Air Quality in Great Falls, Montana — Live

Live readings from PurpleAir sensors across Great Falls — with free alerts when wildfire smoke drifts in on the wind.

Live Great Falls AQI from nearby PurpleAir sensors loads when this page opens in a browser, along with a live sensor map covering Great Falls and Black Eagle, Belt, Cascade, Vaughn.

Great Falls sits out on the open plains where the Missouri River drops over its namesake falls, with nothing like the enclosed valley that traps smoke in towns on the west side of Montana. Most days the air here is genuinely good, and wind is the reason why - Great Falls is regularly ranked among the windiest cities in the country. The exception comes when that same wind turns into a delivery system, carrying wildfire smoke in from Idaho, British Columbia, Alberta, or wherever the West's fire season happens to be burning that 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.

Great Falls' air is clean mostly because of the wind, not despite it

Sitting on the plains at about 3,333 feet with the Rocky Mountain Front rising just to the west, Great Falls has none of the bowl-shaped geography that lets smoke and haze pool over west-side Montana towns like Missoula. Instead the city is known for its wind: NOAA's 1991-2020 climate normals put its average wind speed at roughly 12.5 mph, among the highest of any US city, with gusts along the immediate Rocky Mountain Front regularly topping 70 mph. That constant movement is ordinarily a clean-air asset - pollution doesn't get the chance to sit still and build up.

The city's own history leaned on that same logic. The Anaconda copper smelter that operated in the Black Eagle neighborhood from 1890 to 1980 built a 506-foot smokestack in 1908 - the tallest chimney in the world at the time - specifically to loft its fumes high enough for the plains wind to carry them away rather than let them settle over the city. The smelter is long gone, but the same wind that once dispersed its smoke is still the biggest reason Great Falls posts far more Good and Moderate AQI days than Unhealthy ones.

The real risk is smoke blown in from somewhere else

When Great Falls does have a bad air day, it's rarely a local fire - it's smoke arriving on the wind from hundreds of miles away. In July 2021, Great Falls and Cut Bank were both listed at Unhealthy air quality as smoke from fires burning across Montana and the wider West combined. By August, Montana DEQ was advising residents to stay indoors as a northwesterly flow pushed smoke from wildfires in Idaho and British Columbia across the state, and by September 9-10 that year a stalled upper-level high had pivoted smoke and haze from southwestern Montana and Idaho fires over a 20-county stretch running from Missoula through Helena, Butte, Bozeman, and Great Falls, holding conditions at Unhealthy for days.

Canadian wildfires have become the more recent version of the same pattern. Smoke from more than a hundred fires burning across Canada spread into Montana in May 2023, and on September 3, 2025, Montana DEQ was again tracking winds funneling Canadian wildfire smoke across most of the state. The mechanism is consistent: the same northwesterly and westerly winds that usually keep Great Falls' air clean can, under the right upper-air pattern, turn into a conveyor belt for smoke that started a fire season away.

Who should watch it closest here

Malmstrom Air Force Base sits on the city's northeast edge and is home to thousands of Air Force families, many new to Montana and unfamiliar with the summer smoke pattern longtime residents have learned to watch for. Farm and ranch workers across Cascade County's wheat country - Great Falls is home to both the Montana Wheat and Barley Committee and the state's only federally licensed grain-testing lab, the Montana State Grain Laboratory - also spend full harvest days outdoors, which makes the difference between a Moderate and an Unhealthy-for-Sensitive-Groups reading more than academic.

The habit longtime locals have learned: check the number before committing to a long outdoor day, not after the horizon turns hazy. Smoke arriving from Idaho, British Columbia, or Alberta can show up as a change in the light before it shows up as a smell, and by the time Great Falls' famous wind is obviously pushing haze down the street, the air has usually already turned for the worse.

Great Falls air quality FAQ

What is the air quality in Great Falls right now?

This page shows the current AQI for Great Falls, 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 Great Falls get smoky when the fires aren't even in Montana?

Great Falls sits on open plains with none of the enclosed valleys that trap smoke in western Montana towns, so its air quality depends heavily on the wind - and that same wind can carry smoke in from hundreds of miles away. Fires in Idaho, British Columbia, and Alberta pushed Great Falls to Unhealthy AQI readings during stretches of July and September 2021, and Canada's unusually active 2023 and 2025 fire seasons both sent smoke into the city even though nothing was burning nearby.

Is Great Falls really one of the windiest cities in the US?

Yes. NOAA's 1991-2020 climate normals put Great Falls' average wind speed at roughly 12.5 mph, among the highest of any US city, with gusts along the nearby Rocky Mountain Front regularly topping 70 mph. That wind is normally good news for air quality since it keeps pollution from sitting still, but it's also the reason wildfire smoke from other states and Canada can arrive here so quickly.

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 Great Falls data come from?

Readings come from PurpleAir's network of laser particle sensors across Great Falls and surrounding Cascade County 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.