Air Quality in Greensboro, North Carolina — Live

Live readings from PurpleAir sensors across Greensboro — with free alerts the moment summer ozone crosses the line.

Live Greensboro AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Greensboro and High Point, Jamestown, Kernersville, Oak Ridge.

Greensboro's air is in good shape most of the year — the rolling Piedmont doesn't trap smog the way a true valley does. The exception is summer: on hot, sunny, windless days from June through September, Greensboro sits inside exactly the kind of airshed that builds ground-level ozone, and the region has spent decades under federal nonattainment and maintenance status because of it.

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.

Greensboro's real air problem is summer ozone, not smoke

Greensboro anchors one corner of the Greensboro-Winston-Salem-High Point 8-hour ozone area, a region the EPA once designated nonattainment and has since redesignated to maintenance status under the 1997 ozone standard — meaning the air met the federal bar, but regulators are still watching to make sure it stays that way. Ground-level ozone isn't smoke or soot; it forms when sunlight cooks vehicle and industrial exhaust, so the worst days show up in July and August heat, not winter.

The Forsyth County Office of Environmental Assistance and Protection forecasts ozone for the whole nine-county Triad airshed — Forsyth, Guilford, Alamance, Davidson, Randolph, Rockingham, Caswell, Davie, and Stokes — and calls a Code Orange Ozone Action Day when 90-degree heat, bright sun, and stagnant air are all lining up. Because ozone forms across that shared airshed rather than over one city alone, Greensboro, High Point, and Winston-Salem usually get the same alert on the same afternoon.

Even Greensboro got Canadian wildfire smoke in 2023

Wildfire smoke isn't the annual story here that it is in California, but it isn't unheard of either. In June 2023, smoke from Canadian wildfires burning more than a thousand miles away drifted down into central North Carolina and settled over the Triad at the same time as a summer heat-and-ozone alert — two separate problems stacking on top of each other instead of one replacing the other.

Local coverage at the time reported the Triad as the only region within hundreds of miles still under an active air-quality alert that week, even as the smoke moved on elsewhere. It was a reminder that Greensboro's air can turn for reasons that have nothing to do with anything happening in Guilford County — the sensors are what tell you it's happening, not the sky, which can look only mildly hazy while the particle count is genuinely unhealthy.

Three interstates and an airport, not a smoke-trapping valley

Greensboro sits in the rolling Piedmont at around 897 feet, drained by the Deep and Haw rivers, with no mountain ring or valley floor to hold pollution in place the way it does out West — most days, wind clears the air out completely. What the geography does concentrate is traffic: I-40, I-85, and I-73 all converge in the city, and Piedmont Triad International Airport, home to a FedEx cargo hub, adds its own steady stream of engine exhaust to the same air.

None of that shows up as visible smog most of the year. It matters on the handful of summer days when the wind dies down and the sun is strong enough to turn that exhaust into ozone faster than it can disperse — which is precisely the combination the Code Orange alerts are built to catch.

Greensboro air quality FAQ

What is the air quality in Greensboro right now?

This page shows the current AQI for Greensboro, calculated from PurpleAir sensors across the city and Guilford County and updated continuously. The map below shows every live sensor, so you can check the reading closest to your own neighborhood.

Why does Greensboro get ozone alerts in the summer?

Greensboro sits inside the Greensboro-Winston-Salem-High Point ozone maintenance area, and on hot, sunny, stagnant days — typically July and August — sunlight cooks exhaust from the region's converging interstates and airport into ground-level ozone. The Forsyth County Office of Environmental Assistance and Protection calls a Code Orange Ozone Action Day for the whole nine-county Triad airshed when that mix is expected, which is why Greensboro, High Point, and Winston-Salem often get the same alert on the same afternoon.

Does wildfire smoke ever reach Greensboro?

It can, even without a fire anywhere nearby. In June 2023, smoke from Canadian wildfires drifted all the way into central North Carolina and stacked on top of a summer heat-and-ozone alert, and the Triad was reported as the only region within hundreds of miles under an active air-quality alert that week. It isn't an annual event the way it is out West, but it shows the air here isn't only about local traffic and heat.

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 Greensboro data come from?

Readings come from PurpleAir's network of laser particle sensors across Greensboro 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.

Get Canairy free on Google Play.