Air Quality in Huntsville, Alabama — Live
Live readings from PurpleAir sensors across Huntsville — with free alerts when summer ozone or a smoke day pushes the air past healthy.
AQI 54 from 4 PurpleAir sensors · Trending down · data from PurpleAir
As of , the air quality in Huntsville, Alabama is AQI 54 — Moderate and falling — with PM2.5 at 10.9 µg/m³, the median of 4 live PurpleAir sensors reading 50 to 58. Canairy's verdict: Mostly clear.
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 Huntsville: weeds pollen is the strongest of the three at a high 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 Huntsville and Madison, Decatur, Athens, Owens Cross Roads. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Huntsville
The sensors Canairy reads in Huntsville are 8 AQI points apart right now, from Good to Moderate, which is the whole reason one city-wide number can mislead you: the median describes air you may not be standing in.
| From city center | AQI | Category |
|---|---|---|
| 0.4 mi SSW | 58 | Moderate |
| 5.6 mi W | 50 | Good |
| 10.1 mi ESE | 54 | Moderate |
| 10.4 mi NNW | 54 | Moderate |
Madison County is one of Alabama's official air quality success stories — the EPA lists it as in attainment for every pollutant it regulates, and most days the AQI here sits comfortably in the Good range. The exceptions are narrow and fairly predictable: a run of hot, hazy, storm-free days in July and August when ozone builds up faster than the valley can clear it, and the rare summer when smoke drifts in from somewhere else entirely, like the Canadian wildfires that triggered air quality alerts here in June and July 2023.
What Canairy does for Huntsville
A clear verdict
Not just a number — a plain-English call for Huntsville: 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 Huntsville or across the country, on one screen.
Huntsville sits in a bowl of low mountains
The city sits at about 640 feet in the Tennessee Valley, but it isn't open flatland — the National Weather Service describes Huntsville as "almost surrounded by the foothills of the Appalachian Mountains," with ridges running 1,200 to 1,600 feet high roughly 14 miles to the northeast, east, and southeast. Monte Sano Mountain, at 1,621 feet, rises directly on the city's east side and draws hikers precisely for the view back down into the valley.
That ring of terrain is scenic, but it also limits how fast the air over Huntsville turns over. The Tennessee River runs about seven miles south of downtown, and the valley opening to the west stays relatively flat, so on calm days the exchange of air happens mostly along that western corridor rather than straight up and out. It isn't a Los Angeles-style basin, but it's enough shelter that pollution built up locally doesn't always clear on its own.
Summer heat and humidity are what actually move the needle
Huntsville's ozone problem, such as it is, is a summer one. July and August highs regularly reach the low 90s, and the area's humid subtropical climate pushes heat index values past 100 degrees on many afternoons. That combination of heat, sunlight, and vehicle exhaust from commuters funneling into Redstone Arsenal and Cummings Research Park along Research Park Boulevard and I-565 is the recipe ground-level ozone needs. Afternoon thunderstorms interrupt the pattern on roughly a third of summer days, which is part of why Madison County has stayed within EPA ozone limits even when the numbers have run close.
The margin hasn't always been comfortable. Under the older 8-hour ozone standard, the Huntsville area's design value in the late 1990s measured 84 parts per billion — close enough to the federal line that ADEM prepared a possible nonattainment recommendation for the area in 2009. Madison County was never formally designated nonattainment and remains in attainment today, but it's a reminder that Huntsville's good air is a function of favorable weather and traffic patterns holding, not a guarantee written in stone.
The one real exception: smoke that wasn't from here at all
In June 2023, smoke from wildfires burning more than a thousand miles away in Quebec drifted far enough south to put Madison and Morgan counties under an air quality alert that ran until 9 p.m. on June 9. It came back the following month — in July 2023, ADEM issued another alert for Madison County as a second round of Canadian wildfire smoke pushed local AQI into Unhealthy for Sensitive Groups territory, prompting the Alabama Department of Public Health to advise people with asthma or COPD to keep an eye on conditions.
Neither event came close to what cities in the Northeast saw that summer — Huntsville isn't wildfire country, and there's no local fire season to plan around the way there is out West. But 2023 was a useful reminder that smoke doesn't need to start nearby to affect the air you're breathing, and that the AQI on a given July afternoon can be driven by something burning a thousand miles north rather than anything happening in Madison County.
Huntsville air quality FAQ
What is the air quality in Huntsville right now?
As of September 14, 2026 at 3:34 PM EDT, the air quality in Huntsville, Alabama is AQI 54 — Moderate — with PM2.5 at 10.9 µg/m³, the median of 4 live PurpleAir sensors. Sensitive groups may want to take it slower outside.
Why did Huntsville have air quality alerts in 2023?
Smoke from wildfires burning in Quebec drifted into north Alabama twice that year, triggering ADEM air quality alerts for Madison County in June and July 2023 that pushed AQI into Unhealthy for Sensitive Groups territory. It was an unusual event for a region that doesn't have its own wildfire season — the smoke came from more than a thousand miles away.
Why does Huntsville's air get worse in summer?
Ozone, not smoke, is Huntsville's main summer concern. Hot, humid days with highs in the low 90s and heat index values over 100 degrees, combined with exhaust from commuters heading to Redstone Arsenal and Cummings Research Park, create the conditions ground-level ozone needs. Afternoon thunderstorms usually break the pattern before it gets serious, which is part of why Madison County has stayed in attainment for ozone even though its design values have run close to the federal limit in the past.
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 4 curated PurpleAir sensors Canairy tracks in and around Huntsville, 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 Huntsville
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