Air Quality in Billings, Montana — Live

Live readings from PurpleAir sensors across Billings — with free alerts when refinery smog, winter inversions, or wildfire smoke move in.

Live Billings AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Billings and Laurel, Lockwood, Shepherd, Huntley.

Billings sits in the Yellowstone River valley, boxed in by the sandstone Rimrocks to the north and east, and most of the year the air here is unremarkable in the best sense. What sets it apart from a typical Montana town is industry: Billings and neighboring Laurel host three of Montana's four oil refineries, and the area has spent decades under a federal cleanup plan for sulfur dioxide. Add in winter nights when the valley traps cold, still air under a temperature inversion, plus a few weeks most summers when wildfire smoke - Montana's own or drifted down from Canada - fills the valley, and an otherwise mild climate gets a handful of genuinely bad-air stretches every year.

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.

The Rimrocks box the valley in

Billings sits around 3,100 to 3,200 feet above sea level in the Yellowstone River valley, hemmed in by the Rimrocks - sandstone cliffs that rise roughly 500 feet along downtown's north edge and as much as 800 feet near the airport to the east. That terrain does more than separate downtown from the Heights and Lockwood; on calm, clear winter nights it helps trap a shallow layer of cold, dense air right at the valley floor while warmer air sits above it, a classic temperature inversion.

When that sets up, whatever is in the air - vehicle exhaust, wood smoke, refinery emissions - has nowhere to vent, and PM2.5 can build for days until a Chinook wind or a passing storm finally scours the valley out. It's the same basic mechanism that gives a lot of Rocky Mountain valley towns their worst air days, just with an unusually specific added ingredient in Billings' case: heavy industry sitting inside the same bowl.

Billings and Laurel share a federal cleanup plan for refinery pollution

Yellowstone County is home to three of Montana's four oil refineries - the Phillips 66 refinery in Billings, the CHS Inc. refinery in Laurel, and the Par Montana refinery (formerly ExxonMobil) just east of the city in Lockwood. Sulfur dioxide from these plants got the Billings/Laurel area designated nonattainment under the Clean Air Act back in 1978, and the EPA still runs a Federal Implementation Plan covering four major sources in the two towns to keep SO2 in check - the agency finalized the latest round of revisions to that plan in January 2025.

In practice, that means Billings' air story isn't only about wildfire smoke the way it is in a lot of Western cities - there's an industrial fingerprint too, most noticeable on still days when a refinery flare or upset condition can push SO2 or particulates up over one part of the valley rather than the city as a whole. It's also why a single official monitor a few miles from a refinery tells you less than a dense set of sensors that includes readings closer to Laurel and Lockwood, not just downtown.

Wildfire smoke still finds the valley most summers

Montana's own wildfire season and drifting Canadian smoke both find their way into the Yellowstone Valley. In early September 2023, smoke pushed south from wildfires burning across Canada and degraded air quality across most of Montana, Yellowstone County included, prompting a statewide air quality alert that lasted for days.

Billings also sits close enough to central and western Montana's fire country that a bad fire season anywhere in the state can put a haze over the city, even when nothing is burning nearby. Ground-level ozone, by contrast, is a minor factor here compared to particulate pollution - Billings gets plenty of summer heat, but it's the combination of smoke, refinery emissions, and winter inversions, not photochemical smog, that drives the valley's worst air-quality days.

Billings air quality FAQ

What is the air quality in Billings right now?

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

Why does Billings get winter temperature inversions?

Billings sits in the Yellowstone River valley, boxed in by the Rimrocks - sandstone cliffs that rise 500 to 800 feet along downtown's north and east edges. On calm, clear winter nights, cold air pools at the valley floor while warmer air sits above it, trapping vehicle exhaust, wood smoke, and other pollutants close to the ground until a Chinook wind or a storm system clears it out.

Does refinery pollution affect Billings' air quality?

Yes. Yellowstone County has three of Montana's four oil refineries - in Billings, Laurel, and Lockwood - and the area has operated under a federal Clean Air Act plan for sulfur dioxide since the Billings/Laurel area was designated nonattainment in 1978, with the EPA finalizing the latest update to that plan in January 2025. Canairy's sensor network lets you check readings near Laurel and Lockwood specifically, not just downtown Billings.

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 Billings data come from?

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