Air Quality in Lowell, Massachusetts — Live

Live readings from PurpleAir sensors across Lowell — with free alerts the moment the air changes enough to matter.

Live Lowell AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Lowell and Dracut, Tewksbury, Chelmsford, Billerica.

Most of Middlesex County, where Lowell sits, actually earns some of the cleanest daily particle-pollution grades in the country — the American Lung Association's 2026 State of the Air report named Middlesex among the cleanest counties nationwide on that measure. But two things complicate that clean county-wide average: Canadian wildfire smoke that has now reached Massachusetts in back-to-back summers, and a very local, very current fight over the diesel backup generators at a data center wedged between the Sacred Heart and Back Central neighborhoods.

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.

Canadian wildfire smoke keeps finding its way to the Merrimack Valley

Massachusetts has been under statewide wildfire-smoke advisories twice in recent years, and both times Lowell was inside the alert area along with the rest of the state. In June 2023, the Massachusetts Department of Environmental Protection warned that smoke drifting down from Quebec wildfires would sweep in from the west that evening and spread eastward across the entire Commonwealth overnight, turning the sky hazy and pushing fine-particle readings up statewide.

It happened again in July 2026, when smoke tracked south from wildfires burning in far northern Minnesota and Ontario. Meteorologists noted that most of that smoke layer stayed miles above the ground rather than settling at street level, but warned that shifting winds could still mix some of it down, enough to dull the sun to a reddish disc and leave a faint campfire smell in the air. That distinction — smoke aloft versus smoke on the ground — is exactly why a citywide alert on the news doesn't tell you what your own block is actually breathing, and why the sensor reading matters more than the color of the sunset.

A decade-old data center and the fight over its diesel generators

On the edge of Lowell's Sacred Heart and Back Central neighborhoods, the Markley Group runs a 352,000-square-foot data center that leans on diesel generators for backup power. In July 2025, the state approved an air-quality permit letting the company add eight more units, taking the site from 19 diesel generators to 27, along with 16 cooling towers — with one generator sitting just 84 feet from a resident's home.

Neighbors describe diesel fumes reaching second-story windows and cooling-tower mist settling on their properties, on top of the noise from running generators behind a neighborhood Little League field. Resident Jacob Fortes has called it "the nightmare situation of which I've been in for 10 years." Both neighborhoods are designated environmental justice communities under Massachusetts law, and in April 2026 ten residents, organized as Honest Future for Lowell, sued in Middlesex Superior Court arguing the state ignored its own cumulative-impact rules when it approved the expansion. By late July, with construction still underway, they asked a judge to pause it outright while the case is decided.

Why the county's good grade doesn't mean every day is clear

Middlesex County's clean-particle ranking is real, but it's a year-round average, and it says nothing about ozone, which forms fresh on hot, sunny, stagnant days regardless of county lines. The wider Boston-Worcester-Providence metro area — the group Lowell is graded alongside — still failed the American Lung Association's 2026 report for ozone smog, and it isn't hard to see why: the Lowell Connector funnels traffic from Route 3 and I-495 straight into downtown, and that corridor is exactly where summer heat, sun, and tailpipe exhaust cook into ground-level ozone.

A few miles away, the contrast is sharper still. Essex County, just across the Merrimack in Lawrence and Haverhill, earned the only F grade in the state for daily particle pollution in that same 2026 report, while Middlesex made the cleanest-counties list. That's the honest picture for Lowell: a genuinely good county-wide baseline, sitting right next to some of the state's worst air, with local sources — the highway corridor, a data center's generators — that a single average can't show you. It's why Canairy reads the sensors nearest to the places you've actually saved, not just the number for the county.

Lowell air quality FAQ

What is the air quality in Lowell right now?

This page shows the current AQI for Lowell, 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 are Lowell residents suing over a data center's diesel generators?

The Markley Group's data center on the edge of the Sacred Heart and Back Central neighborhoods runs on diesel backup generators, and the state approved a 2025 expansion that brought the site to 27 of them plus 16 cooling towers, with one generator just 84 feet from a home. In April 2026, ten residents sued in Middlesex Superior Court arguing regulators ignored the cumulative pollution burden on two neighborhoods that are both designated environmental justice communities, and by July they were asking a judge to pause construction while the case plays out.

Does Canadian wildfire smoke reach Lowell?

Yes. Massachusetts issued statewide wildfire-smoke advisories in June 2023 and again in July 2026, and both covered the entire Commonwealth, Lowell included. Not every smoke event settles at ground level — some stays miles up and only dulls the sunlight — which is exactly why checking the sensor reading tells you more than judging the sky.

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 Lowell data come from?

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