

The traffic feeding that reaction is not concentrated downtown. Georgia DOT puts average daily traffic on the I-285 Westside Corridor at 194,000 vehicles, with trucks making up 18 percent of it. And the monitors that catch the highest ozone are almost all outside the Perimeter. In 2024, metro Atlanta's five worst days were every one of them ozone days, and they were recorded at Gwinnett Tech in Lawrenceville (AQI 161 on 26 June), McDonough in Henry County (133 on 14 June), Douglasville (133 on 25 June) and South DeKalb (133 on 13 July). Ozone forms downwind while the plume cooks in sunlight, so the highest number of the day is rarely at the busiest interchange.

The tree canopy cuts both ways

Atlanta has the densest urban tree coverage of any major American city, which is where the City in a Forest name comes from. That matters for air quality in a way people do not always connect: NASA's thermal imaging of Atlanta shows heavily vegetated areas as the coolest surfaces in the metro, cooled by evaporation from the leaves, while pavement and rooftops run hottest. Every degree the canopy takes off a July afternoon is a degree not going into making ozone.

The same canopy is also why spring here is what it is. On 29 March 2025 Atlanta Allergy & Asthma logged 14,801 pollen grains per cubic metre of air, the highest count in 35 years, beating the previous record of 9,369 set in 2012. On the same date a year earlier the count had been 1,646. Oak, pine, sycamore, sweetgum and birch did most of it. Worth knowing: pollen is not what an AQI number measures. A PurpleAir sensor reads fine particles, PM2.5, and a record pollen day can pass with the AQI sitting comfortably in the Good range while half the city feels terrible.

The summer the smoke actually got here

Atlanta is a long way from fire country and usually sees wildfire smoke, if at all, as high haze that never reaches the ground. 2023 was the exception. Georgia issued a Code Orange alert for the greater metro area for Friday 9 June 2023 as smoke from Canada filtered south, and the measurable hit came a few weeks later: EPA monitors recorded AQI 124 at South DeKalb on 17 July and 153 — Unhealthy, for everyone — at the McDonough monitor in Henry County on 18 July, both driven by PM2.5 rather than ozone. Georgia Tech researchers tracking the same episode measured fine particulate above 55 micrograms per cubic metre south of Atlanta on 18 and 19 July, from more than 900 fires burning in Canada.

It is worth keeping that in proportion. Across all of 2023 metro Atlanta had 3 Unhealthy days and 18 Unhealthy for Sensitive Groups days, with a peak of AQI 172. In 2025 it had no Unhealthy days at all, 6 Unhealthy for Sensitive Groups days, 150 Good days and a peak of 129. Smoke is the dramatic story; ozone is the one that shows up most years.

Atlanta air quality FAQ

Why is there smoke in Atlanta today?

Most of the time in Atlanta it is not smoke. A hazy, flat white summer sky here is usually humidity plus ozone, and ozone is invisible — you cannot see it, and it will not smell like anything. Real smoke does reach the city occasionally: in mid-July 2023 Canadian wildfire smoke pushed the McDonough monitor to AQI 153, the only Unhealthy day the metro recorded that summer that was not ozone. The way to tell them apart is the pollutant. Smoke moves PM2.5, which is exactly what the sensors on this page read, so if the PM2.5 number is climbing and the air smells like a campfire, it is smoke. If the number is normal and the sky is just milky and still, it is heat and haze.

What is the air quality in Atlanta right now?

This page shows the live AQI for Atlanta, read from PurpleAir sensors around the city and updated continuously. One number rarely covers the whole metro on an ozone day — the highest readings in 2024 came from Lawrenceville, McDonough and Douglasville rather than from inside the Perimeter — so it is worth saving the specific places you care about instead of watching a single citywide figure.

When is ozone worst in Atlanta?

Late afternoon and early evening, from roughly June through August, on days that are hot, sunny and still. The pattern is consistent in the record: metro Atlanta's worst day in 2023 was 29 June, in 2024 it was 26 June, and in 2025 it was 25 June, and all three were ozone. Cloud, wind or rain usually breaks it. If you run or ride outdoors in summer, mornings are reliably better than evenings here.

Do Atlanta's trees make the air better or worse?

Better for temperature and therefore for ozone — NASA's thermal maps of Atlanta show vegetated land as the coolest surface in the metro, and heat is what drives ozone formation. Harder in spring for anyone with allergies. Atlanta Allergy & Asthma recorded 14,801 pollen grains per cubic metre on 29 March 2025, a 35-year record, mostly oak, pine, sycamore, sweetgum and birch. Pollen does not register on an air quality index, so on a heavy pollen day the AQI on this page can read Good while your eyes disagree.

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.

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.

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