Air Quality in Bellevue, Washington — Live
Live readings from PurpleAir sensors across Bellevue — with free alerts the moment smoke reaches the Eastside.
AQI 31 from 4 PurpleAir sensors · Trending down · data from PurpleAir
As of , the air quality in Bellevue, Washington is AQI 31 — Good and falling — with PM2.5 at 5.6 µg/m³, the median of 4 live PurpleAir sensors reading 28 to 33. 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 Bellevue: 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 Bellevue and Kirkland, Redmond, Mercer Island, Issaquah. Every dot is a real sensor, color-coded by current air quality.
Sensor by sensor in Bellevue
The sensors Canairy reads in Bellevue agree right now — all 4 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 |
|---|---|---|
| 2.8 mi SW | 32 | Good |
| 3.7 mi ENE | 30 | Good |
| 5.9 mi NW | 28 | Good |
| 5.9 mi NW | 33 | Good |
Bellevue sits between Lake Washington and Lake Sammamish on the Eastside, and its air is good most of the year. The Puget Sound Clean Air Agency reports that the four-county region continues to meet the federal health standards for all six criteria pollutants, and it holds itself to a stricter daily fine-particle goal than the federal one. The communities carrying the region's worst wood smoke are South End Tacoma, Marysville and Darrington — not Bellevue. What does reach Bellevue is smoke from somewhere else: the Cascades in late summer and early fall, and British Columbia when the wind turns northeasterly. When it settles into the Puget Sound lowlands it does not sort itself neatly by city.
What Canairy does for Bellevue
A clear verdict
Not just a number — a plain-English call for Bellevue: 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 Bellevue or across the country, on one screen.
October 2022, when the Eastside took the worst of it
That autumn the Bolt Creek Fire near Skykomish burned more than 14,000 acres and the Loch Katrine Fire, about thirty miles east of Seattle, added another 1,200. Seattle had gone without significant rain since June 9 in what was its driest summer on record, and it was the first year a major smoke event over densely populated western Washington ever stretched into October.
On October 18 and 19 Seattle held the worst air quality of any major city in the world on IQAir's ranking, two days running. Local reporting during that stretch noted some of the worst readings were on the Eastside — people were standing in Bellevue Downtown Park unable to see the lake. It is the clearest case on record that being east of Lake Washington is not protection.
September 2020 remains the worst on Washington's record
The Labor Day fires produced smoke across the whole state. Air quality in the Puget Sound region fell to unhealthy on September 8, and between September 12 and 17 every single air quality monitor in Washington recorded fine particle pollution above the federal 24-hour standard.
Ecology described it as the most days that statewide monitoring sites had recorded hazardous air going back to 2000, with the majority of the state seeing at least five consecutive days of very unhealthy or hazardous conditions. Rain on the 17th began to clear it and the event ended around the 21st. Nothing since has approached it.
Winter here is quieter than people expect
Bellevue's winter risk is inversions rather than any large local source. When winds go calm in the colder months, a temperature inversion traps air near the ground and wood stoves and fireplaces build up beneath it — which is why the regional agency has authority to declare mandatory burn bans across King, Kitsap, Pierce and Snohomish counties.
In practice Bellevue is not where that bites hardest, and this past winter — the eighth warmest on record — stayed below burn ban thresholds entirely, with none issued. The agency has scrapped over 570 old wood stoves across the four counties since March 2025, and more than 90 percent of the four-county population now lives within five kilometres of a fine particle sensor.
Bellevue air quality FAQ
What is the air quality in Bellevue right now?
As of September 10, 2026 at 5:09 AM PDT, the air quality in Bellevue, Washington is AQI 31 — Good — with PM2.5 at 5.6 µg/m³, the median of 4 live PurpleAir sensors. Open the windows. Great for outdoor activity.
Why is there smoke in Bellevue today?
Almost always something burning a long way off. From roughly July into October it is wildfire smoke — Cascade fires like Bolt Creek and Loch Katrine in 2022, Oregon fires as in September 2020, or British Columbia fires carried south on a northeasterly wind. In the colder months, smoke on a still night is usually residential wood burning held down by an inversion. Wind direction is the quickest tell: a northeasterly in summer generally means Canadian smoke, while a returning marine flow off Puget Sound is what clears it out.
Is Bellevue's air better than Seattle's?
Not reliably. Both sit in the same Puget Sound lowland airshed, and during the October 2022 smoke event local coverage noted that some of the worst readings were on the Eastside. Bellevue has no large local pollution source of its own, but on smoke days the difference between Bellevue and Seattle is usually smaller than the difference between one Bellevue neighborhood and another on a given hour.
Does Canadian wildfire smoke reach Bellevue?
It does, and how badly depends on the wind. In July 2026 northeasterly winds pushed Canadian wildfire smoke into western Washington during a heat advisory. Whatcom and Skagit counties went under an air quality alert with unhealthy levels forecast near Bellingham and Mount Vernon, while the Seattle and Bellevue area stayed at Moderate and was not placed under an alert at all. That is the usual pattern — the northern border counties take the brunt — but not every time.
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 Bellevue, 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 Bellevue
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