Air Quality in Lowell, Massachusetts — Live
Live readings from PurpleAir sensors across Lowell — with free alerts the moment the air changes enough to matter.
AQI 46 from 3 PurpleAir sensors · Trending down · data from PurpleAir
As of , the air quality in Lowell, Massachusetts is AQI 46 — Good and falling — with PM2.5 at 8.3 µg/m³, the median of 3 live PurpleAir sensors reading 7 to 48. Canairy's verdict: Breathe easy.
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 Lowell: weeds pollen is the strongest of the three at a low 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 Lowell and Dracut, Tewksbury, Chelmsford, Billerica. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Lowell
The sensors Canairy reads in Lowell agree right now — all 3 sit in the Good band, a 41-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 0.9 mi SE | 44 | Good |
| 1.9 mi SSE | 48 | Good |
| 6.6 mi NE | 7 | Good |
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.
What Canairy does for Lowell
A clear verdict
Not just a number — a plain-English call for Lowell: 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 Lowell or across the country, on one screen.
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?
As of September 14, 2026 at 8:10 AM EDT, the air quality in Lowell, Massachusetts is AQI 46 — Good — with PM2.5 at 8.3 µg/m³, the median of 3 live PurpleAir sensors. Open the windows. Great for outdoor activity.
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 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 3 curated PurpleAir sensors Canairy tracks in and around Lowell, 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 Lowell
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