Air Quality in Winston-Salem, North Carolina — Live

Live readings from PurpleAir sensors across Winston-Salem — with free alerts the moment ozone or particle pollution climbs.

Live Winston-Salem AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Winston-Salem and Kernersville, Clemmons, Lewisville, Rural Hall.

Winston-Salem's air is unremarkable for most of the year — this is Piedmont North Carolina, not a smoke-prone canyon or a coastal refinery town. The real pattern shows up in summer, when the Piedmont Triad's own environmental office declares Code Orange ozone action days on the hottest, stillest afternoons, covering Forsyth County and eight neighboring counties at once.

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.

Why Winston-Salem gets Code Orange days in summer

The Forsyth County Office of Environmental Assistance and Protection issued a Code Orange ozone action day on May 20, 2026, warning of high temperatures in the 90s, bright sunlight, low humidity, and a stagnant air mass — the exact recipe that cooks vehicle and industrial exhaust into ground-level ozone. It happened again on July 16, 2026, this time described as unhealthy for sensitive groups under a similar mix of heat, sun, and stalled air. Both alerts covered all nine Triad counties at once — Forsyth, Guilford, Alamance, Davidson, Randolph, Rockingham, Caswell, Davie, and Stokes — because ozone forms regionally and does not respect county lines.

On these days, officials ask that people who are older, are children, or have heart or lung disease limit prolonged outdoor exertion and take frequent breaks. Everyone else gets asked to help by driving less, skipping the gas-powered lawn mower, and holding off on open burning until the alert lifts, because it is mostly cars, mowers, and stationary sources that supply the raw ingredients ozone needs to form on a hot, sunny, windless afternoon.

Forsyth County's ozone problem is not new

The EPA first designated Forsyth County a moderate nonattainment area for ozone back in November 1991, grouped with Guilford and Davidson counties and part of Davie County. County records describe the years that followed as rough: by the late 1990s the Triad was racking up 30 to 35 exceedances of the ozone standard in a single ozone season. Cleaner vehicle engines, tighter industrial permits, and stricter fuel rules turned that around, and the numbers started dropping around 2004 and 2005.

The improvement was real, but it was not a finish line. The American Lung Association's 2026 State of the Air report, built on 2022-2024 monitoring data, still gives the Greensboro-Winston-Salem-High Point metro a C for ozone, ranking it 100th worst nationally, and a D for short-term particle pollution, ranking 76th worst. Winston-Salem sits inland on the Piedmont plateau with no mountains or valley walls to trap anything; the air here turns bad because of heat and stillness, not because the terrain bottles it up.

US 52 and Business 40 run pollution straight through downtown

Winston-Salem's core sits at the crossing of US 52 and Business 40, the urban freeway link that ties I-77, I-40, and I-85 together through the middle of the city. Traffic on that corridor is a steady year-round source of the nitrogen oxides and fine particles that add to the ozone mix on summer afternoons and to the particle-pollution numbers the rest of the year. The city's tobacco and textile manufacturing history — R.J. Reynolds and Hanes both trace their roots here — has faded as a smokestack source, but the highway network that grew up to move goods and workers around those old plants never went away.

That combination is why a single number for the whole city can be misleading. A reading taken a few blocks from the US 52 or I-40 interchange downtown can run noticeably higher than one out in Clemmons or Lewisville on the same afternoon. Checking the sensor near the place you actually are, not just the citywide average, is the difference between an accurate call and a guess.

Winston-Salem air quality FAQ

What is the air quality in Winston-Salem right now?

This page shows the current AQI for Winston-Salem, 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.

Why does Winston-Salem get ozone action days in summer?

Hot, sunny, windless afternoons let vehicle exhaust and other emissions cook into ground-level ozone faster than it can disperse. The Forsyth County Office of Environmental Assistance and Protection declared Code Orange ozone action days on May 20 and July 16, 2026, both driven by 90-degree heat, strong sun, and a stagnant air mass across the nine-county Piedmont Triad region.

Has Winston-Salem's air quality always been this way?

It has actually improved. The EPA designated Forsyth County a nonattainment area for ozone in 1991, and by the late 1990s the Triad was seeing 30 to 35 days a year over the ozone standard. Cleaner engines and tighter industrial rules brought that down starting around 2004, though the region still earns a C for ozone and a D for particle pollution in the American Lung Association's 2026 report.

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 Winston-Salem data come from?

Readings come from PurpleAir's network of laser particle sensors across Winston-Salem 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 is 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.