Air Quality in Durham, North Carolina — Live
Live readings from PurpleAir sensors across Durham — with free alerts the moment summer ozone or drifting wildfire smoke pushes the air past healthy.
AQI 57 from 5 PurpleAir sensors · Holding steady · data from PurpleAir
As of , the air quality in Durham, North Carolina is AQI 57 — Moderate and holding steady — with PM2.5 at 12.1 µg/m³, the median of 5 live PurpleAir sensors reading 55 to 58. Canairy's verdict: Mostly clear.
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 Durham: weeds 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 Durham and Chapel Hill, Carrboro, Hillsborough, Cary. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Durham
The sensors Canairy reads in Durham agree right now — all 5 sit in the Moderate band, a 3-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 0.9 mi NNW | 57 | Moderate |
| 2.2 mi NW | 58 | Moderate |
| 4.9 mi NE | 57 | Moderate |
| 5.0 mi NNE | 56 | Moderate |
| 5.3 mi WNW | 55 | Moderate |
Durham's air is good most of the year, and it isn't a wildfire town — there's no local fire season here the way there is out West. The real story on a Durham forecast is ground-level ozone: hot, humid, stagnant Piedmont afternoons that turn traffic and industrial emissions into a Code Orange Air Quality Action Day, called jointly by the National Weather Service and NC DEQ for the Triangle and Triad.
What Canairy does for Durham
A clear verdict
Not just a number — a plain-English call for Durham: open the windows, or keep them shut.
Smoke alerts
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
Home, work, the kids' school — across Durham or across the country, on one screen.
Durham's real air problem is summer ozone, not smoke
Raleigh-Durham-Chapel Hill was one of the North Carolina metro areas designated nonattainment for ground-level ozone after the 1990 Clean Air Act Amendments, alongside Charlotte-Gastonia and Greensboro-Winston-Salem-High Point. The state didn't get the Triangle redesignated to attainment for the 8-hour ozone standard until 2007, when North Carolina's request — submitted that June — was approved by the EPA.
Exiting nonattainment on paper didn't change the weather that causes the problem. Hot, sunny, low-wind days still cook vehicle and industrial NOx into ozone across the Piedmont, and NC DEQ and the National Weather Service still call a Code Orange Air Quality Action Day for the Triangle and Triad when the forecast calls for it — usually several times a summer, with advice to cut back on prolonged outdoor exertion if you're in a sensitive group.
When Canadian wildfire smoke does reach Durham
It isn't only home-grown ozone. In the summer of 2023, smoke from Canadian wildfires drifted far enough south to push a Code Orange Air Quality Alert across central North Carolina, Durham included — thousands of miles from the fires themselves. Local coverage at the time described the smoke as continuing to affect the region's air quality into late July.
That kind of event is still the exception here, not the rule, and it doesn't follow a predictable calendar the way ozone season does. But it's now a real enough occurrence that a clear, haze-free sky in Durham isn't automatic proof the air is clean — fine smoke particles can be present well before or after anything is visible.
A flat Piedmont city with an industrial past, now built around highways and RTP
Durham sits in the Piedmont at roughly 400 feet, mostly flat with some rolling hills, which means it doesn't get the trapped winter inversions that pool smoke and cold air in mountain valleys. Its pollution history is more industrial: tobacco warehouses and mills downtown, and Duke University's own coal-fired West Campus steam plant, which the university converted to gas as part of a 2007 pledge to reach carbon neutrality by 2024.
Today the more relevant local sources are the highway corridors — I-40, I-85, and the NC 147 freeway — that carry commuter and freight traffic through and around Research Triangle Park. That traffic is exactly the NOx source that turns into ozone on the hot, still afternoons described above, which is why Durham's air quality story runs through its roads as much as its weather.
Durham air quality FAQ
What is the air quality in Durham right now?
As of September 14, 2026 at 11:38 AM EDT, the air quality in Durham, North Carolina is AQI 57 — Moderate — with PM2.5 at 12.1 µg/m³, the median of 5 live PurpleAir sensors. Sensitive groups may want to take it slower outside.
Why does Durham get ozone action days in summer?
Hot, humid, sunny afternoons with little wind let vehicle and industrial emissions cook into ground-level ozone across the Piedmont. The National Weather Service and NC DEQ call a Code Orange Air Quality Action Day for the Triangle and Triad when that's forecast, usually asking sensitive groups to skip prolonged outdoor exertion that afternoon.
Does wildfire smoke ever reach Durham?
Yes, occasionally. Smoke from Canadian wildfires drifted into central North Carolina in the summer of 2023, pushing a Code Orange Air Quality Alert across Durham and the rest of the Triangle even though the fires themselves were thousands of miles away. It isn't a yearly certainty the way it is on the West Coast, but it's no longer rare either.
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 Durham, 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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Air quality near Durham
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