Air Quality in Lewiston, Maine — Live

Live readings from PurpleAir sensors across Lewiston-Auburn — with plain-English alerts for hazy summer ozone days and still winter wood-smoke nights.

Live Lewiston AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Lewiston and Auburn, Sabattus, Lisbon, Greene.

Most days, the air in Lewiston and Auburn is unremarkable in the best way — this stretch of the Androscoggin River valley doesn't have a wildfire season the way the West does. What it does have is two quieter, recurring problems: hot, hazy summer days when regional ozone builds up enough that the twin cities once carried their own federal nonattainment designation, and cold winter nights when wood-stove smoke settles into the valley instead of blowing away.

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.

Lewiston-Auburn once had its own ozone problem

From the early 1990s until the old federal ozone standard was revoked in 2005, the EPA classified Lewiston-Auburn as its own Moderate nonattainment area for ground-level ozone, covering all of Androscoggin and Kennebec counties — not folded into Portland's or Boston's designation, but named on its own. That happened because ozone doesn't need a local smokestack to form; it cooks up from vehicle exhaust and industrial emissions on hot, sunny, stagnant days, and inland Maine sits downwind of pollution carried up the whole Northeast corridor.

The standard that triggered that designation is gone, replaced by tighter modern rules, but the weather pattern that caused it hasn't changed. A hot, humid, windless day in July or August is still when Lewiston-Auburn's air is most likely to slide into the Moderate or Unhealthy for Sensitive Groups range — the kind of day that looks perfectly clear but is genuinely harder on a kid with asthma or someone doing yard work all afternoon.

Winter is when the wood smoke settles in

Maine relies on wood heat more than almost any state in the country. Census Bureau survey data puts roughly 8 percent of Maine households on wood as their primary heat source — second only to Vermont nationally. Lewiston and Auburn sit low in a river valley, and on the cold, calm nights that are common in a Maine winter, smoke from wood stoves and fireplaces has nowhere to go. It settles at ground level instead of dispersing the way it would on a windy day.

That's a different kind of pollution problem than the summer ozone story: it's fine particulate matter (PM2.5) instead of ozone, it shows up overnight and in the early morning instead of in the afternoon, and it's hyper-local — one street burning wood on a still night can be measurably worse than another a mile away. That's exactly the kind of gap a single official monitor for the whole metro area will miss, and a network of neighborhood sensors is built to close.

What actually changes on a bad-air day here

There's no dramatic sky-turns-orange moment in Lewiston-Auburn the way there is in a wildfire-prone city — the numbers move, but the sky usually still looks normal. That's exactly why a plain number matters more here, not less: on a hazy July afternoon or a still January night, the AQI can climb into a range worth changing your afternoon around even though nothing looks wrong outside.

If you or your kids deal with asthma, checking before an afternoon outdoors on a hot, still summer day is worth the ten seconds it takes. In winter the same logic applies to a still, cold evening — if your neighborhood is thick with wood smoke, cracking a window for fresh air can do the opposite of what you intend. Canairy is built to catch both kinds of days, not just the wildfire-smoke story that dominates most air-quality apps.

Lewiston air quality FAQ

What is the air quality in Lewiston right now?

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

Why did Lewiston-Auburn have its own ozone problem?

From the early 1990s until the federal standard was revoked in 2005, the EPA classified Lewiston-Auburn as its own Moderate nonattainment area for ground-level ozone, covering all of Androscoggin and Kennebec counties. Ozone builds up on hot, sunny, stagnant days from vehicle and industrial emissions carried in on regional winds, and that same weather pattern still produces the metro's worst summer air days even though the old designation is gone.

Does Lewiston get smoky in winter from wood stoves?

It can. Maine has one of the highest rates of wood heating in the country — around 8 percent of households burn wood as their primary heat source, second only to Vermont — and on cold, calm nights common to a Maine winter, that smoke settles into the Androscoggin River valley instead of blowing through. It's a quieter, more local problem than summer ozone, and it tends to show up overnight and in the early morning.

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 Lewiston data come from?

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