Air Quality in St. George, Utah — Live
Live readings from PurpleAir sensors across St. George — with free alerts when dust or smoke moves in.
AQI 7 from 2 PurpleAir sensors · Holding steady · data from PurpleAir
As of , the air quality in St. George, Utah is AQI 7 — Good and holding steady — with PM2.5 at 1.4 µg/m³, the median of 2 live PurpleAir sensors reading 5 to 10. 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 St. George: 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 St. George and Washington, Santa Clara, Ivins, Hurricane. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in St. George
The sensors Canairy reads in St. George agree right now — all 2 sit in the Good band, a 5-point spread — so the city-wide number is a fair description of the whole area today.
| From city center | AQI | Category |
|---|---|---|
| 3.2 mi WNW | 5 | Good |
| 5.1 mi NE | 10 | Good |
St. George's air is clear most of the year — this stretch of southwestern Utah gets close to 300 sunny days, and the desert setting usually keeps things clean. The exceptions are real and specific to this valley: spring windstorms that lift dust off the surrounding desert floor and dry washes, construction dust from one of the fastest-growing metro areas in the country, and, in recent fire seasons, smoke drifting down from burns in the Pine Valley Mountains and Dixie National Forest just north of the city.
What Canairy does for St. George
A clear verdict
Not just a number — a plain-English call for St. George: 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 St. George or across the country, on one screen.
What the air in St. George is doing next
| When | Expected air quality | Main pollutant |
|---|---|---|
| Today | Good | ozone |
| Tomorrow | Good | ozone |
Forecast from EPA AirNow for the Hurricane reporting area. Canairy watches the live sensors against it and tells you when the air actually crosses your threshold, rather than leaving you to check.
Spring is blowing-dust season in St. George
St. George sits in a high desert valley where the Colorado Plateau meets the Great Basin, ringed by the Beaver Dam Mountains to the west and the Pine Valley Mountains to the north. According to the Utah Geological Survey, the state's dust storms peak from March through May, driven by cold fronts sweeping across dry lakebeds and desert basins, with a smaller second wave in the fall.
Washington County's dry wash bottoms and disturbed rangeland add to the mix, so a windy spring afternoon can push PM10 well above where it sits on a calm summer morning — with no fire anywhere nearby. It's a quieter problem than a wildfire plume, but a strong dust event can still cut visibility along I-15 and send fine particles into neighborhoods on the valley's west side.
Rapid growth has brought a stranger kind of dust problem: Valley Fever
St. George has been one of the fastest-growing metro areas in the country, and all that new construction is disturbing Mojave Desert soil that had sat undisturbed for generations. That soil can carry Coccidioides, the fungus behind Valley Fever, and a 2021 University of Utah study found the illness is more than eight times as common in southern Utah as in the rest of the state.
The problem isn't confined to St. George proper. In nearby Hurricane, residents living next to active building sites have described dust so constant that cleaning barely makes a difference. Utah epidemiologist BreAnn Osborne has said the region where the fungus can survive is expanding as the climate warms, pushing beyond the traditional St. George area — a reminder that not every local air problem here is about smoke or ozone.
Wildfire smoke reaches St. George too, even from nearby canyons
The city itself isn't surrounded by heavy timber, but the Pine Valley Mountains and Dixie National Forest, roughly 30 miles north, do burn. The Forsyth Fire started from a lightning strike in June 2025, grew past 13,600 acres in the Pine Valley area after strong winds pushed it on June 19, destroyed more than a dozen homes and outbuildings, and closed the Pine Valley Recreation Area for the rest of the season.
Utah's Division of Air Quality runs a monitoring station in Washington County tracking PM2.5, PM10, and ozone, and it flags wildfire smoke as the main seasonal risk for particle-pollution spikes. Smoke doesn't have to start close to town, either — fires burning across Arizona, Nevada, or California can drift into the valley on the wrong wind, the same as it does across the rest of the Southwest.
St. George air quality FAQ
What is the air quality in St. George right now?
As of September 15, 2026 at 6:10 AM MDT, the air quality in St. George, Utah is AQI 7 — Good — with PM2.5 at 1.4 µg/m³, the median of 2 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why does St. George get dusty in the spring?
St. George sits in a high desert valley where dry washes, disturbed rangeland, and nearby desert basins can all become dust sources. Utah's dust storms peak from March through May as cold fronts sweep through, and a windy spring afternoon can push PM10 noticeably higher than a calm summer morning, even with no fire anywhere nearby.
What is Valley Fever, and does it affect St. George's air?
Valley Fever is a fungal infection caused by inhaling spores from disturbed desert soil, and a 2021 University of Utah study found it is more than eight times as common in southern Utah as elsewhere in the state. It's tied to the region's rapid construction growth rather than smoke or ozone, which is why Canairy's particle readings are worth checking even on days that don't look hazy or smoky.
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 2 curated PurpleAir sensors Canairy tracks in and around St. George, 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 St. George
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